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The experimental measurement of density and enthalpy of mixture for two binary liquid mixtures of n-tridecane or n-tetradecane with decalin was reported in this paper. The measurements were conducted at a temperature range of 293.15–323.15 K and at 303.15 K using calorimeter C80. The mixtures were analyzed at various proportions, including the entire composition range and dilute solutions. The excess molar volume (VE) and excess molar enthalpy (HE) of mixtures were calculated and fitted using the Redlich–Kister equation. The paper observed the expansion phenomenon for the VE at all temperatures, including over the entire composition range and dilute solutions. Additionally, the HE exhibited endothermic behavior at the studied temperature range and composition range. The Prigogine–Flory–Patterson (PFP) theory was utilized to predict both thermodynamic properties, namely the VE and HE. The results obtained using the PFP theory were compared with those obtained using the Treszczanowicz and Benson association (TB) model for VE and with the NRTL, Wilson, and Flory models for HE. The PFP model, which employed a single-fitted parameter to describe VE, demonstrated satisfactory performance in predicting VE. Conversely, the Treszczanowicz and Benson association (TB) model yielded relatively poor results in fitting VE. However, the NRTL, Wilson, PFP, and Flory models exhibited good performance in predicting HE. [ABSTRACT FROM AUTHOR]

The dysregulation in heat balance, the main cause of exertional heat stroke, occurs not only in midsummer but also in the cold season. Possible causes of this are a reduction in convection and evaporation due to tailwinds and an acceleration of radiant heat inflow. Although the amount of radiant heat that reaches the surface can be estimated, the actual amount of heat that flows into the body cannot be specified yet. This paper made an experimental attempt at this. A device is made up of a temperature controllable heat sink and heat flow detector, which keeps the surface temperature constant and has a heat exchange coefficient comparable to that of the human body surface. The output of this device (total heat exchange) was divided into radiant heat exchange and other heat exchange using a standard radiant heat calibrator, Leslie cube. A phenomenon, in which a wet surface while the surface temperature was low absorbed larger heat than that of the dry surface, was found. And authors named this "hidden heat inflow". As a result of multiple regression analyses, both radiant heat exchange and other heat exchanges are closely related to the surface temperature, and the maximum difference in total heat exchange during the experiment reached 200 kcal/m2/h. It has been suggested that this phenomenon may also occur on the surface of human skin. One of the causes of this "hidden heat inflow" is considered to be the decrease in evaporative cooling due to the decrease in surface temperature. However, this alone cannot explain all of the phenomena, so water vapor aggregation may also be involved. A "hidden heat inflow" as a sufficient heat source for exertional heat stroke or collapse during a marathon race on a cold day was evidenced experimentally. [ABSTRACT FROM AUTHOR]

This paper employs the inclusion-based boundary element method (iBEM) to delve into heat transfer phenomena in composites. Initially, we integrate the heat flow function and ellipsoidal integral into a bounded domain containing multiple ellipsoidal inhomogeneities. The eigen-temperature gradient is utilized to simulate the thermal mismatch between inhomogeneities and the matrix. Subsequently, the temperature field is computed considering boundary heat flux and temperature conditions, eigen-temperature gradient, and virtual heat source acting on inhomogeneities. The eigen-temperature gradient and virtual heat source are then solved using the equivalent heat flow conditions to obtain the steady-state heat conduction results within the bounded domain. Through comprehensive numerical examples, we analyze the temperature distribution within composite and scrutinize the impact of particle shapes, orientations, volume fractions, and thermal conductivity ratios on the effective thermal conductivity of composite. Furthermore, we explore the distinctive properties of functional gradient material. Additionally, a comparison between iBEM and the finite element method is conducted. The findings reveal a progressive enhancement in the thermal conductivity of composite as the particle shape transitions from spherical to fibrous. [ABSTRACT FROM AUTHOR]

Fiber-reinforced polymer and metal-laminated structures are widely used in aerospace and military fields because of their excellent mechanical and physical properties. However, the materials are prone to processing defects such as burring and furry during processing. According to the mechanism of vibration cutting, the mixed-frequency vibration tool holder (MFVT) with low frequency and ultrasonic-combined vibration is designed and manufactured in this paper. The low-frequency vibration module (LFVM) and the ultrasonic vibration module (UVM) of the tool holder are designed theoretically and studied experimentally. The working performance and stability of the MFVT are tested and analyzed. The results show that the combination of ultrasonic vibration and low-frequency vibration of the tool holder can meet the requirements of design and tool holder. Among them, the exciting surface has the greatest influence on the motion curve of the LFVM. The amplitude of low-frequency vibration decreases with the increase of tool holder speed. When the UVM is running continuously, the temperature rise tends to be balanced. The amplitude and resonant frequency of ultrasonic vibration will decrease with the increase of operating temperature. The heat generated at the end of the cutter chuck accounts for the total heat generated by the horn 98.7% of the amount, the stable temperature reached 231℃. [ABSTRACT FROM AUTHOR]

This paper introduces a novel hybrid material, MoS2@Ag@PA, with a core–shell structure aimed at improving the fire safety and critical properties of ethylene vinyl acetate (EVA). The incorporation of 2% of this hybrid material results in a remarkable enhancement in both thermal conductivity and tensile strength of EVA composites, increasing by 52.4% and 22.6%, respectively. Furthermore, the inclusion of 2% of this material leads to a significant reduction in the peak of heat release rate, total heat release, and total smoke production of the EVA composites by 36.2%, 28.1%, and 29.7%, respectively, compared to pure EVA. This indicates a substantial improvement in fire safety, mechanical properties, and thermal conductivity of the EVA composites. The enhanced flame retardancy of the EVA composites is primarily attributed to the synergistic effect of various substances within the hybrid material. Therefore, the design of these hybrids presents a promising approach to enhance the overall performance of EVA. [ABSTRACT FROM AUTHOR]

This is a global ocean climatological dataset of 17 thermohaline parameters such as isothermal layer (ITL) depth (hT), mixed layer (ML) depth (hD), thermocline gradient (GT), pycnocline gradient (GD) determined from temperature (T) and salinity (S) profiles of the National Centers for Environmental Information (NCEI) world ocean atlas 2018 (WOA18) using the double gradient method along with the identity-index (i-index) showing the quality of the determination. With the identified (hT, hD) and (GT, GD), other parameters such as ITL heat content (HITL), mixed layer fresh-water content (FML), maximum thermocline gradient (GTmax), thermocline depth (hth), temperature at thermocline depth (Tth), maximum density gradient GDmax), pycnocline depth (hpyc), density at pycnocline depth (ρpyc), and (hT − hD) (barrier layer if positive or compensated layer if negative). The dataset is located at the NOAA/NCEI website (https://doi.org/10.25921/j3v2-jy50). It provides useful background information for ocean mixed layer dynamics, air-sea interaction, climatological studies. This paper is the only document for the dataset. [ABSTRACT FROM AUTHOR]

