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Conventional multi-cylinder drying of paper and board involves a mixture of conductive drying from steam-heated dryer cylinders and convective drying by the flow of heated air over the surface of the paper web in the pockets. Pocket ventilation is a critical component in assisting heat and mass transfer during the drying process but is the primary contributor toward removing evaporated water from the web. Air temperature, velocity, and humidity are critical parameters involved in the convective drying process. This paper covers an experimental study involving the design and development of a small lab-scale setup for convective drying of various grades of paper and board, monitoring multiple parameters like paper temperature, moisture content, air humidity, temperature, and velocity measured in situ as the drying proceeds with continuous and accurate sampling capabilities for all parameters in the sample and the system. Instantaneous drying rates, heat, and mass transfer coefficients were also deduced for every time step till the paper completely dried. Furthermore, the coefficients obtained were also reported in the form of dimensionless correlations, and the results were compared against traditional correlations used in the modeling of paper drying. This data will be useful in process development, modeling, design, and the paper drying process simulation. [ABSTRACT FROM AUTHOR]

Fingermarks used in forensic investigation are biometric elements widely utilized in identification thanks to their unique and classifiable characteristics. Despite numerous studies investigating fingermark development on different surfaces, few studies have addressed the skin surface of deceased individuals, given the challenging nature of this substrate. This study investigated the transfer and development of fingermarks on human skin that had been systematically deposited over the forehead, neck, and wrist. Additionally, gender, age, and the time elapsed since deposition were issued as additional factors impacting fingermark development. Therefore, we prepared a study setting representing a crime scene by modelling the scene and then utilized 400 fingermarks. The marks transferred to thermal paper were developed by applying ThermaNin and magnetic black fingermark powder as fingermark development methods and then photographed. They were then evaluated for their suitability for identification via scoring and statistical analysis. The results indicated that 36% of all marks obtained from the skin of living persons and 66% of those from skin surfaces of dead bodies received the highest score and were assessed as suitable for identification. Despite the negative effect of increased time since deposition, it was revealed that the ThermaNin method yielded better results than magnetic black fingermark powder. [ABSTRACT FROM AUTHOR]

To apply functional honeycomb panels (FHPs) in actual engineering projects, the heat transfer performance and intrinsic heat transfer mechanism of laminated honeycomb panels (LHPs, total thickness of 60 mm) with different structural parameters were investigated in this study by a heat flow meter. The results showed that (1) the equivalent thermal conductivity λequ of the LHP was almost independent of the cell size, when it consisted of a small single-layer thickness. Thus, LHP panels with a single-layer thickness of 15–20 mm are recommended. (2) A heat transfer model of LHPs was developed, and it was concluded that the heat transfer performance of LHPs depends greatly on the performance of their honeycomb core. Then, an equation was derived for the steady state temperature distribution of the honeycomb core. (3) The contribution of each heat transfer method to the total heat flux of the LHP was calculated using the theoretical equation. According to the theoretical results, the intrinsic heat transfer mechanism affecting the heat transfer performance of LHPs was revealed. The results of this study laid the foundation for the application of LHPs in building envelopes. [ABSTRACT FROM AUTHOR]

In the use of hot melt adhesives in the production of paper-based packaging, the controlled penetration of the adhesive is important to obtain rapid setting rates, good bond strength, and the efficient use of adhesive. Measuring adhesive penetration depth has been limited to cross-sectional images, but quantifying the depth of penetration is difficult from these images. No quantitative method is well established in the literature. Four different techniques are compared to quantitatively measure adhesive penetration depth. Two methods involve separating the paperboard from the adhesive layer. Two other methods use of silicone oil penetration and mercury porosimetry to measure the decrease of pore volume after the adhesive is applied. These methods are compared with samples generated for various parameters. Experiments were conducted using a typical hot melt glue on uncoated and coated paperboard sample. Cross-sectional images from Scanning Electron Microscopy (SEM) confirm the penetration of some samples. The accuracy and repeatability of these methods were compared. Because of some issues with trying to repeatably remove the paper layer for the weight and thickness methods, and the time and cost of the mercury porosimeter method, the silicone oil method is a nice method to characterize the adhesive penetration depth. [ABSTRACT FROM AUTHOR]

In this work heat transfer papers were loaded with a new core–shell pigment based on precipitating thin shell of titanium dioxide on a core of rice husk silica ash TiO2/RHSA to be applied in dye sublimation printing of textile fabrics. Besides, 0.1% (w/w) cationic polyacrylamide (CPAM) and 1% (w/w) bentonite (Bt) were also added sequentially to improve drainage and filler retention of the paper hand-sheets made from bleached kraft bagasse pulps. The effect of the new core–shell pigment on the mechanical and barrier properties, thermal stability and surface morphology of modified paper sheets were investigated. In addition, the study of transfer printability and ease of dye release from paper to fabric in this heat transfer printing of polyester fabrics using silk-screen printing under different transfer parameters were studied. Also, fastness measurements including washing, light and perspiration of printing polyester fabric were also estimated. [ABSTRACT FROM AUTHOR]

