Applied Thermal Engineering最新文献_第4页

Effects of heating strategies and ballistic transport on the thermal conduction in fin field-effect transistors

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126293

Chuang Zhang , Ziyang Xin , Qin Lou , Hong Liang

{"title":"Effects of heating strategies and ballistic transport on the thermal conduction in fin field-effect transistors","authors":"Chuang Zhang , Ziyang Xin , Qin Lou , Hong Liang","doi":"10.1016/j.applthermaleng.2025.126293","DOIUrl":"10.1016/j.applthermaleng.2025.126293","url":null,"abstract":"<div><div>Efficiently predicting three-dimensional temperature distributions and understanding the non-Fourier thermal conduction mechanism are of great significance for alleviating hotspot issue in fin field-effect transistors (FinFETs). Numerical solutions of the effective Fourier’s law (EFL) and the phonon Boltzmann transport equation (BTE) are two mainstream thermal engineering simulation methods in FinFETs, but continuous heating and steady-state temperature distributions are mainly considered in the previous work. Until today, effects of discontinuous heating on micro/nano scale thermal conduction is rarely studied, and the deviations between the predictions of the EFL and the phonon BTE in FinFETs are rarely compared, either. To answer these questions, three different heating strategies are considered including ‘Continuous’, ‘Intermittent’ and ‘Alternating’ heating, and the heat conduction processes in FinFETs are simulated by both the phonon BTE and EFL. Numerical results show that different heating strategies have great influence on the peak temperature rise and transient thermal dissipation process. Compared to ‘Intermittent’ or ‘Continuous’ heating, the temperature variance of ‘Alternating’ heating is smaller. The peak temperature rise of ‘Alternating’ heating is <span><math><mrow><mn>28</mn><mtext>%</mtext><mo>−</mo><mn>43</mn><mo>.</mo><mn>5</mn><mtext>%</mtext></mrow></math></span> lower than that of ‘Continuous’ heating in FinFETs. The silicon dioxide insulation layer reduces the thermal shock on the bottom substrate material although it raised the overall temperature in the fin area. It is not easy to accurately capture the heat conduction in FinFETs by the EFL, especially near the nanoscale hotspot and corner areas where ballistic phonon transport dominates and the temperature diffusion is no longer valid.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126293"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transient model and performance evaluation of a polygonal automobile exhaust thermoelectric generator under different driving cycles

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126348

Rui Quan, Xuerong Li, Yulong Zhou, Hang Wan, Yufang Chang

{"title":"Transient model and performance evaluation of a polygonal automobile exhaust thermoelectric generator under different driving cycles","authors":"Rui Quan, Xuerong Li, Yulong Zhou, Hang Wan, Yufang Chang","doi":"10.1016/j.applthermaleng.2025.126348","DOIUrl":"10.1016/j.applthermaleng.2025.126348","url":null,"abstract":"<div><div>Considering the steady-state model is difficult to accurately evaluate the transient performance of the automobile exhaust thermoelectric generator (AETEG) system under practical conditions, an octagonal AETEG system embedded with sickle-shaped fins was designed in this work, and a transient computational fluid dynamics (CFD) model was established to precisely assess the dynamic fluid-thermal coupling characteristic under four driving cycles of China Light-duty Vehicle Test Cycle (CLTC), Highway Fuel Economy Test (HWFET), New European Driving Cycle (NEDC) and Urban Dynamometer Driving Schedule (UDDS). Moreover, the dynamic voltage, power, and conversion efficiency were numerically calculated with a theoretical analytical model based on the transient fluid and thermal distribution. Results indicate that the predicted voltage and power errors between simulation data and experimental results are 4.25 % and 4.73 %, respectively, verifying the feasibility of the constructed transient numerical model. Additionally, both the transient output voltage and power are proportional to exhaust temperature, and the hysteresis effect in the heat transfer affects AETEG’s output performance smoothness and leads to its peak conversion efficiency when the heat absorption plummets. The AETEG system has the best average transient output performance under the HEFET driving cycle due to the continuous high-temperature exhaust flow, and the average transient power and conversion efficiency approach 81.11 W and 2.1 %, respectively. Under the CLTC driving cycle, the AETEG system reaches the best maximum voltage, power, and conversion efficiency of 170.02 V, 144.54 W, and 7.47 %, respectively. This study provides theoretical guidance for transient performance analysis and optimization of AETEG systems during in-vehicle applications.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126348"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Joint optimization of leg configuration and fin structure in a two-stage segmented thermoelectric generator for enhanced 3E performance