AA6101 Al alloy is widely used as a high-strength conductive aluminum alloy, and the contents and existence of Mg and Si can influence its electrical conductivity and mechanical properties obviously. In this paper, experiments were conducted to find the optimal Mg, Si additions and Mg/Si ratio and then combined with heat treatment to improve the EC and mechanical properties at the same time. Firstly, considering the proper Mg/Si ratio, two optimal Mg and Si additions were determined: Al–0.7Mg–0.5Si and Al–0.4Mg–0.7Si with EC of 51.5%IACS and 51.4%IACS, and through homogenization treatment, their EC improved to 57.0%IACS and 55.7%IACS, respectively. Then, appropriate Fe was added to further control Si to achieve the balance of EC and mechanical properties. Results showed that for AA6101 Al alloy the ideal Mg/Si mass ratio was 1.4 and high Mg and low Si can obtain good EC and mechanical properties. Besides, it can be found that at low Mg/Si ratio, the alloy conductivity takes longer to reach its peak hardness. So the best performance Al–0.7Mg–0.5Si–0.2Fe alloy was obtained within the range of AA6101 national standard. The EC of Al–0.7Mg–0.5Si–0.2Fe can reach 56.3%IACS, and hardness is 91.3 Hv. Based on the study, a schematic diagram was drawn to analyze the influence mechanisms of Mg, Si and Fe on EC and hardness of AA6101 Al alloy. [ABSTRACT FROM AUTHOR]

This paper shows a novel approach and a new model to find the relation of formulas between the thermodynamic parameters and electromagnetic parameters, directly and indirectly. Effectiveness of formulas is discussed by considering issues: no thermoregulation process (including body metabolism), no heat transfer consideration, and the Heating loss has not occurred and boundary conditions in a closed system. The enthalpy, internal energy, and Gibbs free energy are perfect indicators for describing bio-reaction in the human body. Because they are state functions (they are independent of intermediate steps, just first and final steps), they are affected by the SAR estimation that represents the absorption power throughout human tissue. These formulas brought in many features to control body reactions or Krebs cycle. Moreover, the derived formulas convert the reaction from non-spontaneous to spontaneous form by converting Gibbs free energy to a negative value. According to findings, the model can be applied in across many disciplines, such as medical treatment, lipid decomposition, cancer healing, and physical therapy. And in the end, as a result of an increase in the concentration of electromagnetic waves in the atmosphere due to technological development, which urges urgently to amend and update all equations to take into account the effect of magnetic waves in all disciplines affected by them. [ABSTRACT FROM AUTHOR]

During the pulsed laser cladding process, complex thermal accumulation occurs between powder and beam due to the pulsed laser periodic change. The selection of process parameters affects the cladding layer quality, and the correlation between the parameters is high. It is of great significance to obtain high quality cladding layer to determine the influence of the powder-carrying gas nitrogen velocity, powder feeding port diameter, and powder feeding angle on the powder flow, as well as the optimal powder shading rate and the mechanism of powder interaction with pulsed laser beam. In this paper, a gas–solid coupling model during the pulsed laser cladding process of three-beam coaxial powder feeder was established, and the rotating Gaussian heat source function of pulsed laser was written to calculate the temperature, flow velocity, and concentration distribution considering the interaction between laser and powder. The orthogonal test method was used to optimize the process parameters in order to reduce the shading rate of powder and improve the laser energy utilization. On this basis, a full cycle three-dimensional multi-field coupling numerical model for pulsed laser cladding process was established, and the temperature, flow, stress fields, and multi-component heat and mass transfer behaviors were calculated under different powder shading rates. The flow temperature of powder was collected by infrared thermometer and compared with the numerical results, the reliability of the model was verified. This study provides a significant theoretical basis for the full-cycle optimization of process parameters and the improvement of cladding layer quality during pulsed laser cladding. [ABSTRACT FROM AUTHOR]

Context: The reactions of radicals with O2 play the important role in the biological, medicinal, and industrial processes. The mechanism of this reaction is studied previously for the alkane, alkene, alkyne, phenols, and close-related radicals. According to these studies, the formation of intermediates in these reactions is predicted only for the aromatic radicals. Thus, the Van der Waals complexes of O2 with phenyl or benzyl radicals are predicted, as well as the π-π cluster for benzene. However, the possibility of the formation of such intermediate π-π clusters in the case of bisphenol radicals and the thermochemistry of its formation is not studied. Bisphenols are one of the main components of bio-oil, produced during pyrolysis of lignin-contained biomass. Synthetic bisphenols are used in polycarbonate plastics, epoxy resins, and thermal papers. Their mechanism of oxidation is important for the determination of fire safety of these materials, the possibility of using them as additives for fuels for the decreasing and the description of the ignition delays, as well as for the determination of its health risk assessment in medicine. Methods: The five DFT (M06-2X (i = 1), B3LYP (i = 2), wB97XD (i = 3), M08HX (i = 4), MN15 (i = 5)) approaches with 6–311 + + G(d,p) basis set are used for the determination of standard enthalpies of atomization (ΔraHo(Yi)) of considered compounds (molecules, radicals, and transition states). These values of ΔraHo(Yi) are corrected using the empirical linear calibration dependencies, reported previously. The different calibration dependencies are used for the hydrocarbons (including the aromatics and simple oxygenated derivatives) and for the peroxides. The corrected values of ΔraHo(Yi, CORR) are used according to Hess’s law for the determination of ΔfHo(Yi, CORR). The most consistent values of ΔfHo(Y, MEAN) are derived from the coordination of the values of ΔfHo(Yi, CORR) using the intersection of their values of standard deviations (3SDi). These values of ΔfHo(Y, MEAN), as well as the B3LYP values of So(Y), which are accounting the frequency correction and internal rotations, as well as their temperature dependencies, are used for the determination of thermochemistry of considered reactions and of the calculation, within transition state theory (TST), of the values of high-pressure limits of the rate constant. The values of Ho(Yi), So(Yi), and Go(Yi) are calculated using the Gaussian 16w program. The temperature dependencies of thermochemical properties and the values of rate constants are determined using the ChemRate program (v.1.5). The optimized structures are visualized using the Chemcraft. [ABSTRACT FROM AUTHOR]