The heat and momentum transfer of crop pulp fibre suspensions were studied in a single pipe heat exchanger test loop. The data were produced at the pre-selected temperature, concentrations, and a range of flow rates. It was found that at the low fibre concentrations, the magnitude of heat transfer coefficient was higher than those of water data at the corresponding experimental conditions. However, the values progressively decreased below the water data at higher concentrations. The heat transfer data were affected by the variation of fibre characteristics, such as fibre flexibility, fibre length, fibre mechanical and chemical treatment, and the pulping methods used to liberate the fibres. The reduction of heat transfer coefficient was obtained with the enhancement of fibre flexibility observed by previous researchers for wood pulp fibres. In the present study, the characteristics of fibres and paper are correlated with heat and momentum transfer of suspensions of the fibres. Deviations in fibre properties can be monitored from the measurement of heat transfer coefficient or frictional pressure loss, and they can be adjusted by altering the degree of fibre refining treatment. Thus, the papers made from the fibre suspensions via in-situ monitoring could be uniform, consistent, and remain within the product specification. This could curb the rejected papers and ultimately reduce production costs and energy consumption. [ABSTRACT FROM AUTHOR]

For the development of functional honeycomb plates (FHPs) and efficient resource utilization of straw, based on the measurement of the equivalent thermal conductivity (λE) of paper honeycomb plates (HPs) and FHPs, including straw-core paper honeycomb plates (SHPs), under cold-left and hot-right conditions, the influence mechanism of the system geometry parameters on the convective heat transfer of HPs and the heat insulation performance of FHPs by fillers are discussed. The results are as follows. 1) Compared with the case of hot-above and cold-below conditions, the convective heat transfer ratio of HP increases substantially under cold-left and hot-right conditions. 2) The main heat transfer modes of the FHPs are radiative heat transfer between the wall (including the panel and side) and filling material and solid heat conduction in the filling material, supplemented by a small amount of heat conduction through air or local convection heat transfer in the void. 3) The higher the temperature is, the greater the FHP equivalent thermal conductivity, with little influence from the heat transfer direction. 4) It is relatively conservative to use the heat transfer effect of HPs and FHPs to evaluate that of beetle elytron plates (BEPs) and functional beetle elytron plates (FBEPs). This study lays a foundation for the application of multifunctional BEPs and HPs in building envelopes. [ABSTRACT FROM AUTHOR]

Modeling of the dryer section of a paper machine is of high importance in both designing and operation points of view. In this research, a novel thermodynamic and heat and mass transfer model has been introduced. The model is based on empirical equations of the literature and does not need fine discretization techniques such as finite difference method. The method used for calculation of convective heat and mass transfer coefficients of the dryer is a modification of the methods utilized in the literature. The trend of paper and air temperature in the dryer, the steam consumption of each cylinder, as well as the trend of drying process throughout the dryer has been calculated. Overall results of the dryer such as the total evaporated water and the specific steam consumption of the dryer have been obtained too. The results have been validated with experimental data of a previous research in the literature and show a relatively good agreement with the experimental data. Finally, the sensitivity of the results to some main parameters has been analyzed. [ABSTRACT FROM AUTHOR]

Some errors exist in the above paper. [ABSTRACT FROM AUTHOR]

Establishing and optimizing a distributed parameter thermal path model for transformer windings is an important means to analyze the hot-spot temperature of the windings; furthermore, in the process of improving the thermal path model of transformers and improving the accuracy of their models, the thermal characteristics of the insulation paper are extremely important. A microscopic thermal contact resistance model was established for the contact interface of insulation paper and copper, according to the microscopic morphology parameters of copper and insulation paper observed by atomic force microscopy, the thermal contact resistance under different temperatures was calculated. A dual heat flow test platform was built to test the heat transfer behavior of four different thickness insulation papers under four temperatures, and the thermal contact resistance and thermal bulk resistance with temperature were analyzed. The results show that as the temperature increases, the thermal resistance of the insulation paper becomes larger and the thermal conductivity decreases. The average error between the experimental and theoretical values of the thermal contact resistance under four temperature points in the study is 6.6%. The results provide a data support for establishing and optimizing transformer heat generation and heat transfer models. [ABSTRACT FROM AUTHOR]

The extended meniscus and the intermolecular and capillary forces that govern its behavior and connection to change-of-phase heat transfer have been the subject of an increasing body of research over the past 50 years. We have been fortunate to be at the forefront of this effort starting from the development of a capillary feeder, in Earth's gravity, to stabilize film boiling to running a series of transparent heat pipe experiments aboard the International space station hoping to better understand the role of intermolecular forces in microgravity. The use of ellipsometry and interferometry to highlight the location and state of the vapor-liquid interface have been key to these studies and have helped to uncover many new, interesting, and sometimes unexpected phenomena associated with fluid flow and change-of-phase heat transfer. [ABSTRACT FROM AUTHOR]

Drying of paper during 2000–2018 is reviewed. The review includes new drying processes, multi-cylinder dryers, tissue and impingement drying, TAD-drying, infrared drying and energy use for drying of paper. It includes general aspects of infrared dryers but not drying of coated papers. Paper quality aspects, paper shrinkage and paper isotherms are not included. Impingement drying has been the most successful new technology with several applications while others such as impulse drying has not been commercialized mainly due to problems with paper quality parameters. One promising development is the introduction of steel instead of cast iron cylinders with increased heat transfer reducing the number of cylinders. Future research should focus on modeling the internal transport phenomena and to couple these phenomena to paper shrinkage and quality parameters. The influence of the fabric for the drying process needs more attention, understanding the drying process for new components such as microfibrillar cellulose in the stock and reducing energy use and increasing the amount of renewable energies for drying of paper. [ABSTRACT FROM AUTHOR]