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126354

Wenlong Yang , Chenchen Jin , Wenchao Zhu , Peipei Meng , Wei Lin , Hao Li , Changjun Xie

{"title":"Joint optimization of leg configuration and fin structure in a two-stage segmented thermoelectric generator for enhanced 3E performance","authors":"Wenlong Yang , Chenchen Jin , Wenchao Zhu , Peipei Meng , Wei Lin , Hao Li , Changjun Xie","doi":"10.1016/j.applthermaleng.2025.126354","DOIUrl":"10.1016/j.applthermaleng.2025.126354","url":null,"abstract":"<div><div>Existing research typically optimizes either the thermoelectric leg configuration or the fin structure independently, often neglecting the potential interactions between the two. This study proposes a novel two-stage segmented thermoelectric generator, examining the interplay between thermoelectric legs and fin structure and their impact on energy, exergy, and economic (3E) performance. Using the Taguchi method and Grey Relational Analysis, a joint optimization of thermoelectric legs and fin structure was conducted. The results reveal a significant interaction effect between the leg structure and fin thickness. The optimal leg structure is contingent on the fin thickness, and vice versa. When the area ratio between the upper and lower leg sections is 0.5, the optimal fin thickness is 1 mm; when the area ratio increases to 1, the optimal fin thickness decreases to 0.5 mm. However, the optimal fin spacing is not influenced by the leg structure. The optimized two-stage segmented thermoelectric generator exhibits superior 3E performance, with net power, exergy efficiency, and levelized energy cost reaching 19.36 W, 12.14 %, and 25.5 W/$, respectively. These values represent improvements of 32.3 %, 34.4 %, and 100.7 % over conventional two-stage thermoelectric generators. This study provides crucial design guidance for the joint optimization of fin and thermoelectric semiconductor structures.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126354"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation on the operating boundaries and performance of sCO2 closed-Brayton cycles for hypersonic vehicles

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126346

Jingqi Li , Yulong Li , Xingjian Li

{"title":"Evaluation on the operating boundaries and performance of sCO2 closed-Brayton cycles for hypersonic vehicles","authors":"Jingqi Li , Yulong Li , Xingjian Li","doi":"10.1016/j.applthermaleng.2025.126346","DOIUrl":"10.1016/j.applthermaleng.2025.126346","url":null,"abstract":"<div><div>Supercritical CO<sub>2</sub> closed Brayton cycles have demonstrated significant advantages in thermal management systems for hypersonic vehicles, that require thermal protection and power generation. Due to the limitations in temperature and temperature difference, the limited cold source provided by the propellant has limited the operating range of SCBCs. This investigation examines the operating boundaries and performance characteristics of various SCBC configurations in the presence of these limitations. A zero-dimensional thermodynamic analysis model in conjunction with a quasi-one-dimensional cooling channel model is appropriately established to determine the operating boundaries of three typical SCBC configurations, including simple layout, recuperative layout, and recompression layout. The influences of compressor inlet temperature (<em>T</em><sub>0</sub>), inlet pressure (<em>p</em><sub>0</sub>), maximum cycle pressure (<em>p</em><sub>1</sub>) are methodically analyzed, along with the effects of recuperator effectiveness and split ratio. First, the upper and lower boundaries of the operating range are defined, and the obtained results reveal that lower <em>T</em><sub>0</sub> leads to a reduction of the operating range in all layouts, while <em>p</em><sub>0</sub> exhibits a similar impact on layouts with recuperators. An optimal combination of recuperate effectiveness and <em>T</em><sub>0</sub> that maximizes the net work output is also identified in the RL configuration, however, no optimal split ratio is detected in the RCL configuration. The layouts are then suitably optimized and compared under the concept of maintaining a certain level of operational flexibility. The RL configuration achieved the highest cycle net work of 40.61 kW in the presence of a flow margin of ±5 %, making it the optimal layout for onboard supercritical CO<sub>2</sub> closed Brayton cycles systems with a finite cold source.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"272 ","pages":"Article 126346"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel method of in-situ temperature distribution measurement of solid oxide fuel cell stack