Legendre transformation is a highly important topic in the study of thermodynamics. In this paper, the idea of Legendre transformation is discussed in a simple manner, and the interconnections between thermodynamic potentials are shown using Legendre transformation. Not only common potentials—internal energy, Helmholtz free energy, Gibbs potential, and enthalpy—a few uncommon potentials of various thermodynamic systems are also discussed. [ABSTRACT FROM AUTHOR]

This three-part paper lends new insight into the interpretation of internal state variable (ISV) theory and fundamentals of the behavior of thermally activated dislocation ensembles. We formally define important physical concepts undergirding ISV theory such as configurational subsystems (e.g., individual grains or phases), constrained local equilibrium, and thermally activated dislocation reactions in the context of crystal plasticity and then implement these concepts within a nonequilibrium statistical thermodynamics framework. The primal importance of the Gibbs free energy barrier to dislocation reactions within each subsystem is emphasized since the enthalpy barriers are affected by local constraint and resulting long-range and short-range athermal internal stresses acting within subsystems. Kinetic and kinematic aspects of individual dislocation reactions are defined. The role of athermal internal stresses in stabilizing the positions of dislocations between barriers is acknowledged by the formal identification of the anelastic deformation, along with its role in contributing to thermal dissipation. Thermal and configurational intrinsic entropy change that contribute to the change of Gibbs free energy as a driving force for reactions are formally introduced in the same way as in first principles methods and are based on probability of pending dislocation reactions at each step. We distinguish equilibrium thermodynamics up to the saddle point of reactions, for which change of both configurational and thermal entropy applies, from post-saddle point extended glide of dislocations, which couples with the thermal bath via dispersive phonon dynamics. We write subsystem and ensemble relations for intrinsic entropy production. The concept of "degree-of-correlation" of the enthalpy barriers of thermally activated dislocation processes is introduced at both the subsystem level and across the overall ensemble of subsystems, based on the ratio of the weighted average enthalpy barrier to the maximum (rate-limiting) enthalpy barrier. It is argued that nonequilibrium trajectories progressively move toward correlated behavior of the ensemble by virtue of internal stress redistribution among interacting subsystems that are favorable and unfavorable to reactions. The degree-of-correlation is a many-body concept involving populations of dislocations within and among various configurational subsystems. [ABSTRACT FROM AUTHOR]

This paper describes a procedure to precisely decouple the electrostatic and the nonelectrostatic contributions to the water activity of an electrolyte solution, using the partial molal enthalpy of water in the electrolyte solution. This work is an extension of our previous work [Sahu et al. in Fluid Phase Equil. 460:57–68, 2018, Data in Brief 19:485–494, 2018], where a methodology to segregate the electrostatic and non-electrostatic contributions to the water activity was discussed and the constancy of the electrostatic contribution to the water activity was shown. However, in this paper, it is a noticeable point that even a 2% variation in the electrostatic contribution to the water activity leads to a very large deviation in the electrostatic contributions to the partial molal enthalpy of water. Therefore, due to the high sensitivity of the enthalpy to the variation of the water activity, the partial molal enthalpy of water is used for refinement of the method of partitioning the water activity into electrostatic and nonelectrostatic contributions and to provide the physical interpretation of the electrostatic and nonelectrostatic contribution to the partial molal enthalpy of water. This paper also describes the procedure to estimate the partial molal enthalpy of water from the water activity of the electrolyte solution. Microcalorimetr has been used to estimate the closed spaced points of partial molal enthalpies. [ABSTRACT FROM AUTHOR]

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A van der Waals (vdW) heterostructure, can be used in efficient heat management, due to its promising anisotropic thermal transport feature, with high heat conductance in one direction and low conductance in the rest. A carbon nanotube (CNT) bundle, can be used as one of the most feasible vdW heterostructures in a wide range of nanoscale devices. However, detailed investigations of heat transport in CNT bundles are still lacking. In this paper, we study heat transport in different CNT bundles—homogeneous bundles consisting of the one CNT radius (curvature) and inhomogeneous bundles constructed from different CNTs with different curvatures. We also investigate the comparison between two possible thermostatting configurations: the two ends connected (TEC) case in which there is at least a direct covalently connected path between the hot and cold heat baths, and the one end connected (OEC) case in which the system can be divided at least into two parts, by a vdW interacting interface. Nonequilibrium molecular dynamics simulations have been carried out for a wide range of configurations and curvature differences. We find that, in homogeneous bundles, by increasing the number of outer CNTs, the heat conductance increases. In inhomogeneous bundles, the total heat flux shows dependence on the difference between the curvature of the core and outer CNTs. The less the difference between the curvature of the core and the outer CNTs, the more the thermal conductance in the system. By investigating the spectral heat conductance (SHC) in the system, we found that a larger curvature difference between the core and outer CNTs leads to a considerable decrease in the contribution of 0–10 THz phonons in the bundled zone. These results provide an insightful understanding of the heat transport mechanism in vdW nano-heterostructures, more important for designing nanoelectronic devices as well as systems in which asymmetry plays a significant role. [ABSTRACT FROM AUTHOR]

The stabilities, mechanical and electronic properties and Debye temperature of three novel Cr2C structures (Pnnm, Amm2 and P-31m space groups) are investigated and discussed in this paper. All of them are thermodynamically, mechanically and dynamically stable. Notably, the hardness of Amm2 Cr2C is 26.30 GPa at ambient pressure, better than the known Cr2C structures. Based on the results of the density of state and Mulliken overlap population simulation, there is strong covalent-ionic Cr-C bonding interaction in Amm2 Cr2C, which is also revealed by the analysis of Debye temperature. Furthermore, the relative enthalpy as functional of pressure of all structures were calculated to understand their stabilities under high pressure. Overall, the predicted stable structures will provide more options to facility the synthesis and application of transition metal carbides. [ABSTRACT FROM AUTHOR]