Some errors exist in the above paper. [ABSTRACT FROM AUTHOR]

Some serious errors exist in the above paper. [ABSTRACT FROM AUTHOR]

Rome represented and excellent opportunity by bringing together members of the international heat and mass transfer community in a unique location that offered historical and artistic attractions, a wide array of accommodation and transportation options, and meeting facilities of the highest level. The ICCHMT2019 organizers were Prof. Abdulmajeed Mohamad from University of Calgary (Canada), Prof. Jan Taler from Cracow University of Technology (Poland), Prof. Ali Cemal Benim from Duesseldorf University of Applied Sciences (Germany), Prof. Roberto de Lieto Vollaro from Roma TRE University (Italy), Prof. Andrea Vallati from Sapienza University of Rome (Italy) and the Scientific Secretary Dr. Gabriele Battista from Roma TRE University (Italy). This Special Issue presents 22 papers selected from 12th International Conference on Computational Heat and Mass Transfer (ICCHMT2019). [Extracted from the article]

This document is a special issue of the Heat Transfer Engineering Journal, dedicated to the research studies presented at the International Conference on Thermal Analysis of Energy Systems. The conference, organized by the Heat Pump Research Institute in India and the Department of Mechanics at Al-Farabi Kazakh National University in Kazakhstan, took place virtually in December 2021. Out of over 100 papers presented, eight were selected for this special issue, covering topics such as thermodynamic analysis of thermal systems, heat exchangers, and heat transfer enhancement studies. The papers were reviewed by experts in the field and revised accordingly. The document expresses gratitude to the editor, authors, and conference co-organizers, and announces that the next conference is planned for June 2024. The author of the document, Murugesan Mohanraj, is a professor in Mechanical Engineering and has extensive experience in renewable energy and heat transfer research. [Extracted from the article]

Drying of sewage sludge is typically modeled as simultaneous heat and mass transfer phenomena. The capability of conventional models to take into account crust formation, cracks, and shrinking is limited. Artificial neural networks (ANNs) are suitable tools for dynamic representation of drying processes; however, obtaining a suitable database is a resource consuming task. Based on the Taguchi method, nine experiments were defined to set up a training database and to develop an ANN model. A high Pearson correlation coefficient was verified when comparing the drying kinetic curve generated by the ANN model with the one obtained during the validation experiments. [ABSTRACT FROM PUBLISHER]

Thermal switches control thermal circuits and are widely used in electronics and engineering. Shape-memory alloys can be deformed by heating, which is widely used as a driving part for thermal switches by many research groups. Shape-memory alloys are inappropriately used in thermal switches as the heat transfer components because of their lower thermal conductivity. Components responsible for the heat transfer and driving are usually separated from each other inside the device. Such design increases the complexity of the device and its production cost. By combining high thermal conductivity and self-driving properties of the shape-memory alloys, the structure of the thermal switch can significantly not only simplify its design but also can improve its performance. In this paper, we implemented two-way memory alloy as the drive device. Graphene paper was used to cover the surface of the memory alloy. Self-actuation of the shape-memory alloy and high thermal conductivity of graphene enhance heat conduction of the switch. The resulting device has a simple structure, is flexible, stable and easy to operate. We thoroughly studied structure and working principle of this thermal switch. Both simulations and experimental tests were performed to analyze thermal conductivity of the switch. We obtained a switch ratio equal to 54.0 ± 24.3. Our thermal switch is very promising for the advanced thermal management of the electronic devices. [ABSTRACT FROM AUTHOR]

Insolation calculations for solving the two-body problem have been analyzed. The errors associated with the simplification of the calculation algorithm of insolation and disregard (simultaneously) of the attraction of planets of the solar system and their satellites in calculations of the Earth's irradiation have been indicated. The use of the method of equivalent latitudes in paleoclimatology has been shown to be inconsistent. The need to take into account changes in the meridional insolation gradient, which regulates the meridional heat transfer from the equator to polar regions, in paleoclimatology and paleogeography has been substantiated. [ABSTRACT FROM AUTHOR]

The paper presents the results of investigations on the thermal properties of cellulose and aramid paper impregnated with various liquid insulations. The liquid insulations investigated were mineral oil, synthetic ester, and natural ester. The heat transfer coefficient of the liquid was calculated on the basis of measurements of the thermal expansion, specific heat, density, thermal conductivity and kinematic viscosity of the liquid insulations. Temperatures in the paper and liquid insulations were calculated. The results allow to select the best paper and liquid insulations which provide the most effective cooling in transformers. [ABSTRACT FROM AUTHOR]

