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Modern medicine has taken energy loss during cilia beating in the human stomach, which under some circumstances causes blood flow to become acidic, very seriously. In current report covering a whole advancement and results for the impact of Rabinowitsch model with cilia-driven flow analysis with the help of ciliary beating in a cylindrical tube. The fluid is incompressible, and layers of fluid do not mix. The fluid flow with heat and mass transfer is firstly modeled in wave and then transformed into fixed frame. Exact solutions for stresses, temperature velocity, and concentration profiles whereas numerical pressure rise is obtained subject to relevant boundary conditions. The behavior of incipient parameters is shown graphically (plotted in MATHEMATICA 13.0) in the results section. The key findings obtained from graphical results show that maximum magnitude for velocity and temperature is achieved in middle layer of fluid whereas in the outer layer concentration profile is maximum. The current study may help researchers to develop new treatments for diseases such as cystic fibrosis, in which impaired ciliary function leads to mucus accumulation in the lungs. The attained exact and numerical outcomes are novel and offered here for first time in literature. [ABSTRACT FROM AUTHOR]

Spray dry absorption flue gas desulfurization technology is widely employed to control sulfur dioxide emissions from industrial pollutant gases. This study employs the multiphase particle-in-cell method to numerically simulate gas–solid heat transfer, SO 2 removal processes, and the effect of operating conditions in the SDA reactor. The flue gas desulfurization model used has been experimentally validated. The results indicate that flue gas and slurry droplets exhibit swirling flow along the reactor walls, forming gas vortices at the top and near the outlet. The temperature and Reynolds number of slurry droplets show minimal variation when particle size is below 43 μm. The heat transfer coefficient of slurry droplets is notably higher at the reactor top and increases with the slip velocity of the droplets. Furthermore, the CaSO 3 volume fraction increases with longer residence times of the slurry droplets in the reactor. When the height and diameter of the main reaction area are lower than 14 m and 8.5 m, respectively, the SO 2 mass fraction in the central area undergoes significant changes. The SO 2 inlet concentration is negatively correlated with desulfurization efficiency, whereas the slurry injection speed, along with the diameter and height of the main reaction region, are positively correlated with desulfurization efficiency. Among these factors, the SO 2 inlet concentration and the height of the main reaction region have the most substantial impact on desulfurization efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biodiesel production in unconventional reactors is critically discussed. • Mixing improved in static and chaotic mixers, cavitation reactor, OFRs, and Microreactor. • Heat and mass transfer are also facilitated by unconventional reactors. • Biodiesel separation was eased in reactive distillation and membrane reactors. • Plasma reactor reduced the reaction time and avoided catalyst for biodiesel production. This review discussed unconventional reactors for biodiesel production including static and chaotic mixers, hydrodynamic cavitation reactor, oscillatory flow reactor (OFR), rotating/spinning-tube reactor, reactive distillation, plasma-, spiral-, membrane-, ultrasonic-, microwave-, and microchannel reactors. Mixers and OFR eased biodiesel production with improved mixing, reduced methanol consumption, and faster reaction time. Cavitation and ultrasound reactor intensified oil/catalyst surface area, mass transfer, and transesterification reaction. Rotary/spinning tube reactors enabled shear stress on oil/alcohol films, providing a high surface area/volume ratio and high interactions between the reactants. Plasma reactor avoided catalyst use and enabled biodiesel production 20 – 25 folds faster than the conventional reactor. Reactive distillation with membrane reactors avoided the separation issue. Spiral reactor facilitated enhanced heat transfer between the reacting mixtures with net energy ratio and energy efficiency of 0.92 and 0.98, respectively. Microwave reactors enabled local heating of reactants and resulted in uniform heating of the reaction mixture. Microreactors enabled short diffusion distance, improved surface area/volume ratio, and enhanced heat and mass transfers than conventional reactors. Thus, the unconventional reactors appeared promising to intensify biodiesel production, however, significant efforts are needed to reach their applications in commercial biodiesel production. [ABSTRACT FROM AUTHOR]

• A semi-conjugate model is developed to investigate the solvent removal process. • The driving force is related to the temperature increase, heat and mass transfer. • The drying time of a three-stage process is cut by about 1/5 compared to the low rate. The solvent removal process is one of the most energy intensive step in the production of lithium-ion batteries. However, the process is not well understood due to the different driving forces of the solvent liquid transport involved. Here, a semi-conjugate model that considers the effects of jet impingement on the electrode drying process is developed to investigate the solvent removal mechanism. Three different drying stages are observed. The driving force in the heating stage is due to the increase in electrode temperature. Heat transfer between the electrode and jet impingement dominates the drying process during the constant rate stage. Mass transfer in the porous electrode is the main factor affecting the drying process during the falling rate stage. Finally, the effects of process parameters such as jet temperature on the drying process are discussed. A three-stage drying process is proposed to reduce energy consumption while maintaining drying efficiency. [ABSTRACT FROM AUTHOR]