Aristino-Traianoupolis area hosts one of the most significant water-dominated low-temperature geothermal fields in Greece. It is located on the southwestern uplifted margin of the Tertiary Evros Delta molassic basin, 10 km east of the town of Alexandroupolis (Thrace, NE Greece). The upper hydrothermal system of the Aristino Geothermal Field (AGF), one of the most promising in continental Greece, contains fluids with temperatures ranging from 51 to 99 °C, within a series of overlapping aquifers at very low depths (100–430 m). The main geothermal anomaly for temperatures higher than 90 °C covers an area of 6 km2, to a maximum prospected depth of 500 m below ground surface. The scattered regional anomaly exceeds 50 km2 and is characterized by excessively high and abruptly changing thermal gradient (42 to 450 °C/km) and heat flow (80–800 mW/m2), that are both typical of a fault-controlled hydrothermal system. Since 1993, the AGF has undergone non-systematic geothermal investigation, with emphasis on low-depth (100–500 m) drilling. This paper provides, for the first time, a synthetic and detailed evaluation of all available temperature data gathered in the last 25 years. The steady-state temperature logs reveal the dominant role of conduction for the upper geothermal system, accompanied, in most cases, by rapidly changing and abnormally high thermal gradients (100–450 °C/km), triggered, most probably, by a deeper system of higher temperature. This hypothesis is also supported by the applied chemical geothermometers, which suggest initial fluid temperatures at 140–150 °C, the hydrochemical characteristics of the fluids hosted in the deeper and most promising investigated reservoir (ignimbrite) of the upper system, and the extrapolated temperatures from the conductive temperature–depth profiles. The lower widespread medium enthalpy hydrothermal system should extend at depths 500–1000 m within volcanics and the expected Eocene limestones and basal clastic series of the Tertiary sequence that have filled the basin. Nevertheless, these assumptions need to be verified by appropriate investigations and new drillings at depths greater than 600–700 m, which would confirm the presence of a productive medium enthalpy reservoir. [ABSTRACT FROM AUTHOR]

Extreme heat has occurred more frequently in recent years and will intensify in the future, and this change has serious impacts on rice (Oryza sativa L.) yields. Thus, it was crucial to evaluate its influence on rice yield reductions. Recent papers have shown that a lack of experimental data makes it difficult for most crop models to capture the impacts of heat stress. Therefore, this paper explored how to improve the performance of crop models under extreme heat stress based on the Decision Support System for Agrotechnology Transfer (DSSAT) CERES-Rice model. This study primarily focused on (i) quantifying spikelet fertility based on daily temperature and durations derived from controlled experiments, (ii) improving the performance of the CERES-Rice model under extreme heat stress, and (iii) simulating historical and future rice yields using the improved model. Specifically, a meta-analysis method was utilized to build a new heat stress function between spikelet fertility and temperature and heat day duration with high realization. Subsequently, independent artificial controlled experiments at two sites were proposed to calibrate and validate the CERES-Rice model. The results showed a higher R2 (> 0.739) and a lower RMSE that was reduced by 38~68% after incorporating the new heat stress function in the CERES-Rice model compared with that of the original model. Furthermore, a historical simulation (1980–2010) demonstrated that an improved CERES-Rice model could better capture rice yield in response to extreme heat. Using an ensemble of five climate model datasets and four Representative Concentration Pathways (RCPs), the analysis of the projected future (2020–2099) rice yield showed that the rice yield reduction caused by high temperature was considerable; however, the rice yields were overestimated by 34% and 18%, respectively, at the two sites. Some regions rarely affected by heat are likely to experience yield reductions in the future due to climate change. [ABSTRACT FROM AUTHOR]

This paper proposes a heat source model for dissimilar Al/Cu friction stir welding (FSW). First, tool torques of various welding parameters are real-time monitored and then analyzed for plunging, dwelling, welding and cooling stages of the FSW process. Second, total heat input is obtained based on the measured tool torque and is utilized to establish a combined heat source model of the four stages during Al/Cu FSW. In the model, heat distribution on the shoulder and the pin is regarded as planar and volumetric heat flux, respectively. Finally, the temperature distribution and evolution in dissimilar Al/Cu FSW are calculated by developing a numerical model, and the results are found to be in good agreement with the experimental observations. The present work avoids the complexity of determining different contact variables at the tool-workpiece interface and also provides an effective method for a quick prediction of the thermal responses during the full process of dissimilar materials FSW. [ABSTRACT FROM AUTHOR]

Herein, we systematically studied the thermodynamic and kinetic aspects of glass forming compositions in Ca–Mg–Cu alloy obtained by drawing the isocontour. Parameter derived from the enthalpy of chemical mixing (ΔHchem) and normalized mismatch entropy () is used as a glass-forming ability (GFA) parameter. Variation of with reported and calculated compositions is evaluated. Linear relation of Cu with is observed, whereas inverse relation of Ca and Mg is obtained. The linear variation of with a supercooled liquid region (SCLR) () is studied. Inverse correlation of critical cooling rate () with is obtained. for predicted compositions is found close to that of reported compositions. Therefore, Cu should be added carefully with other elements to improve the GFA and reduce the cooling rate of Ca‒Mg‒Cu glassy. In this paper, an empirical correlation of with is proposed, and the modeled values are found to agree with the experimental values. [ABSTRACT FROM AUTHOR]

The multi-pass double-sided arc welding (DSAW), as an advanced connection method, is typical for T-joints in large-scale arc structures. However, due to unknown deformation on reserved-clearance in the welding process, non-penetration is likely to occur. Therefore, it is of great significance to carry out welding deformation prediction and reserved-clearance calculation. In this paper, a dynamic heat distribution model and TEP-FE approach is presented to calculate the welding deformation on reserved-clearance. Furthermore, a deformation pattern is suggested to predict the clearance change. Firstly, a dynamic heat distribution and moving heat approach is proposed to calculate the temperature field of the DSAW process. Afterwards, the thermal elastic–plastic (TEP) finite element (FE) analysis is applied to calculate the welding deformation in the DSAW process. The heat distribution and moving heat function is iterated to the TEP-FE analysis as a subroutine. Heat convection and radiation dissipation are taken into consideration in the DSAW process. Compared with the previous welding calculation methods, the new method focuses on real-time deformation on reserved-clearance and arc-track moving heat source. Finally, the calculated results in TEP-FE analysis are verified by the measurement results. The welding deformation on reserved-clearance is in good agreement with the experimental results. The error of maximum reserved-clearance deformation between calculation and experimental is 7.8%. [ABSTRACT FROM AUTHOR]