Worldwide, the need for thermal insulation materials used to increase the energy performance of buildings and ensure indoor thermal comfort is constantly growing. There are several traditional, well-known and frequently used thermal insulation materials on the building materials market, but there is a growing trend towards innovative materials based on agro-industrial waste. This paper analyses the performance of 10 such innovative thermal insulation materials obtained by recycling cellulosic and/or animal waste, using standardised testing methods. More precisely, thermal insulation materials based on the following raw materials were analysed: cellulose acetate, cigarette filter manufacturing waste; cellulose acetate, cigarette filter manufacturing waste and cigarette paper waste; cellulose acetate, waste from cigarette filter manufacturing, waste cigarette paper and waste aluminised paper; cellulose from waste paper (two types made by two independent manufacturers); wood fibres; cellulose from cardboard waste; cellulose from waste cardboard, poor processing, inhomogeneous product; rice husk waste and composite based on sheep wool, recycled PET fibres and cellulosic fibres for the textile industry. The analysis followed the performance in terms of thermal insulating quality, evidenced by the thermal conductivity coefficient (used as a measurable indicator) determined for both dry and conditioned material at 50% RH, in several density variants, simulating the subsidence under its own weight or under various possible stresses arising in use. The results showed in most cases that an increase in material density has beneficial effects by reducing the coefficient of thermal conductivity, but exceptions were also reported. In conjunction with this parameter, the analysis of the 10 types of materials also looked at their moisture sorption/desorption capacity (using as a measurable indicator the amount of water stored by the material), concluding that, although they have a capacity to regulate the humidity of the indoor air, under low RH conditions the water loss is not complete, leaving a residual quantity of material that could favour the development of mould. Therefore, the impact on indoor air quality was also analysed by assessing the risk of mould growth (using as a measurable indicator the class and performance category of the material in terms of nutrient content conducive to the growth of microorganisms) under high humidity conditions but also the resistance to the action of two commonly encountered moulds, Aspergillus niger and Penicillium notatum. The results showed a relative resistance to the action of microbiological factors, indicating however the need for intensified biocidal treatment. [ABSTRACT FROM AUTHOR]

Effective use of energy in various branches of economy is one of world trends in development of power engineering. Relevant energy consumption occurs during exploitation of buildings, so there is still potential to diminish it as far as heating, ventilation, and air conditioning are concerned. Particularly in summer season, the choice of respective roofing colour can play a decisive role for the heat flux transferred to the inside of the object. Decrease of heat flux causes a lower heat burden to the building and lower power consumption by the air conditioning systems. In winter, on the contrary, heat flux transferred to building's interior should be higher, as a result, demand of energy for heating will be lower. However, calculations of the heat flux require that energy balance must be made for the object. Unfortunately, not all producers of roofing covers inform about the values of reflectivity and thermal emissivity of their products, which is, in turn, necessary for calculations. In the present paper, research methodology elaborated by authors is proposed for determination of thermal emissivity of roofing covers. The paper presents test stand, methodology, and research results for roofing paper in blue colour (as an example) for which the thermal emissivity is an unknown parameter. [ABSTRACT FROM AUTHOR]

The contact angle (CA) of a water droplet on the polished aluminum surfaces is usually between 60° and 90°. This paper discusses a tuned bulk micro-manufacturing approach for transforming the surface topology of aluminum simultaneously at the micro- and nano-length scales, thereby significantly influencing its wetting characteristics. The approach is cheap, easy to implement, and scalable. The treated aluminum surfaces appeared like roughly polished surfaces at the macroscale and were found to be robust and non-toxic. They exhibited a paper towel effect by showing extreme surface wettability (CA of zero) to many industrial liquids, i.e., wetting on these surfaces is only a function of the surface roughness but not the fluid type. This extreme wetting ability to multiple liquids (or ultra-omniphilicity) was generated by sequentially creating a sub-surface micro- and nano-cavity architecture with nano-cavities within the embryos of micro-cavities interconnected by a network of micro-grooves. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive review of significant studies that are relevant to thermal energy storage technologies using phase change materials (PCMs). The review focuses on the techniques applied to enhance the performance of thermal storage systems and the methods used to analyse the heat transfer problems in PCMs. In addition, this paper reviews the published results and discussions on the heat transfer intensification methods including application of fins, filling materials, nano-fluids, nano-particles, microencapsulation and the thermal conductivity enhancement method. Furthermore, the experimental and mathematical methods to enhance the thermal conductivity of PCMs are summarised, and the methods used to determine the nanofluid dynamic viscosity in recent investigations are also listed and discussed. The focus of this review is to provide a solid basis for the identification of the optimal design for the various heat transfer applications using PCM. [ABSTRACT FROM AUTHOR]

Pulsating Heat Pipe (PHP) is an emerging efficient heat transfer device, that transfers heat passively through oscillating motions of liquid slugs and vapor plugs within the device. PHP is of high effective thermal conductivity with great potential in heat transfer management for various applications. The objective of this review paper is to summarize and analyse the applications of PHP in various fields that have been reported in the open literature, emphasizing on studies reported in past half decade. The thermo-hydraulic behaviour of PHP is influenced by numerous geometric and operational parameters, which are discussed in detail in the first part of the paper. The thermal performance of the PHP under rotation condition, which is seldom discussed in previous review articles, is also discussed. These parameters act individually and in tandem to alter the performance of PHP, which makes its prediction extremely difficult. However, the benefit of numerous influencing parameters is that they can be altered to make PHP suitable for various applications. These highly variable configurations make PHP suitable for applications such as the transfer of absorbed solar energy to the location of interest, waste heat recovery, thermal management of electric vehicle batteries, fuel cells, cooling of electronic components etc. PHPs are recently being studied for applications in cryogenics and cooling of cutting tools in the machining process also. In addition, novel applications of PHP such as high-performance fins for heat exchangers, cooling of building roofs etc. are also being reported. All these applications of PHP reported in the open literature are reviewed and summarized in the present article. [ABSTRACT FROM AUTHOR]