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126355

Xingyu Xiong , Bintao Zheng , Yunfei Wu , Liang Hu , Xin Wu , Suping Peng

{"title":"A novel method of in-situ temperature distribution measurement of solid oxide fuel cell stack","authors":"Xingyu Xiong , Bintao Zheng , Yunfei Wu , Liang Hu , Xin Wu , Suping Peng","doi":"10.1016/j.applthermaleng.2025.126355","DOIUrl":"10.1016/j.applthermaleng.2025.126355","url":null,"abstract":"<div><div>A novel method for measuring the in-situ temperature of the Solid Oxide Fuel Cell (SOFC) stack is developed. Multiple optical silica fibers with a 0.4 mm diameter were integrated into a 3 × 3 array which was plugged into a 1 kW stack. The in-situ temperature of the stack with different loads in steady-states and dynamics operating conditions was tested within a furnace heated up to 750 °C. By moving the fiber array using a three-axis manipulator, the temperature distributions along the cathode flow channels were scanned and the measurement resolution was set to 1 mm. For the current load with 10 A, 20 A and 30 A in a steady-state, the experimental results show a clear trend of higher temperature on outlet and top of the stack in steady-state. The maximum temperature differences inside the stack were more than 44 °C for 30 A. During the processes of the start-up, current linearly increased from 0A to 10 A, 20 A and 30 A individually with a fixed slope of 2.5 A/min and the current was maintained for 20 min, the maximum temperature of the stack raised to 766 °C, 783 °C and 805 °C, respectively. Moreover, the dynamic responses of the temperature with fluctuating inputs such as a rapid step loading and unloading test from 0 A to 30 A and 30 A to 0 A in 4 min recorded that the temperature change rate inside the stack was within 1 °C/min, which shows a capability of quickly power adjusting of SOFC.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126355"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental and numerical study on the thermal and hydraulic characteristics of an improved PCHE with high-viscosity fluid

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126345

Jie Wen , Huifang Ma , Guoqiang Xu , Bensi Dong , Zhiwei Liu , Laihe Zhuang

{"title":"Experimental and numerical study on the thermal and hydraulic characteristics of an improved PCHE with high-viscosity fluid","authors":"Jie Wen , Huifang Ma , Guoqiang Xu , Bensi Dong , Zhiwei Liu , Laihe Zhuang","doi":"10.1016/j.applthermaleng.2025.126345","DOIUrl":"10.1016/j.applthermaleng.2025.126345","url":null,"abstract":"<div><div>The increasing heat load in the lubricating oil system imposes higher requirements on the heat dissipation capacity of the fuel–oil heat exchanger. A Printed Circuit Heat Exchanger (PCHE) has emerged as a promising candidate to substitute for the traditional shell-tube heat exchanger due to its exceptional thermal efficiency and compact design. In this study, a new PCHE configuration is designed which staggered discontinuous fins with modified airfoil fins and cylindrical spoiler columns located at the inlet and outlet to avoid the high-velocity and negative pressure gradient areas while improving strength and flow field uniformity. Experimental results show that the thermal–hydraulic performance on the oil side is significantly influenced by the inlet temperature because the viscosity varies more sharply with temperature at the same Reynolds number, unlike the fuel side. Further numerical investigations reveal larger regions of high heat flux, high temperature, and high velocity on the oil side at lower inlet temperatures, which lead to increased heat conduction and more effective heat transfer in laminar flow. Additionally, the correlations for the Nusselt number (<em>Nu</em>) and the friction coefficient of fuel and oil in modified airfoil fins PCHE have been developed. Under the laminar flow, the modified airfoil fins PCHE exhibits superior heat transfer, with the <em>Nu</em> being 1.70 times higher than that of airfoil fins (<em>S</em><sub>1</sub> = 6.0 mm), 2.10 times higher than that of zigzag channels, 2.83 times higher than that of airfoil fins (<em>S</em><sub>1</sub> = 2.4 mm), and 4.70 times higher than that of straight channels at <em>Re</em> = 396.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126345"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Coaxial geothermal wellbore thermoelectric power generation system: design, experimentation, and performance analysis

