Hao Zhu^1,2, Xi Chen^1,2,*, Pengcheng Qu^1,2, Yifan Zhu^1,2, Haoyi Wang^1,2, Yingxia Qi^1,2

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.076127 - 28 February 2026

Abstract Pulse tube cryocoolers are widely employed in cryogenic systems, where gas contamination has become a critical factor limiting both performance and service life. To further investigate the condensation behavior of contaminants, this study develops a two-dimensional axisymmetric model of a linear-type cryocooler to simulate the transport and deposition processes of trace CO₂, evaluating the impact of contamination on system pressure drop under various operating conditions. Results indicate that CO₂ diffusion is primarily driven by concentration gradients. The CO₂ deposition rate increases markedly at low temperatures and high concentrations, with over 90% of deposition occurring in the cold-end… More >

M. A. Vega Navarrete^1,*, P. J. Argumedo Teuffer¹, C. M. Rodríguez Román¹, L. E. Marrón Ramírez², E. A. Islas Narvaez¹

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.076095 - 28 February 2026

Abstract This article presents an adaptive intelligent control strategy applied to a lumped-parameter evaporator model, i.e., a simplified dynamic representation treating the evaporator as a single thermal node with uniform temperature distribution, suitable for control design due to its balance between physical fidelity and computational simplicity. The controller uses a wavelet-based neural proportional, integral, derivative (PID) controller with IIR filtering (infinite impulse response). The dynamic model captures the essential heat and mass transfer phenomena through a nonlinear energy balance, where the cooling capacity “Qevap” is expressed as a non-linear function of the compressor frequency and the… More >

Yumeng Li, Fuyong Su^*

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.076007 - 28 February 2026

Abstract Based on the Fluent numerical simulation method, this study systematically analyzed the structural parameters of the spiral tube heat exchanger and the influence of the external baffle on its heat transfer performance. The results show that when the equivalent diameter of the spiral tube increased from 16.68 to 21.23 mm, its surface heat transfer coefficient decreased from 22,040 to 17,230 W/m²·K, and the outlet air temperature dropped from 822.3 to 807.3 K. However, the pressure loss decreased from 2.692 to 0.958 kPa. which reveals the contradiction between the heat transfer efficiency and the flow resistance. By More > Graphic Abstract

Wei Dong¹, Xuqing Feng², Taoxiang Mei², Xiang Li², Zhenzong He^2,3,*

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.075846 - 28 February 2026

Abstract The proton exchange membrane fuel cell (PEMFC) and the hydrogen hybrid power system are studied by the fuzzy-PID (FPID) control method and the fuzzy-PID control method by Artificial Bee Colony algorithm (ABC-FPID), respectively. The results reveal that compared with the FPID control method, the temperature overshoot of the PEMFC stack under the ABC-FPID control method is decreased by 0.6%. Moreover, the circulating water flow rate within the full operating envelope (about 3 min) is reduced by 19.46 L, which means the ABC-FPID control method is more effective in regulating the stack temperature. Then, the ABC-FPID… More >

Lei Xing¹, Haonan Huang², Mingyang Sun², Dongyue Jiang^2,*, Qiang He^1,*

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.075774 - 28 February 2026

Abstract In response to the actual demands of the energy storage type organic Rankine power generation cycle, this study proposes a new type of jacketed shell and tube heat exchanger with integrated cold storage and heat exchange. N-tedecane is selected as the phase change material for cold storage, low-temperature water as the cold source, and R134a as the heat source. The phase change material for cold storage is filled inside the jacket tube of the heat exchanger. Cold fluid is introduced into the inner tube to cause the phase change material to condense and store cold.… More >

Taher Maatallah^1,*, Nagmeldeen A. M. Hassanain¹, Gaydaa Al Zohbi², Farooq Saeed¹, Muhammad Saleem¹, Nassir Hariri¹, Mohamed Elsharawy³, Tapas Kumar Mallick^1,4, Fahad Gallab Al-Amri¹