This paper studies the optimization design of capillary heat exchangers and their innovative engineering applications in buildings. The purpose of this study is to use a capillary heat exchanger as the front-end device of the heat pump in coastal areas to extract energy to facilitate the application of renewable energy in buildings. Firstly, in this paper, the main factors of capillary heat transfer efficiency were explored in areas near the coast. Secondly, for the sake of improve the heat transfer efficiency of the capillary heat exchanger, numerical calculations were carried out on the heat transfer of the capillary in the case of inconsistent operating patterns in the summer and winter months, respectively. The results showed that when the daily working time of the capillary heat exchanger was 8 hours, the temperature difference of the capillary inlet and outlet was 2.1 ℃. And the heat transfer rate was 87.1 W/m² . In summer, the temperature difference of the capillary inlet and outlet was 2.6 ℃. And the heat transfer rate was 107.8 W/m² . This article helps to promote innovative and sustainable technologies in coastland development, such as capillary heat exchangers and heat pumps, which could used in renewable energy extraction and building utilization in near coastal areas. [ABSTRACT FROM AUTHOR]

The influence of conjugate heat transfer based on radiation and magnetohydrodynamic utilization is an attractive research area, with progressive features; it has many applications in thermal engineering, heat exchangers, cooling phenomenon, magnetic cell separation, energy production, hyperthermia, etc. Following the motivating significances of the current research topic, this paper explores the influences of an electrically conducting and radiating fluid with internal friction, heat generation and thermal radiation embedded in a porous medium past a flat permeable plate. The boundary layer equations are dimensionally transformed and solved numerically using implicit finite difference technique called the Keller-box method. The effect of various fluid obeying parameters such as magnetic field, viscous dissipation and heat generation on the flow factors such as velocity and temperature are graphed and discussed in this paper. Growing heat source, energy inside the fluid boosts, thereby increasing the energy of the flow. Increase in generation of energy reduces the viscosity of the flow reduces thereby increasing the velocity of the flow particles. [ABSTRACT FROM AUTHOR]

This paper describes the fundamental characteristics of cavitation in non-Newtonian liquids and bubble dynamics and then applies them to the domains of bioengineering and biomedicine. The goal of this paper is to examine how Newtonian nanomaterial flows hydromagnetically when subjected to a spinning disc considering such biomedical and bioengineering applications. The vertical axis of the disc rotates with a uniform angular frequency. The fundamental mathematical expressions are governed by the Navier–Stokes equations with the Maxwell equations of magnetism, we obtained ordinary differential equations utilizing Von Kármán's similarity transformations. Additionally, the effects of the magnetic field and radiation restrictions are considered. The RK-4 technique is used to solve the transmuted nonlinear ODEs. The analysis of MATLAB generated flow profiles has looked for changes in the values of key parameters. It is discovered that an increase in the thermal radiation parameter causes a decrease in the nanofluid temperature while an increase in the volume fraction of magnetite nanoparticles causes an increase. The skin-friction and heat-transfer rate at the disc are highly influenced by its rotational, the porosity of the porous media, thermal radiation and nanoparticle size. The rotational parameter, which regulates the disk's rotation, is a result of the rotating phenomenon. The research demonstrates that when the disk's rotation increases, the fluid motion accelerates in both the radial and cross-radial directions. Additionally, increasing the Prandtl number significantly improves heat transport, and a higher value for the rotation parameter shows a lesser concentration phenomenon. Additionally, the Nusselt number shows a decrease curve for a changeable thermal conductivity parameter. Finally, the current research can effectively close a gap in the physique of knowledge. [ABSTRACT FROM AUTHOR]

Elastocaloric cooling is emerging as a promising alternative to conventional vapor compression systems due to its potential for energy savings and significant temperature lift compared to other solid-state cooling technologies. This technology harnesses the latent heat associated with the martensitic phase transition of shape memory alloys to generate the desired cooling or heating effect. This paper comprehensively reviews the fundamentals of elastocaloric cooling systems, including the thermodynamics cycle and various materials used. It also presents the latest advancements in elastocaloric systems, focusing on heat transfer enhancement, actuator development, and prototype summaries. Additionally, this paper introduces a new non-dimensional performance parameter to evaluate different elastocaloric prototypes and discusses key aspects necessary to achieve potentially high-performance elastocaloric devices. Finally, we propose an approach for future elastocaloric device development. [ABSTRACT FROM AUTHOR]