Powders of various metals and boron are widely used in composite solid propellants to increase the combustion temperature and specific impulse of rocket engines. This paper presents the results of an experimental study of oxidation and ignition of ultrafine Alex aluminum powder, amorphous boron, microsized Al aluminum powder, and AlB2 and AlB12 aluminum borides in air. Metal and boron powders are heated and ignited by a CO2 laser in a heat flux density range of 65–190 W/cm2. It is revealed on the basis of thermal analysis data that the powder reactivity parameters are arranged in the following sequence (in descending order of activity): Alex B AlB12 AlB2 Al. The total specific heat release and the mass variation rate reach maximum values during the oxidation of amorphous boron and AlB12 aluminum dodecaboride. The Alex, boron, and AlB12 powders are easier to ignite in air under the action of an external radiant source. The power exponent in a dependence between the ignition delay time and the heat flux density = for the Al, AlB2, and AlB12 powders are approximately the same and equal to 2.0, and it is lower and reaches = 1.5 and 1.0 for ultrafine Alex and boron powders, respectively. [ABSTRACT FROM AUTHOR]

Spindles in precision boring machine often work in low speed and heavy load without internal cooling, and the thermal error is non-negligible. An external cooling system was proposed, and the effectiveness of the proposed scheme needs to be preliminarily verified by simulation before building the cooling system. Thermal simulations of the spindle with an external cooler require calculating the thermal resistance of the thermal grease-coated interface between the cooler and spindle. Models describing the contact thermal resistance and total thermal resistance for metal contact filled with silicone grease based on solid–liquid interface force equivalence were described in this paper, and experiments were also conducted to verify the accuracy of these models. The contact thermal resistances between the cast iron/copper and silicone grease on flat or cambered surfaces were calculated, and the bulk thermal resistance of the silicone grease layer was calculated. The total heat transferred between the cooler and the silicone grease-coated interface of the spindle was calculated. Heat transfer and heat generation in the spindle were calculated, and a finite element model was established to verify the effectiveness of the designed external cooling scheme. Finally, the proposed cooling scheme is developed, and quantitative analysis for experiments show that the constant temperature cooling (20 °C, 18 °C, and 16 °C) significantly improved the thermal error stability, hence decreases the time of reaching thermal equilibrium by 42.95%, 39.57%, and 39.84% under a rotation speed of 1500 rpm, and 23.94%, 51.21%, and 42.07% under a rotation speed 3000 rpm. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the contribution of the mixing enthalpy to the stability of the faced-centered cubic (fcc) phase of the Co–Cr–Fe–Mn–Ni system. For this purpose, systematic first principles calculations on Special Quasirandom Structures (SQS) were performed in a comprehensive manner on the fcc solution in every 5 2 = 10 binary, 5 3 = 10 ternary, 5 4 = 5 quaternary and the quinary systems. The magnetic contributions have been considered carefully i.e. including non-collinear spin polarization. An analysis of the different system order interactions to the enthalpy of mixing is detailed. This concludes that, at equiatomic composition, there is no special "cocktail" effect with an increase of components and that the thermodynamic properties can be well anticipated from the lower order systems, essentially binary and ternary systems. [ABSTRACT FROM AUTHOR]

This paper presents the use of a nanosecond pulse laser for masking the AISI316L stainless steel surface prior to the electrochemical machining process. The laser-masked surface was prepared with an attempt to grow a chromium oxide layer as a passive mask for the selective electrochemical machining process. The effects of laser power, traverse speed, and scan overlap on the roughness, surface height, and chemical composition of laser-masked region were investigated in this study. The influence of electric current and electrochemical etching time on the machined surface morphology was also examined in the experiment. The results showed that using the laser power of 3–4 W associated with the laser traverse speed of 30–50 mm/s can provide the oxide mask with low roughness on the stainless steel surface. The electrochemical machining rate of laser-masked surface was only 0.16 μm/s, while the removal rate of unmasked surface was 0.36 μm/s. Although there was no significant difference between the scan overlaps on the obtained surface roughness, the 0% overlap was suggested to keep the surface masking time and total heat input toward the workpiece at minimum. [ABSTRACT FROM AUTHOR]

The observed heat flux from the Earth is created mainly by the heat released due to radioactive decay, secular cooling of the Earth, and solidification of the growing inner core. The structure of convective flows and, accordingly, the geodynamic manifestations of convection depend on the proportion in which the mantle is heated from below by the flux from the core and from the inside by internal heat sources. For a long time, the heat flux from the core was estimated under the assumption that almost all of it is carried to the surface by plumes in hot spots. However, this leads to an imbalance and a deficit in the total heat of the Earth. In this paper, the sources of the Earth's heat are analyzed and a heat balance consistent with the available set of observational data is presented. The distribution of the heat flux density at the boundary with the core and on the surface is calculated, and it is shown that plumes carry to the surface only a part of the heat coming from the core even in the simplest convection model with constant viscosity. [ABSTRACT FROM AUTHOR]

Systematic investigation of structural, electronic, optical, mechanical, and adsorption properties of group-IV cubical transition metal nitrides MN (M = Ti, Zr and Hf) is presented in this paper. The structural characteristics, projected densities of states (PDOS), mechanical strength, optical, and adsorption properties have been calculated using first-principles based on density functional theory (DFT). The findings of the comparative and theoretical study showed that, amongst MN, HfN has comparatively higher optical conductivity. Its higher absorption coefficient and least reflectivity ensure the availability of adequate light on its surface. HfN is also found to be more thermally stable with cohesive energy of − 19.112 eV/atom and formation enthalpy of − 5.169 eV/atom. Further, the higher bulk modulus (286 GPa), Young's modulus (600 GPa), and shear modulus (261 GPa) also ensured its remarkable mechanical strength. Apart from this, the calculated lower adsorption energy (2.3 eV) of H2O molecule over the surface of HfN showed an improved performance in the corrosive environment. The results give a clear indication that HfN may prove as an effective alternative candidate to be utilized in many modern bioelectronics applications. [ABSTRACT FROM AUTHOR]

Enthalpy-entropy compensation supposes that differences in activation enthalpy ∆ H for different reactions (or, typically in biochemistry, the same reaction catalysed by enzymes obtained from different species) may be compensated for by differences in activation entropy ∆ S . At the isokinetic temperature the compensation is exact, so that all samples have the same activity. These ideas have been controversial for several decades, but examples are still frequently reported as evidence of a real phenomenon, nearly all of the reports ignoring or discounting the possibility of a statistical artefact. Even for measurements in pure chemistry artefacts occur often, and they are almost inescapable in enzyme kinetics and other fields that involve biological macromolecules, on account of limited stability and the fact that kinetic equations are normally valid only over a restricted range of temperature. Here I review the current status and correct an error in a recent book chapter. [ABSTRACT FROM AUTHOR]

