Peng Guan^*, Ming-Ran Li, Si-Bo-Wen Wang

Frontiers in Heat and Mass Transfer, Vol.24, No.4, 2026, DOI:10.32604/fhmt.2026.082595 - 31 August 2026

Abstract This paper develops a thermomechanical optimization method for turbo guide vane (TGV) weight reduction under restrictive conditions and highly sensitive variables. The proposed method integrates a flow-thermo-structural model, orthogonal experimental design (OED), and an optimization framework based on response surface methodology (RSM) and a genetic algorithm (GA). To address both the plastic limit and temperature distribution of the TGV, a new parameter termed the stress ratio is introduced as a constraint during optimization. Six highly sensitive variables were selected from ten cooling channel diameters using OED. Simulation results based on the thermal-fluid coupling model were… More >

Anxiang Shen¹, Xinxin Ren², Tao Wang¹, Jianqiu Zhou^1,2,*

Frontiers in Heat and Mass Transfer, Vol.24, No.4, 2026, DOI:10.32604/fhmt.2026.082573 - 31 August 2026

Abstract To address the growing number of variable-composition ejector refrigeration cycles, this study proposes analyzing the matching performance between working fluids and cycles through 3D (Temperature-Entropy-Mass fraction) Thermodynamic Diagrams. The ejector refrigeration cycle is decoupled into a driving module and a refrigeration module, and a theoretical upper-bound model (COP_limiting) that depends only on working-fluid properties is derived from the T-s diagram. Graph-theoretic analysis yields an explicit relation between COP_limiting and fluid-specific parameters such as Δs_b-b^′/Δs_a-b^′ and Δs_e-e^′/Δs_d-e^′. Definition of k₁ (ΔT_4–7/Δs_e-e^′) and k₂ (ΔT_3–4/Δs_b-b^′) reveals that wet fluids favour the refrigeration module, whereas dry fluids favour the driving module. The influence… More >

Yang Long¹, Bowei Xie^2,*, Linkang Wang¹, Mu Du^2,*

Frontiers in Heat and Mass Transfer, Vol.24, No.4, 2026, DOI:10.32604/fhmt.2026.082479 - 31 August 2026

Abstract This work proposes a simple multilayer smart coating with wide-band response characteristics based on In₃SbTe₂ (IST) phase change material, which can achieve significant and gradient dynamic regulation of infrared emittance while ensuring a low solar absorptance. The spectral directional emittance and absorptance characteristics are calculated by the rigorous coupled wave analysis method, and the genetic algorithm is used for global optimization design of the structural parameters. The simulated results show that the smart coating can maintain excellent optical performance with a solar absorptance lower than 0.325, while achieving a significant regulation range of infrared emittance over… More >

Jiaxi Shen, Zhiyun Wang^*

Frontiers in Heat and Mass Transfer, Vol.24, No.4, 2026, DOI:10.32604/fhmt.2026.081961 - 31 August 2026

Abstract This study focuses on the modeling and performance prediction of the condensation heat transfer process within an ACC system of a 100 MW unit. A one-dimensional physical model was established, and solutions were obtained using an iterative numerical method based on the first law of thermodynamics. The core of this work involves precise modifications to the heat transfer coefficient. Firstly, the Shah correlation for horizontal tube condensation was improved by incorporating the air mass fraction and the Jakob number to quantify the impact of non-condensable gases. Secondly, to assess the influence of the pipe installation More >

Guang Wen¹, Wenling Liao^1,2,*, Shuaimei Lian¹, Pingping Liu^1,*

Frontiers in Heat and Mass Transfer, Vol.24, No.4, 2026, DOI:10.32604/fhmt.2026.081270 - 31 August 2026

Abstract In this work, FLUENT is used to systematically investigate the effects of two key factors on the hydrothermal performance and entropy generation within a mass flow rate range of 0.3–1.1 g/s: (1) the coupling modes between grooves (simple and composite) and microchannels (straight, convergent, and divergent), and (2) the cross-sectional shape of composite grooves. Results show that, compared with simple grooves, composite grooves induce stronger spiral fluid disturbances between the mainstream and near-wall zones, enhancing direct fluid impingement on groove walls and thus improving the cooling effect on the microchannel. Among the configurations, the coupling More >