• The experimental research of 2-FTE and 6-FTE were developed. • The effect of the number of fins, the angle of the fins and the way the fins are connected to the tube on the performance of the fin evaporator has been studied. • The influence of different fin structures on the cooling capacity per unit mass is analyzed. • The influences of different fin structures on heat transfer coefficient and fin efficiency were analyzed. Tube evaporators are widely used in cold storage, the single-tube two-fin tube evaporator (2-FTE) has the problems of poor heat transfer performance and low tube utilization. In this paper, a numerical simulation method is used to optimize the structure of 2-FTE, and a single-tube six-fin tube evaporator (6-FTE) structure is designed to achieve an increase in the cooling capacity per unit mass of the tube and heat transfer efficiency. Based on this, the heat transfer performance test bench of the tube evaporator is constructed, and the heat transfer performance of 2-FTE and 6-FTE is compared and tested according to the evaluation indices of cooling capacity, fin efficiency and cooling rate in the test environment from −32 °C to −6 °C. The results show that 6-FTE saves between 10.6 and 17.1% of tube consumption compared to 2-FTE for the same cooling capacity. The cooling capacity per unit tube length of 6-FTE increased by 43.9–64.7%, the cooling rate increased by 28–41%, the overall fin efficiency increased by 3.5%, and the heat transfer performance was better than that of 2-FTE, which was consistent with the simulation conclusions and in line with optimization goals. Therefore, the 6 FTE structure proposed in this paper can be an effective solution to save the manufacturing costs of refrigeration equipment for cold storage. [ABSTRACT FROM AUTHOR]

The performance of the Plate Indirect Evaporative Cooler (PIEC) can be effectively improved by incorporating baffles in the dry channel. However, in the dimensional influence of the baffles on PIEC performance there remains a research gap. In order to investigate the impact of baffle dimensions on the wet bulb efficiency, namely the average heat transfer coefficient and the cooling capacity of the PIEC, this paper proposed and verified a three-dimensional numerical model and method based on the species transport model and the Euler wall film model. At the same time, in order to obtain the equilibrium point between the enhanced heat transfer performance and the additional resistance induced by baffles, a comprehensive performance evaluation index is introduced. The results indicate that, under the same conditions, (1) the baffle effect on PIEC performance is significant at a lower inlet air velocity, and the wet bulb efficiency of the PIEC with baffles can be improved by 22.8%; (2) the baffle effect on PIEC performance is negative if its relative length exceeds 60% or the primary air inlet velocity surpasses 4 m/s under the conditions specified in this paper; and (3) the baffle effect on PIEC performance is significant when its channel height is lower and its channel width is larger, and the wet bulb efficiency of the PIEC with baffles can be improved by 29.3%. [ABSTRACT FROM AUTHOR]

The building envelope is the interface between the external atmospheric conditions and the indoor environment. It contributes to approximately 60%-70% of the heating and cooling load. The building envelope constitutes walls, fenestrations, and roofs from which thermal transfer from the roof is significantly very high compared to walls in low-rise buildings. This research paper aims to provide recommendations for energy-efficient roof design considering roof form, material, and external coating suitable for various climate conditions of India. The paper's methodology consists of a literature review of related research papers, learnings from the roofing system of energy-efficient building case studies, and all possible energy-efficient roofing systems that would be simulated for energy efficiency and thermal comfort in five climate types of India. The expected outcome of this paper would be in the form of recommendations for roofing systems in different climate type and their potential for energy saving from the highest to the lowest. This research would be done in three stages viz, Step-1: Literature Review and case study of best practices: A review of the related literature and best practices examples would be done to formulate the maximum possible cases for the simulation. Step-2: The roofing systems, including building form, material (Thermal and insulation), and finishes (reflectance), would be simulated one by one for various climate types of India (composite, hot & dry, warm and humid, moderate and cold) to optimize energy efficiency and payback period. Step-3: Special roof types like Green roofs, cool roofs, Photovoltaic roofs, roof ponds, and the like are simulated and compared for their effectiveness in selected climate types. Based on the literature review, simulation results, and analysis, the recommendations are framed for energy-efficient roofing systems in the selected climate type with respect to heat transfer through the roof and thermal comfort. [ABSTRACT FROM AUTHOR]

The main objective of the present article is to investigate the hydromagnetic particle Reiner-Rivlin fluid flow in an asymmetric (divergent) channel. The non-dimensionalized equations solved by the shooting method. The graphs are intended to examine how different developing parameters affect the thermal and velocity fields. The effects of various parameters on skin friction and the rate of heat transmission along channel walls are investigated using tabular data. The current results are in admirable agreement with the published data. The fluid velocity delineates in the first portion of the channel and rockets up in the second when the inelastic parameter increases. An increase in cross-flow Reynolds number is accompanied by an increasing tendency in particle temperature. Several areas, like metal steam resistors, fiber suspension in paper manufacture, etc., are significantly impacted by the magnetic field's action on Reiner-Rivlin fluid through asymmetric channels. [ABSTRACT FROM AUTHOR]

Abstract: Carbon paper, a fibrous material, is often used as the gas diffusion layer in polymer electrolyte membrane (PEM) fuel cells, which are being vigorously developed as a zero-emission power source for transportation applications. The temperature field and heat transfer in this material is determined by its thermal conductivity and diffusivity, which are directly dependent on the operating temperature. In this work, we use a quasi-steady method known as the thermal capacitance (slug) method to experimentally measure the through-plane thermal conductivity of TORAY carbon paper for a temperature range from −50 to +120°C. The effects of compression and PTFE loading on the overall thermal conductivity are also investigated. Compression leads to a decrease in thermal resistance between the carbon fibers; hence, an increase in the overall thermal conductivity. However, it is also found that this thermal resistance is highly dependent on the temperature and the PTFE loading. In contrast with our in-plane thermal conductivity measurements from a previous study, the through-plane thermal conductivity is found to increase with an increase in temperature in this study. This finding suggests that the thermal expansion of the carbon fibers is a direction dependent quantity. [Copyright &y& Elsevier]