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.075763 - 28 February 2026

Abstract High-concentration photovoltaic (HCPV) systems present significant thermal management challenges due to the intense heat fluxes generated under concentrated solar irradiation, especially in arid environments. Effective heat dissipation is critical to prevent performance degradation and structural failure. This study investigates the thermal performance and design optimization of an enhanced HCPV module, integrating numerical, analytical, and experimental methods. A coupled optical-thermal-electrical model was developed to simulate ray tracing, heat transfer, and temperature-dependent electrical behaviour, with predictions validated under real-world desert conditions. Compared to a baseline commercial module operating at 106°C, the optimized design achieved a peak temperature More >

Luling Li¹, Minghui Li², Zhengxiang Xu², Haofeng Lin², Xuemei Lang², Peiming Li¹, Hengrong Zhang^1,*, Dongxu Ji^3,*, Jian Liu¹, Jianhui Liu¹, Guang Yang¹, Shuanshi Fan^2,*

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.075692 - 28 February 2026

Abstract This study addresses the energy-intensive challenge of small-scale biogas upgrading by optimizing a chemical absorption process employing methyl diethanolamine (MDEA). Focusing on a typical distributed application of 300 Nm³/d, we developed an integrated simulation-optimization framework using Aspen HYSYS 14.0 to systematically evaluate the effects of critical operating parameters—absorption pressure, MDEA concentration, flow rate, temperature, number of trays, and reboiler duty—on methane purity and energy consumption. The key finding is the identification of an optimal parameter set: absorption pressure of 1200 kPa, MDEA concentration of 20 mol%, lean flow rate of 2.5 kmol/h, temperature of 298.15 K,… More >

Jin Huang¹, Zihao Tang¹, Tingting Wu¹, Hualiang Li², Yanxin Hu^1,*

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.075643 - 28 February 2026

Abstract In order to explore the effects of CaO, lignite dust and sawdust on the drying characteristics of municipal sludge at different concentrations, a three-factor three-level regression experiment was carried out based on the results of thermogravimetric experiment and single factor experiment. By fitting three common mathematical models, the Page model with the highest fitting degree was selected to determine the most suitable mathematical model to describe the municipal sludge drying process. In addition, the Box-Behnken design principle in the response surface method was used to analyze the interaction of three factors on the drying characteristics… More >

Geqiang Li^1,2, Kai Wang¹, Juntao Liu³, Zhengyang Han^1,2, Shuai Wang^1,2,*, Donglin Li^1,2

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2025.075249 - 28 February 2026

Abstract To explore the distribution law of the temperature field in the motor pump and the influence of the fan-shaped DC channel with spoiler in the pump housing on its heat dissipation performance. This study takes the arc-gear type hydraulic motor pump as the research object. In COMSOL, a coupled heat transfer simulation model of the motor pump’s fluid-solid coupling is established, and the internal temperature field characteristics are analyzed. To improve the heat dissipation effect of the motor pump, it is proposed to arrange spoiler in the fan-shaped DC channel of the pump housing to… More >

Anandhi C.¹, Narsu Sivakumar^1,*, Revathi Devi M.²

Frontiers in Heat and Mass Transfer, Vol.24, No.1, 2026, DOI:10.32604/fhmt.2026.075232 - 28 February 2026

Abstract This work explores a Magnetohydrodynamic (MHD) flow in a triangular cavity with a thermally insulated baffle. Enclosure’s inclined wall is hotter, whereas the vertical border is adiabatic and the bottom is cooler. The study aims to clarify how geometric changes affect thermal performance and offers new perspectives on how to improve heat dissipation mechanisms. A COMSOL Multiphysics version 6.2 has been used to solve numerical solutions. Streamlines and thermal distributions are examined systematically in order to understand how the unique geometry and baffle size of triangular cavities can influence the fluid flow. This influence can More >