Wensheng Li¹, Zeyang Zhang¹, Xinjie Chai², Facheng Qiu^1,*

Frontiers in Heat and Mass Transfer, Vol.24, No.4, 2026, DOI:10.32604/fhmt.2026.080472 - 31 August 2026

Abstract Hydrodynamic jet technologies have emerged as a promising approach for advanced wastewater treatment, offering engineering advantages through operational efficiency and system simplicity. As a critical review, this work examines three major hydrodynamic approaches—atomized jets, cavitation jets, and pulsed-jet systems—and analyzes their degradation mechanisms and practical applications in pollutant abatement. By systematically evaluating current research trends, this review elucidates the synergistic interplay between hydrodynamic effects, including turbulent shear, microbubble implosion, and reactive radical generation, and contaminant-decomposition pathways. Quantitative evidence from the reviewed literature further reveals significant performance enhancements achieved by these technologies. Optimized cavitating jets (e.g.,… More > Graphic Abstract

Zeliang Liang^1,2, Jia Tan^1,*, Jiachao She², Fengnian Wang², Yi Wang², Donghao Li³, Rugang Duan³, Haotian Chu⁴

Frontiers in Heat and Mass Transfer, Vol.24, No.4, 2026, DOI:10.32604/fhmt.2026.078050 - 31 August 2026

Abstract Significant wettability differences between proppants and coal matrices in deep coal reservoirs limit gas–water mass transfer, a key factor for coalbed methane recovery. This study develops a hybrid wettability fracture model using in-situ data, coupling Navier–Stokes equations with a phase-field method to simulate multi-scale gas–water flow. A random wettability mapping technique captures spatial heterogeneity. The critical capillary number (Ca)-balancing capillary and viscous forces-serves as the key threshold governing flow pathways. At low Ca, capillary forces dominate, causing liquid film aggregation and gas blockage; at high Ca, viscous forces break films and open pathways. Wettability gradients drive asynchronous More >

Yan Xiao¹, Ruoyi Xie¹, Song Gao², Jinhui Yang¹, Luyao Liang¹, Shaozhi Zhang^1,*

Frontiers in Heat and Mass Transfer, Vol.24, No.4, 2026, DOI:10.32604/fhmt.2026.077396 - 31 August 2026

Abstract When redeploying servers or installing new racks within an existing data center, assessing the local rack-level thermal environment is crucial to ensure target areas meet stringent cooling requirements. To date, limited research has addressed this specific issue. In this study, experimental measurements and CFD simulations were conducted to evaluate the local thermal environment of an operational data center. The Index of Mixing (IOM) was selected as the primary metric for thermal evaluation. To closely mimic real-world conditions, a 2U server simulator featuring adjustable air volume and heating power was constructed. Experimental results indicated that the… More >

Perihan Hazel Kaya^1,*, Coşkun Kuş², Mustafa Çoklu³, Mustafa Göktuğ Kaya⁴

Energy Engineering, Vol.123, No.10, 2026, DOI:10.32604/ee.2026.084804 - 30 August 2026

Abstract This study examines the relationship between energy consumption, renewable energy supply, and economic growth in BRICS countries over the period 2000–2023 within the framework of panel data analysis. In the analysis, economic growth is represented by gross domestic product, while total energy consumption and renewable energy supply are used as the main energy-related variables. The study contributes to the literature by evaluating the energy-growth nexus together with both total energy use and renewable energy dynamics in BRICS economies. Since BRICS countries may be affected by common global shocks, cross-sectional dependence is considered in the empirical… More >

Hanna Hrinchenko^1,*, Nataliia Antonenko¹, Halyna Kryshtal², Alla Krysak³, Svitlana Bilous-Sergieieva⁴, Yana Medvedovska⁵

Energy Engineering, Vol.123, No.10, 2026, DOI:10.32604/ee.2026.084705 - 30 August 2026

Abstract The transition towards long-term operation and increasing safety standards for nuclear power plant (NPP) units necessitates a fundamental shift from isolated technical monitoring to integrated, risk-oriented performance evaluation. The increasing complexity, safety requirements, and extended operation of nuclear power plant (NPP) units necessitate advanced approaches for assessing their functional performance. This study aims to develop a risk-oriented qualimetric (integrated multi-criteria quality assessment) methodology for comprehensive evaluation of NPP unit operation, integrating both quantitative and qualitative indicators while accounting for their interdependencies. This study develops a novel risk-oriented qualimetric methodology for the holistic assessment of NPP… More > Graphic Abstract