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126349

Lei Wang , Kewen Li , Yuhao Zhu , Wenjie Hao , Fawang Zhang , Yanxin Shi , Yiwen Wang , Shuai Yang

{"title":"Coaxial geothermal wellbore thermoelectric power generation system: design, experimentation, and performance analysis","authors":"Lei Wang , Kewen Li , Yuhao Zhu , Wenjie Hao , Fawang Zhang , Yanxin Shi , Yiwen Wang , Shuai Yang","doi":"10.1016/j.applthermaleng.2025.126349","DOIUrl":"10.1016/j.applthermaleng.2025.126349","url":null,"abstract":"<div><div>Thermoelectric generators have demonstrated significant potential for geothermal power generation, with extensive research validating their technical and economic feasibility. While prior studies have primarily focused on surface-based thermoelectric generator systems, downhole thermoelectric power generation remains largely unexplored, with research limited to numerical simulations. To address this gap, this study proposes a novel experimental apparatus for power generation in a coaxial geothermal wellbore. A 1-meter-long wellbore thermoelectric generation system was designed and developed to analyze the influence of temperature differentials and flow rates on power generation efficiency. Experiments were conducted using controlled hot and cold water injection to simulate geothermal wellbore conditions. Results indicate that under a temperature difference of 70 °C, with a cold flow rate of 288 L/h and a hot flow rate of 648 L/h, the system achieves a maximum power output of 26.7 W. The power output exhibits an exponential increase with temperature difference, while optimizing both hot and cold flow rates further enhances energy conversion efficiency. To extend the analysis to field-scale applications, a coaxial closed-loop geothermal wellbore model was established. Numerical simulations predict that a 1000-meter-long wellbore thermoelectric generation system operating at a temperature difference of 200 °C can generate 534.6 kW of power with a conversion efficiency of 8.5 %. These findings provide critical insights into the thermal transport mechanisms and performance optimization of downhole thermoelectric power generation, bridging the gap between theoretical analysis and practical application. This research lays the foundation for future large-scale deployment of thermoelectric generators in geothermal energy utilization.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126349"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparative analysis between concentration difference energy storage method and super-capacitor energy storage method for absorption air-conditioning system

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126343

Zhuohao He, Feng Cheng, Xiuwei Li

{"title":"Comparative analysis between concentration difference energy storage method and super-capacitor energy storage method for absorption air-conditioning system","authors":"Zhuohao He, Feng Cheng, Xiuwei Li","doi":"10.1016/j.applthermaleng.2025.126343","DOIUrl":"10.1016/j.applthermaleng.2025.126343","url":null,"abstract":"<div><div>Increasing the proportion of renewable energy in the energy resource structure helps promote energy conservation and emission reduction worldwide. In the field of building energy conservation, the use of solar energy to drive green air-conditioning systems is a hot research topic. One representative is the solar-driven LiBr-H<sub>2</sub>O absorption cooling system that exerts no negative influence on environment. Due to the intermittency of solar energy, the solar-driven system cannot operate continuously and stably. The analysis has been made based on two kinds of solar energy driven system that are the traditional absorption cooling system and capacitive deionization (CDI) absorption cooling system. Different energy storage solutions have been proposed for absorption systems and compared in terms of energy storage density (ESD) and efficiency (ESE). The CDI unit in CDI system works similarly to a double-layer capacitor, and the ions adsorbed on the electrodes can be used to concentrate the absorbent solution in the system to obtain the refrigeration potential. Therefore, it is a novel perspective to consider it as a cooling energy storage device. The results show that the main advantage of the supercapacitor energy storage (SCES) method over the concentration difference energy storage (CDES) method are the consumption of only one-tenth of the energy storage solution and high ESD, leading to lower costs. However, the low efficiency of photovoltaic (PV) cells limits its energy storage performance. A combined solar thermal and photovoltaic drive system utilizing waste heat from PV cells is an effective solution. With a coefficient of performance (COP’) between 0.56 and 0.59 on the design day and an ESE of up to 0.586, the system exhibits the strongest solar energy utilization and storage capability.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126343"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical and experimental study of an integrated thermoelectric active cooling system for ultra-high temperature downhole electronics