Abstract A coupled numerical multi-physics model is developed to study the generation and variation mechanisms of friction torque, including fluid lubricating, micro-contact, sliding and heat transfer among the friction components. The engagement experiment is conducted to verify the accuracy of numerical model and investigate the stability of friction torque. The results show that the most significant operating factor affecting the friction stability is the applied pressure, followed by the rotating speed and the ATF temperature. Simultaneously, the operating factors have great influence on the torque response, engagement time and temperature rise. Moreover, the growth model of friction torque can be divided into two categories: one is increasing linearly and the other is concave parabolic rising. Highlights • A coupled numerical multi-physics model is presented to study the generation and variation mechanisms of friction torque. • The bench test is conducted to verify the accuracy of numerical model and investigate the stability of the friction torque. • The most significant operating factor affecting the friction stability is the applied pressure, followed by the rotating speed and ATF temperature. [ABSTRACT FROM AUTHOR]

The article offers information on fifth International Symposium on Heat Transfer and Energy Conservation (ISHTEC2016) held on November 11-14, 2016 in Guangzhou, China. Topics discussed include new heat transfer theories, heat transfer enhancement technologies, micro/meso-heat transfer, and the heat transfer problems in energy use systems.

Steam heating characteristics of wet paper are studied experimentally and numerically. Experimental results show that suction pressure enhances energy absorption in the wet paper and decreases temperature difference in the paper thickness direction, and effects of suction pressure strongly appear in the high-permeability paper. Experiments also indicate that the absorbed energy rate is decreased with increasing in the heating time. Temperature, moisture, and pressure distributions in the paper thickness direction are calculated from the numerical simulation model. From the numerical simulation it is found that increasing of the moisture content and thickness of the condensation region reduce the absorbed energy rate. [ABSTRACT FROM AUTHOR]

Thermal conductivity of paper coatings is increasingly important in the performance of many printing processes, including traditional heatset web offset and thermal papers, as well as digital processes, such as electrophotography. This work studies the extension of a Modified Lumped Parameter Model, previously used successfully to describe talc coatings, to model the thermal conductivity–coating structure relationships of calcium carbonate (gcc: 60 wt% < 2 μm) coatings. A series of compact tablets were used to provide experimental values of thermal diffusivity and conductivity. The samples studied covered a range of latex binder addition levels, namely 0–25 parts, based on 100 parts pigment, of 0.2 μm styrene acrylate latex. Combining the observed thermal properties with knowledge of the pore structure changes induced by the latex addition, it is possible to establish initial correlation with the model, in which the connectivity of the structure is increased at low latex dose illustrating the initial increase in effective thermal conductivity. The practically hard sphere properties of the latex used, combined with the broad size distribution of the gcc, produce a disruptive packing effect as the dose level increases, such that the conductivity reflects a competition between the increasing connectivity provided by the latex versus the increasing relative pore size in the network structure. It is recognized that the fixed pigment volume in the model unit cell diverts from a true representation of the residual porosity. At the highest latex dose levels, the intrinsically less conducting properties of the latex begin to dominate. [ABSTRACT FROM AUTHOR]

This comment deals with the proposed accuracy and the interpretation of results of experimental measurements of the temperature dependent thermal conductivity of porous heat storage media carried out by the authors of the original paper. We argue that the described reduction of the thermal conductivity of the specimens is probably mainly an artefact because boundary conditions of the used measurement device have been disregarded. Furthermore, we make some suggestions how to repeat the measurements to gain more proper results. [ABSTRACT FROM AUTHOR]

The fabrication of most current thermal insulation materials from polymeric foams has created an unfavorable impact on the environment. With the aim of reducing the use of foam plastic, this paper focuses on honeycomb paperboard, an alternative thermal insulation material which is recyclable and cost-effective, and evaluates its heat transfer performance under different conditions. The experimental results show the effective thermal conductivity of honeycomb paperboard increases as the honeycomb height or the side length increases. This paper also establishes a novel theoretical model based on a newly developed convective heat transfer correlation to predict the effective thermal conductivity under different conditions. The model's results conform well to the experimental results, and the effect of convective heat transfer is investigated quantitatively using this model. As the vertical adiabatic boundary surfaces are replaced by honeycomb walls, the convection heat transfer strictly depends on the thermal boundary condition of the honeycomb walls and highly depends on honeycomb height and side length. • The novel theoretical models involving convective heat transfer are established under different conditions. • The different heat transfer paths are quantitatively investigated based on the proposed models. • Under the condition of hot-above and cold-below, convective heat transfer in honeycomb paperboard increases as the honeycomb height increases, but decreases as the side lengths increases. • Under the condition of cold-above and hot-below, convection heat transfer in honeycomb paperboard increases as the honeycomb height or the side length increases. [ABSTRACT FROM AUTHOR]