This paper assesses the heat transfer performance of nanofluids containing a core–shell structure of SiO2 –TiO2 nanoparticles of low concentration in a mixture of water and ethylene glycol (EG) in a commercially available heat exchanger. For heat transfer analysis, 0–0.025% of SiO2 –TiO2 nanoparticles were employed in a finned-tube cross-flow heat exchanger (automobile radiator kit). The obtained results indicate that SiO2 –TiO2 particles have an amorphous structure and make it possible to increase the thermal conductivity as the nanoparticle fraction increases up to 0.04%. The nanofluid characteristics (Reynolds, Nusselt, and Prandtl numbers) increase, leading to an increase in the convection coefficient. As the thermal conductivity and the convection coefficient increase, the total heat transfer improves. Finally, the heat transfer effectiveness increases linearly by 21% with 0.025% mass fraction of SiO2 –TiO2 in a water/EG-based fluid. [ABSTRACT FROM AUTHOR]

Rapid combustion of fossil fuels in huge quantities resulted in the enormous release of CO2 in the atmosphere. Subsequently, leading to the greenhouse gas effect and climate change and contemporarily, quest and usage of fossil fuels has increased dramatically in recent times. The only solution to resolve the problem of CO2 emissions to the atmosphere is geological/subsurface storage of carbon dioxide or carbon capture and storage (CCS). Additionally, CO2 can be employed in the oil and gas fields for enhanced oil recovery operations and this cyclic form of the carbon dioxide injection into reservoirs for recovering oil and gas is known as CO2 Enhanced Oil and Gas Recovery (EOGR). Hence, this paper presents the CO2 retention dominance in tight oil and gas reservoirs in the Western Canadian Sedimentary Basin (WCSB) of the Alberta Province, Canada. Actually, hysteresis modeling was applied in the oil and gas reservoirs of WCSB for sequestering or trapping CO2 and EOR as well. Totally, four cases were taken for the investigation, such as WCSB Alberta tight oil and gas reservoirs with CO2 huff-n-puff and flooding processes. Actually, Canada has complex geology and therefore, implicate that it can serve as a promising candidate that is suitable and safer place for CO2 storage. Furthermore, injection pressure, time, rate (mass), number of cycles, soaking time, fracture half-length, conductivity, porosity, permeability, and initial reservoir pressure were taken as input parameters and cumulative oil production and oil recovery factor are the output parameters, this is mainly for tight oil reservoirs. In the tight gas reservoirs, only the output parameters differ from the oil reservoir, such as cumulative gas production and gas recovery factor. Reservoirs were modelled to operate for 30 years of oil and gas production and the factor year was designated as decision-making unit (DMU). CO2 retention was estimated in all four models and overall the gas retention in four cases showed a near sinusoidal behavior and the variations are sporadic. More than 80% CO2 retention in these tight formations were achieved and the major influencing factors that govern the CO2 storage in these tight reservoirs are injection pressure, time, mass, number of cycles, and soaking time. In general, the subsurface geology of the Canada is very complex consisting with many structural and stratigraphic layers and thus, it offers safe location for CO2 storage through retention mechanism and increasing the efficiency and reliability of oil and gas extraction from these complicated subsurface formations. [ABSTRACT FROM AUTHOR]

In our previous papers, a new geometric model has been proposed for calculating the thermodynamic properties of a multi-component system in terms of the properties of its three sub-binary systems. This new model can overcome the inherent defects of the traditional symmetrical and asymmetrical geometric models. Consequently, it is more reasonable theoretically and more reliable in practical applications. However, calculations using this new model involve a series of integration processes which make it complicated and affects its applications. Since a large number of real systems can be approximately fit through a Redlich-Kister polynomial, in this paper a new formalism is presented for the model, based on the binary Redlich-Kister type parameters. The advantage of this treatment is that the whole integration process is avoided by using algebraic operations, thereby simplifying the calculation. [ABSTRACT FROM AUTHOR]

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In this paper, a method combining ultrasonic travel time measurement with inversion is proposed to reconstruct the solid temperature field. Based on the measured transient ultrasonic propagation time, the inverse problem of acoustic thermal coupling is solved directly, and the unknown equivalent heat flow is estimated. Then, the time and space distribution of the internal temperature field can be reconstructed accurately by calculating the corresponding heat conduction problems. Through the estimation of two typical heat flow function forms, the accuracy and influencing factors are simulated and analyzed. The feasibility and error of this method are analyzed through a transient verification experiment of a steel plate heated first and then cooled and a steady-state experiment in the literature. The results show that, compared with the previous methods, this method can predict the distribution of non-uniform temperature field more accurately and effectively. This method is expected to be an effective method for nondestructive testing of temperature distribution of solid structures. [ABSTRACT FROM AUTHOR]

The classical Green's functions used in the literature for a heat source in a homogeneous elastic medium cannot lead to finite remote thermal stresses in the medium, so that they may not work well in practical thermal stress analyses. In this paper, we develop a practical Green's function for a heat source disposed eccentrically into an elastic disk/cylinder subject to plane deformation. The edge of the disk/cylinder is assumed to be thermally permeable and traction-free. The full thermal stress field induced by the heat source in the disk/cylinder is determined exactly and explicitly via the Cauchy integral techniques. In particular, a very simple formula is obtained to describe the hoop thermal stress on the edge of the disk/cylinder, which may be conveniently useful for analyzing the thermal stresses in microelectronic components. [ABSTRACT FROM AUTHOR]

The feed system of CNC machine tool has the characteristics of multiple heat sources and strong time-varying heat generation rate of each heat source. However, previous studies have paid little attention to the time-varying heat generation rate of each heat source, so it is difficult to accurately predict the temperature rise and thermal error of the lead screw. In this paper, Monte Carlo (MC) simulation-integrated FEM method was used to capture the heat generation rate of each heat source in the feed system. Consequently, relationship of the ratio of each heat source to the total heat generation rate of the system with the running time was obtained. Then, based on heat ratios of the heat sources, the torque current of the servo motor in the feed system was proposed to calculate the heat generation rate of each heat source. Finally, based on the finite difference method of one-dimensional heat conduction equation, numerical prediction model for thermal error of the lead screw was put forward. Finally, the accuracy and validity of the calculation model were verified by comparing with the experimental results. [ABSTRACT FROM AUTHOR]

Grinding or polishing temperature has an important influence on the life and working performance of parts. The temperature distribution in grinding process is not only related to the total heat generated but also related to the energy partition. In this paper, the polishing force and polishing temperature were measured in the process of polishing aero-engine blades, and the contact arc lengths were calculated indirectly. Thereby, the energy partition was obtained by calculation. It is shown that the correlations between the energy partition and the spindle speed are negative; the correlations between the energy partition and compression depth are also negative; the energy partition increases relative to the increase of feed speed, and the energy partition decreases to a constant pace with the increase of size of abrasive cloth wheel gradually. An energy partition model was fitted, and the model was verified by experiments. [ABSTRACT FROM AUTHOR]