Proton exchange membrane water electrolyzer (PEMWE) is the promising approaches for the sustainable development of energy. The mass and heat transfer directly affects the cell performance at high current density, and transfer characteristics are currently unclear due to the complex reaction process. It is important to develop the detailed modeling and investigate the characteristic distribution to achieve future performance optimization. Therefore, a three-dimensional full-scale two-phase model, which couples fluid dynamics, electrochemical reaction kinetics, heat- and mass- transfers, and two-phase flow, is developed for a PEMWE. The model accuracy is validated by experimentation. Subsequently, the effects of the crucial operating and structural parameters on the cell characteristics are investigated. Furthermore, a theoretical analysis is conducted to evaluate the impacts of these parameters on energy efficiency. Results suggest that the cell performance depended strongly on the increased working temperature, the maximum current density is increased by up to 80.55 % at 2.3 V with the rise in working temperature, leading to a corresponding aggravation in gas accumulation. The flow rate of liquid water plays a positive role with regard to reducing the temperature difference of membrane and accelerating gas discharge. In addition, the channel sizes improve the cell performance within limits, wherein the increased channel width significantly contributes to reduction in mass transfer resistance of fluid between the channel and the diffusion layer. Furthermore, the energy efficiency depends on the electrochemical reaction rate the channel width and depth of 1.5 mm can effectively improve cell performance and energy efficiency, while balancing trade-off between gas accumulation and mass transfer resistance. This study offers a reference for further mechanism analysis of PEMWE, and lays a foundation for optimizing performance via characteristic distribution and energy efficiency. [Display omitted] • A full-scale two-phase mathematical model of PEMWE is developed and experimentally validated. • Characteristic distributions are obtained to explore performance via multiple perspectives. • Nonlinear effects of parameters on the performance of heat and mass transfer are discussed. • A theoretical analysis of impacts of the parameters on the energy efficiency is conducted. [ABSTRACT FROM AUTHOR]

This review investigates Double Diffusive Convection (DDC), a phenomenon where heat and solute concentration diffuse at differing rates, resulting in complex flow dynamics influenced by temperature and concentration gradients. DDC plays a crucial role in various natural and engineered systems, including oceanography, energy systems, and astrophysical contexts. This article synthesizes recent research on flow, heat, and mass transfer in DDC, emphasizing the effects of diverse flow geometries and external forces, including porous media. It examines critical parameters such as buoyancy ratio (BR), aspect ratio (AR), Prandtl (PR), Reynolds (Re), Rayleigh (Ra), and Lewis (Le) numbers, alongside the Hartmann (Ha), Soret (Sr), and Dufour (Du) numbers, highlighting their influence on velocity profiles, entropy generation, and heat/mass transfer rates quantified by Nusselt (Nu) and Sherwood (Sh) numbers. The review underscores the significant impact of geometry on DDC outcomes, demonstrating that configurations like rectangular and porous cavities enhance heat transfer efficiencies at elevated Rayleigh numbers. The introduction of nanofluids and variable porosity in porous media further optimizes thermal performance. Additionally, magnetic fields and rotation introduce complexities in flow stability and transfer efficiency, with higher Hartmann numbers leading to a transition from convection-dominated to conduction-dominated heat transfer. The interaction of thermal and solutal diffusion in porous media reveals transitions in stability, influencing flow patterns and convective currents. This comprehensive analysis highlights the vital role of geometrical configurations, fluid properties, and external forces in advancing DDC applications across diverse contexts. [ABSTRACT FROM AUTHOR]

Energy conversion based on thermodynamic cycle using zeotropic mixtures is an effective strategy for advancing global low-carbon development in the context of carbon neutrality. However, the deficiencies of existing heat transfer mixtures models and the complex condensation mechanisms of zeotropic refrigerants pose significant challenges to the size design and optimization of heat exchangers, which can directly impact the economic efficiency and operational safety of thermodynamic cycle systems. Thus, there is an urgent need for a simplified and universal correction method that incorporates mixing effects to improve prediction accuracy of conventional models. In the present study, a non-equilibrium condensation heat transfer model based on film theory was developed and validated to analyze the influence of various parameters on heat transfer degradation and heat transfer coefficients of zeotropic mixtures inside horizontal circular tubes. Through multi-factor sensitivity analysis and dimensionless method, a degradation factor characterizing the gradient contributions to heat transfer degradation was proposed. Based on the proposed factor, a simplified non-equilibrium model considering mixing effect without complex computations was developed. Using the new developed non-equilibrium model, prediction of a database containing 1813 experimental points was conducted. A deviation of 15.7 % between the predicted values and the experimental values was achieved, demonstrating remarkable predictive accuracy and significant generalizability compared to existing mixture models. Extending this corrective method to various pure substance models resulted in a significant improvement in accuracy. [ABSTRACT FROM AUTHOR]

• ·Heat and mass transfer model for multi-solute electroplating wastewater is established. • ·Reliabilities of models are verified by corresponding experimental systems. • ·Effect of main parameters on evaporation capacity of wastewater is investigated. • ·Heat and mass transfer performance of ZnCl 2 solution is worst, NiCl 2 solution is best. Electroplating wastewater is complex in composition and contains many harmful substances. Based on the single droplet heat and mass transfer method, a one-dimensional mathematical model for the evaporation separation heat and mass transfer process of multi-solute electroplating wastewater is established. In order to validate the model, the experimental system of evaporation separation tower is established, and Nusselt numbers corresponding to metal ion solutions are fitted, reliabilities of models are also verified. The maximum relative errors of mathematical models are within 10.0 %. In addition, effects of the type and concentration of metal ions and air inlet temperature on heat and mass transfer characteristics of spray separation tower are investigated. Experimental results show that when the wastewater inlet concentration is the same, the improvement effects of increasing air inlet temperature on evaporation and separation performance from high to low are ZnCl 2 , CuCl 2 , and NiCl 2 solutions. When the air inlet temperature increases from 90 °C to 130 °C, the evaporation speed of ZnCl 2 , CuCl 2 and NiCl 2 solutions increase by 90.3 %, 84.3 % and 45.7 %, respectively. When the air inlet temperature is the same, with the increase of wastewater inlet concentration, the evaporation separation performance of electroplating wastewater in descending order is ZnCl 2 , CuCl 2 , and NiCl 2 solutions. [ABSTRACT FROM AUTHOR]