Effective sludge management is increasingly critical for pulp and paper mills due to high landfill costs and complex regulatory frameworks for disposal options such as sludge landspreading and composting. A novel continuous biodrying process has been developed to dry mixed sludge so that it can be combusted efficiently in a biomass boiler for energy recovery. Modeling this process is important in order to better understand the transport phenomena in the biodrying reactor and for design and scale-up of the process. A one-dimensional (1D) distributed model for heat transfer coupled with mass and biological transfer phenomena is introduced in this article that shows that the temperature of the sludge matrix is a critical parameter. The model assumes lumped parameters in the gas flow direction and distributed parameters in the (vertical) solids flow direction. Bioheat as a source term and evaporative heat as a sink term are critical issues. In order to evaluate the parameters and assess the model accuracy, a series of experiments was performed. The matrix temperatures predicted by the model were found to be in reasonable agreement with the experimental results, showing that the main transport phenomena were reflected in the model. Larger discrepancies between the water removal rates predicted by the model and the experimental values were indentified at higher aerobic exothermicity, which can be attributed to the complex mechanisms governing the growth cycle of mesophilic and thermophilic bacteria. A dimensionless analysis was performed to identify key dimensionless groups as well as the most dominant transport phenomena in the biodrying process. The results confirmed that convection processes dominated heat transfer at the top of the reactor, and the exothermic aerobic bioenergy dominated at its bottom. [ABSTRACT FROM AUTHOR]

Purpose: The coating process is broadly employed in the manufacturing of wallpapers, adhesive tapes, wrapping, protection of fabrics and metals, X-ray and photographic films, beautification, books and magazines, film foils, magnetic records, coated paper, etc. Design/methodology/approach: In this study, an incompressible flow of non-Newtonian fluid is modeled to inspect the rheological behavior of finite coating thickness in the reverse roll coating process. With the assistance of lubrication approximation theory (LAT), the dimensionless form of governing expressions is simplified. Exact solutions for distributions for velocity, flow rate, temperature and pressure gradient attained utilizing perturbation technique and their variation is presented as well as discussed in graphs. Meanwhile, some important factors from an engineering perspective including coating thickness and transition point were calculated mathematically and are displayed in a tabular manner. Also, streamlines are drawn to observe the flow pattern. Findings: Prandtl fluid parameters provide a controlling factor to regulate the flow rate, velocity, coating thickness, and pressure gradient leading to an efficient coating process. Moreover, the Brinkman number and Prandtl fluid parameters significantly improve the temperature distribution. Originality/value: In the literature, this study fills a gap in the theoretical prediction of coating thickness rheologically influenced by Prandtl fluid in reverse roll coating process. [ABSTRACT FROM AUTHOR]

Fouling of heat exchangers in the chemical industry, oil & gas industry, district heating, power plants, among others, results in a loss of performance which leads to production stops for cleaning and therefore increased operation costs. One approach to mitigate fouling is to alter the properties of the metal surface. A coating to be successful in any plate heat exchanger (PHE) application needs to have a good adhesion to the metal but also keep the heat transfer through the metal plates as unaltered as possible. This requires a thin coating with a relatively good thermal conductivity. The plates in a PHE are subjected to plate-to-plate contact point wear when in operation which also puts an extra requirement for the coating. To be suitable, the coating needs to have a good mechanical stability to resist this plate-to-plate wear. Alfa Laval has a long experience in coating plates for diverse applications and in this paper two case studies will be presented. One in the paper industry and the other in the biofuel industry. A new type of multilayer Teflon™ coating from Chemours was used, specifically designed to show excellent fouling release properties along with limited thicknesses (30–50 microns). [ABSTRACT FROM AUTHOR]

In this study, we propose a novel technique for fabricating paper-based analytical devices (PADs) using a wax-based thermal-transfer printer and a thermal laminator, which allows prototyping and roll-to-roll mass production of PADs without utilizing widely used conventional wax printers. This fabrication scheme involves two-sided patterning to form hydrophobic barriers and an ink ribbon that contains sufficient wax content to form hydrophobic barriers without undesirable components or additives. First, a thermal-transfer printer forms positive patterns on the ink ribbon for the front and back sides of the device design. Subsequently, a laminator performs the two-sided thermal transfer of the patterns from the ink ribbon to a paper substrate and the thermal formation of hydrophobic barriers for channels. The hydrophobicity of the prepared ink is similar to that of ink used in wax printers and exhibits excellent stability in organic solvents and surfactants. Hydrophobic barriers and channels were successfully formed using various paper substrates typically used for PADs. The two-sided scheme allows the formation of 3D channels, including vertical paths in a single paper substrate. The utility of the proposed fabrication technique was demonstrated using a dip-type 3D PAD for sensing glucose. [Display omitted] • A novel wax-based fabrication scheme for paper-based devices has been constructed. • This scheme uses a thermal-transfer printer, an optimized ink ribbon, and a laminator. • Hydrophobic barriers formed via this scheme exhibited excellent properties. • This scheme involves two-sided printing providing 3D channels in a single paper. • A dip-type PAD utilizing the features of this fabrication technique is proposed. [ABSTRACT FROM AUTHOR]

Some errors exist in the above paper. [ABSTRACT FROM AUTHOR]

They found that this novel loop heat pipe can start up and run successfully under different working modes and the heat dissipation capacity of a set of loop heat pipes can reach 250 W at room temperature. The series of UK Heat Transfer Conference (UKHTC) has been organized under the auspices of the UK National Heat Transfer Committee since 1984. In the seventh paper, Ren et al. conducted the parametric analysis of a novel photovoltaic/thermal system using amorphous silicon cells and micro-channel loop heat pipes. [Extracted from the article]