A thorough search of the scientific literature under the auspices of the IUPAC Sub-Committee on Solubility and Equilibrium Data (SSED) has identified and compiled quantitative thermodynamic data for the first sulfate protonation step from about 270 papers, reports, books and electronic databases. A critical evaluation of these sources using well-defined criteria has rejected about half of them. The remaining ('accepted') data reveal that the standard state values of the first protonation constant of the sulfate ion, K 1 o , corresponding to the equilibrium: SO 4 2 - (aq) + H + aq ⇌ HSO 4 - (aq) at infinite dilution, are known to good levels of accuracy up to ~ 250 °C. However, at higher temperatures, and at all temperatures in the presence of added electrolytes, the equilibrium constant values are much less certain. The corresponding values for the enthalpy ( Δ r H 1 o ), entropy ( Δ r S 1 o ) and isobaric heat capacity ( Δ r C p , 1 o ) changes are also moderately well determined at near-ambient temperatures but are much more poorly defined both at higher temperatures and in the presence of even modest concentrations of added electrolytes. Comments on a number of aspects of the data and their evaluation are provided. [ABSTRACT FROM AUTHOR]

Retrograde vaporization effects on oil production are nearly unprecedented to reservoir engineering community, and its relation to formation damage should be explored. For this purpose, this paper elucidates the importance and role of this phenomenon and its phase change heat transfer (PCHT) on fines migration and subsequent, permeability damage in porous rocks bearing oil and gas. Initially, a fine particle energy conversion equation was successfully acquired by combining fine particle mass balance and general energy equations. Moreover, the computational fluid dynamic model (CFD) was adopted for performing numerical modeling. A 2D CFD model using FEA-Comsol 5.0 version was used to simulate the retrograde vaporization of reservoir fluids. Pore walls are designed as non-adiabatic, and therefore, a modified Dittus-Boelter mass transfer model is provided for a fine particle detachment under PCHT. Hence, from the simulation results it was observed that there is a high degree of heat release during reservoir fluid phase change that is from oil to gas for decreasing pressure and increasing saturation time. This heat transfer from the oil and gas influxes contributes in the expulsion and migration of in situ fines in porous media. Also, an increasing rate of enthalpy was achieved that produces a non-isentropic flow, which is required to mobilize the fines in porous medium, and a satisfactory phase transition simulation outputs were obtained and presented as well. Altogether, these factors play a significant role in the fine particle eviction from the pore chamber, thereby plugging in the pore throat and consequently, decreasing the well productivity during transient flow. [ABSTRACT FROM AUTHOR]

Multi-year La Niña events cause prolonged climate disruptions worldwide, but a systematic understanding of the underlying mechanisms is not yet established. Here we show using observations and models from the sixth phase of Coupled Model Intercomparison Project that a greater frequency of consecutive La Niña events is tied to the upper equatorial Pacific Ocean when it favors more rapid heat discharge. The propensity for heat discharge is underscored by negative skewness in upper-ocean heat content, underpinned by southward tropical Pacific wind shift during austral summer. Models with stronger westerly anomalies south of the equator simulate steeper east-to-west upward tilt of the thermocline that is favorable for a greater discharge rate. This highlights the crucial role of the southward wind shift in the nonlinear system of the El Niño-Southern Oscillation. The large inter-model spread in multi-year La Niña processes underscores the need in constraining models for reliable climate prediction and projection. [ABSTRACT FROM AUTHOR]

Marine heatwaves (MHWs) and total heat exposures (THEs), extreme warming events occurring across the global oceans, seriously threaten marine ecosystems and coastal communities as the climate warms. However, future changes in MHWs and THEs in the Arctic Ocean, where unique marine ecosystems are present, are still unclear. Here, based on the latest CMIP6 climate simulations, we find that both MHWs and THEs in the Arctic Ocean are anticipated to intensify in a warming climate, mainly due to Arctic sea ice decline and long-term warming trend, respectively. Particularly striking is the projected rise in MHW mean intensity during the 21st century in the Arctic Ocean, surpassing the global average by more than sevenfold under the CMIP6 SSP585 scenario. This phenomenon, coined the 'Arctic MHW Amplification', underscores an impending and disproportionately elevated threat to the Arctic marine life, necessitating targeted conservation and adaptive strategies. The authors show a marked intensification of marine heatwaves in the Arctic Ocean due to sea ice decline, which is expected to surpass the global mean intensification of marine heatwaves by over sevenfold in future warming climate. [ABSTRACT FROM AUTHOR]

The mixed-valence compound YbB12 displays paradoxical quantum oscillations in electrical resistivity and magnetic torque in a regime with a well-developed insulating charge gap and in the absence of an electronic Fermi surface. However, signatures of such unusual fermionic quasiparticles in other bulk thermodynamic observables have been missing. Here we report the observation of a series of sharp double-peak features in the specific heat as a function of the magnetic field. The measured Hall resistivity evolves smoothly across the field values at which the characteristic anomalies appear in the thermodynamic response and rules out the possibility of conventional electrons as their origin. Our observations of thermodynamic anomalies in a bulk three-dimensional electrical insulator provide the evidence for the presence of emergent dispersing fermionic excitations within the insulating bulk, which sets the stage for further investigation of electron fractionalization in other correlated mixed-valence compounds. Reports of quantum oscillations in the absence of an electronic Fermi surface in Kondo insulator candidates such as SmB6 and YbB12 have been under intense study. Here the authors report the thermodynamic properties of YbB12 in a magnetic field pointing to the presence of in-gap fermionic excitations. [ABSTRACT FROM AUTHOR]

The mismatch between solar radiation resources and building heating demand on a seasonal scale makes cross-seasonal heat storage a crucial technology, especially for plateau areas. Utilizing phase change materials with high energy density and stable heat output effectively improves energy storage efficiency. This study integrates cascaded phase change with a cross-seasonal heat storage system aimed at achieving low-carbon heating. The simulation analyzes heat distribution and temperature changes from the heat storage system to the heating terminal. The results indicate that although the solar collectors operate for 26.3% of the total heat storage and heating period, the cumulative heat stored is 45.4% higher than the total heating load. Heat transferred by the cross-seasonal heat storage system accounts for up to 61.2% of the total heating load. Therefore, the system reduces fuel consumption by 77.6% compared to conventional fossil fuel heating systems. Moreover, radiant floor heating terminals, with a wide range of operating temperatures, match well with cascaded phase change heat storage and can reduce operation time by 19.5% and heat demand by 5.2% compared to conventional radiators. In addition to demonstrating the feasibility of applying cascaded phase change technology in cross-seasonal heat storage heating, this study reveals the lifecycle sustainability due to the shortened heat storage period. The configuration, parameters, and simulation results provide a reference basis for system application and design. [ABSTRACT FROM AUTHOR]