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126341

Chao Deng , Fulong Wei , Jiale Peng , Siqi Ding , Jinlong Ma , Xiaobing Luo

{"title":"Numerical and experimental study of an integrated thermoelectric active cooling system for ultra-high temperature downhole electronics","authors":"Chao Deng , Fulong Wei , Jiale Peng , Siqi Ding , Jinlong Ma , Xiaobing Luo","doi":"10.1016/j.applthermaleng.2025.126341","DOIUrl":"10.1016/j.applthermaleng.2025.126341","url":null,"abstract":"<div><div>The external polar plate circuit is a critical component of the scanning imaging logging tool which must work in ultra-high temperature environment, and thus effective thermal management is imperative. However, the limited internal space and the requirement for stretching functionality present great challenges. In this study, a novel integrated thermoelectric cooling system (TCS) is proposed to cool the external circuit in an environment reaching 230 °C, a condition far more extreme than those addressed in previous studies. Specifically, the design incorporates dual thermoelectric coolers integrated at the top and bottom of the circuit to establish bi-directional heat dissipation pathways, while insulating the surroundings to minimize the heat leakage from environment. The cooling performance of the proposed TCS was evaluated through both experiments and numerical simulations. The results indicate that the system can maintain the temperature of a 3 W heat source at 190.2 °C in a 230 °C environment. The numerical results from COMSOL simulations align well with experimental data, with a temperature error of less than 2.6 °C. It suggests that the overall coefficient of performance (COP) of the proposed TCS is 0.097 and an ambient heat leakage is 0.42 W. The proposed TCS demonstrates excellent temperature control performance, long-term stable operation capability, and broad application prospects.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126341"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Scaling transient heat transfer in impinging flames under compression-ignition engine-like conditions

IF 6.1 2区工程技术

Applied Thermal Engineering Pub Date : 2025-03-28 DOI: 10.1016/j.applthermaleng.2025.126352

Jiale Cao , Xinyi Zhou , Xingyu Xu , Run Chen , Shiyan Li , Sanghoon Kook , Tie Li

{"title":"Scaling transient heat transfer in impinging flames under compression-ignition engine-like conditions","authors":"Jiale Cao , Xinyi Zhou , Xingyu Xu , Run Chen , Shiyan Li , Sanghoon Kook , Tie Li","doi":"10.1016/j.applthermaleng.2025.126352","DOIUrl":"10.1016/j.applthermaleng.2025.126352","url":null,"abstract":"<div><div>Understanding transient heat transfer similarity in impinging flames is crucial for scaled experiments. This study investigates transient heat transfer similarity for impinging flames under conditions simulating small- and large-bore compression-ignition (CI) engines. Experiments were conducted in a constant volume vessel using injectors with a geometry similarity ratio of 0.72. Flame luminosity and temperature were captured using two-color pyrometry, while fast-response thermocouples measured local and spatial-averaged transient heat transfer. Three similarity rules (injection pressure, engine speed, and lift-off length) were evaluated, and a novel cumulative injection velocity parameter was introduced. Results indicate that similarity rules effectively predict flame development parameters, such as tip penetration, flame height, and radius under scaled engine-like conditions. Among the evaluated similarity rules, the engine speed similarity rule (S Rule) provided the best predictive accuracy for transient heat transfer. The new characteristic velocity parameter significantly improved accuracy in predicting transient heat transfer. The findings demonstrate the effectiveness of the new cumulative injection velocity parameter in transient heat transfer calculations, providing valuable guidance for scaling methodologies in CI engine design.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"271 ","pages":"Article 126352"},"PeriodicalIF":6.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0