The electricity system and the industrial sector interrelate on the path to decarbonization. The study addresses the drivers and environmental pressure within the industrial sector on the National Electricity System (NES). This article aims to characterize the metabolic pattern of the NES and the industrial sector using the Multiscale Integrated Analysis of Social and Ecological Metabolism (MuSIASEM) from a bioeconomic perspective to identify fields of opportunity in the regulatory policy instruments. A set of extensive and intensive variables (2019) on energy, production factors, and emissions was used at different hierarchical levels based on both subsectors. Our results show that the NES used primary energy sources (PES) and secondary energy carriers to fulfill its functions, of which 72% were domestic sources and 28% were imported. México imported 79.5% of the natural gas (NG) for electricity generation. However, there are favorable conditions for renewable PES to increase the installed capacity of solar plants between 3 and 4 orders of magnitude and 2–3 in wind power from the current capacity. NES's energy consumption per hour of human time is 17,388 MJ/h, with 65% being the heat equivalent to a total energy input consumed of 2139 PJ/y. Public plants contributed 43.7% to the generation, and the independent and self-supply producers the rest. End uses needed the supply of 69.3% of electricity from baseload plants. Sixty-three percent of the metabolic pattern of the industrial sector is based on heat and fuel processes, which depend on NG imports. The NES is reorganizing and recovering its energy autonomy. [ABSTRACT FROM AUTHOR]

An OpenFOAM based turbulence combustion solver with flamelet generated manifolds (FGMs) is presented in this paper. A series of flamelets, representative for turbulent flames, are calculated first by a one-dimensional (1D) detailed chemistry solver with the consideration of both transport and stretch/curvature contributions. The flame structure is then parameterized as a function of multiple reaction control variables. A manifold, which collects the 1D flame properties, is built from the 1D flame solutions. The control variables of the mixture fraction and the progress variable are solved from the corresponding transport equations. During the calculation, the scalar variables, e.g., temperature and species concentration, are retrieved from the manifolds by interpolation. A transport equation for NO is solved to improve its prediction accuracy. To verify the ability to deal with the enthalpy loss effect, the temperature retrieved directly from the manifolds is compared with the temperature solved from a transport equation of absolute enthalpy. The resulting FGM-computational fluid dynamics (CFD) coupled code has three significant features, i.e., accurate NO prediction, the ability to treat the heat loss effect and the adoption at the turbulence level, and high quality prediction within practical industrial configurations. The proposed method is validated against the Sandia flame D, and good agreement with the experimental data is obtained. [ABSTRACT FROM AUTHOR]

Electric hot incremental sheet forming (EHISF) is a technique based on the use of electric current to heat the metal sheet, it consists of a source of direct current (transformer), cables, tool, and plate constituting a closed circuit. According to Joule's law, when the current travels from the tool to the plate, the current density generates heat. It is known that the mechanical and metallurgical proprieties of the materials are highly influenced by the temperature. Then it is important to know how the distribution of heat near the mobile heat source occurs. Recently, some researchers have suggested different techniques for calculating heat distribution as a function of a mobile source. In this paper, it discusses the temperature distributions when the source moves in relation to the conductive medium, comparing the equation proposal by Bejan the numerical simulation using an explicit finite element method, which has a suitable formulation for inserting the effects of temperature and strain rate in the material. The results show that for the conditions evaluated the model proposed by Bejan (Eq. 4) is very close to the results obtained by the numerical simulation. Moreover, as EHISF is a process with large deformations and time-consuming, it would be necessary to include the terms of the energy of plastic deformation (E) and also the loss by convection to better represent the distribution of heat in the plate. [ABSTRACT FROM AUTHOR]

The Hybrid Coordinate Ocean Model (HYCOM) uses different vertical coordinate choices in different regions. In HYCOM, the prognostic variables include not only the seawater temperature, salinity and current fields, but also the layer thickness. All prognostic variables are usually adjusted in the assimilation when multivariate data assimilation methods are used to assimilate sea surface temperature (SST). This paper investigates the effects of SST assimilation in a global HYCOM model using the Ensemble Optimal Interpolation multivariate assimilation method. Three assimilation experiments are conducted from 2006-08. In the first experiment, all model variables are adjusted during the assimilation process. In the other two experiments, the temperature alone is adjusted in the entire water column and in the mixed layer. For comparison, a control experiment without assimilation is also conducted. The three assimilation experiments yield notable SST improvements over the results of the control experiment. Additionally, the experiments in which all variables are adjusted and the temperature alone in all model layers is adjusted, produce significant negative effects on the subsurface temperature. Also, they yield negative effects on the subsurface salinity because it is associated with temperature and layer thickness. The experiment adjusting the temperature alone in the mixed layer yields positive effects and outperforms the other experiments. The heat content in the upper 300 m and 300-700 m layers further suggests that it yields the best performance among the experiments. [ABSTRACT FROM AUTHOR]

magnetohydrodynamic (MHD) power generator system involves several subjects such as magnetohydrodynamics, plasma physics, material science, and structure mechanics. Therefore, the performance of the MHD power generator is affected by many factors, among which the load coefficient k is of great importance. This paper reveals the effect of some system parameters on the performance by three-dimensional (3D) numerical simulation for a Faraday type MHD power generator using He/Xe as working plasma. The results show that average electrical conductivity increases first and then decreases with the addition of magnetic field intensity. Electrical conductivity reaches the maximum value of 11.05 S/m, while the applied magnetic field strength is B = 1.75 T. When B > 3T, the ionization rate along the midline well keeps stable, which indicates that the ionization rate and three-body recombination rate (three kinds of particles combining to two kinds of particles) are approximately equal, and the relatively stable plasma structure of the mainstream is preserved. Efficiency of power generation of the Faraday type channel increases with an increment of the load factor. However, enthalpy extraction first increases to a certain value, and then decreases with the load factor. The enthalpy extraction rate reaches the maximum when the load coefficient k equals 0.625, which is the best performance of the power generator channel with the maximum electricity production. [ABSTRACT FROM AUTHOR]