Journal of Heat Transfer-transactions of The Asme最新文献_第2页

Analysis of Multilayer Cylindrical Thermal Conduction with a Time-Varying Convective Boundary Condition 具有时变对流边界条件的多层圆柱热传导分析

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063961

Long Zhou, Mohammad Parhizi, Ankur Jain

{"title":"Analysis of Multilayer Cylindrical Thermal Conduction with a Time-Varying Convective Boundary Condition","authors":"Long Zhou, Mohammad Parhizi, Ankur Jain","doi":"10.1115/1.4063961","DOIUrl":"https://doi.org/10.1115/1.4063961","url":null,"abstract":"Abstract Heat transfer in a multilayer body plays a key role in design and optimization of several engineering systems. While the analysis of simple multilayer problems is quite straightforward, realistic scenarios such as time-dependent boundary conditions result in significant complications in analysis. This work presents thermal analysis of a heat-generating multilayer cylinder with time-varying convective heat transfer at the boundary. Such a scenario may occur in applications such as nuclear reactors, jet impingement cooling, turbine blade heat transfer, as well as casting and related manufacturing processes. Analysis is presented for both annular and solid cylinders. A derivation for the temperature distribution is carried out, using a shifting function to split the time-dependent boundary condition into two parts, followed by appropriate mathematical substitution. For particular special cases, the analytical results derived here are shown to reduce exactly to results from past work. Good agreement of the theoretical results with numerical simulations is also demonstrated. Thermal response to a various realistic time-dependent boundary conditions is analyzed. This work may enable the theoretical design and optimization of realistic multilayer problems, and may serve as a design tool for optimization of engineering systems where multilayer thermal conduction plays a key role.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"23 18","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135973280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 Investigation of Flow Boiling in Additive Manufactured Foam Structures With Vapor Pathways 含蒸汽通道的添加剂泡沫结构流动沸腾的实验与数值研究

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063960

Justin Broughton, Emanuel Torres, Akshith Narayanan, Yogendra Joshi

{"title":"Experimental and Numerical Investigation of Flow Boiling in Additive Manufactured Foam Structures With Vapor Pathways","authors":"Justin Broughton, Emanuel Torres, Akshith Narayanan, Yogendra Joshi","doi":"10.1115/1.4063960","DOIUrl":"https://doi.org/10.1115/1.4063960","url":null,"abstract":"Abstract The unique properties of metal foams make them potential candidates for a range of applications, including microsystem thermal management. Using additive manufacturing to create foam-type structures can improve upon prior thermal solutions by eliminating thermal interface materials and allowing for customization/local control of parameters. In the present investigation, flow boiling in additive manufactured metal foams is investigated both experimentally and numerically. Two test samples, one with uniform structure and the other with pathways for vapor removal, are compared both experimentally and numerically. A conjugate computational fluid dynamics and heat transfer (CFD-HT) model utilizing a three-dimensional volume of fluid (VOF) model with accompanying evaporation/condensation model provided in-depth visualization of the boiling flow phenomena. The experiments generated the thermohydraulic performance over a range of heat fluxes, demonstrating that the sample incorporating dedicated vapor pathways performed better in both pressure and heat transfer performance metrics compared to the uniform foam. Additionally, negative system-level effects (i.e., hydraulic oscillations) were shown to be abated using the vapor removal structures. The numerical model yielded further insight into the factors contributing to the improved performance. Results indicated the pathways functioned as vapor removal channels, allowing the generated vapor to vent from the foam structure into the lanes. Further computational investigations demonstrated changes in flow regimes, where the addition of vapor channels caused the flow to change from churn to annular. Bubble behavior unique to the vapor pathway structure was studied, showing stagnant regions that eject vapor into the channel.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"23 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135973286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Study on Thermo-Hydraulic Performance and Correlation Development of The Interrupted Flying-Wing Fins 断续式飞翼翅片热液性能研究及相关发展

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063964

Xin Qi, Ling Wang, Teng Qing, Peng Yang, ying-wen Liu

{"title":"Study on Thermo-Hydraulic Performance and Correlation Development of The Interrupted Flying-Wing Fins","authors":"Xin Qi, Ling Wang, Teng Qing, Peng Yang, ying-wen Liu","doi":"10.1115/1.4063964","DOIUrl":"https://doi.org/10.1115/1.4063964","url":null,"abstract":"Abstract This paper focuses on investigating and analyzing the effects of geometric parameters on the performance of interrupted flying-wing fins (IFWF). The incorporation of interruptions in the flying-wing fins (FWF) effectively enhances heat transfer efficiency, and increases flow resistance. Moreover, when the number of interruptions exceeds 3, the comprehensive performance of the heat exchanger is diminished. Numerical simulations are employed to thoroughly investigate the effects of geometric parameters individually, within the Reynolds number range of 600-1600, and correlations for the j and f-factor of the interrupted flying-wing fins (IFWF) are proposed using the responses surface method. The parametric study of the contribution ratio on the j-factor, f-factor, and JF-factor is obtained by the Taguchi method, including 18 cases with different combinations of key parameters. At a Reynolds number of 1000, it becomes evident that parameter A exerts the most substantial influence on the j-factor, f-factor, and JF-factor. Consequently, in the design of IFWF, prioritizing amplitude A is imperative.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"24 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135973432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Convective Heat Transfer and Entropy Generation Analysis in Elliptic Microchannels 椭圆微通道内对流换热及熵产分析

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063962

Liangbin Su, Yongyi Yang

{"title":"Convective Heat Transfer and Entropy Generation Analysis in Elliptic Microchannels","authors":"Liangbin Su, Yongyi Yang","doi":"10.1115/1.4063962","DOIUrl":"https://doi.org/10.1115/1.4063962","url":null,"abstract":"Abstract In this paper, we investigate analytically the first and the second law characteristics of fully developed gaseous slip flow with the H1 boundary condition through elliptical microchannels. The closed-form solution of temperature distribution was obtained with the separation of variables method. Expressions for the Nusselt number, the non-dimensional entropy generation rate, and the Bejan number were further deduced. The influences of crucial factors, including viscous dissipation, rarefaction, aspect ratio, and fluid axial heat conduction, have been carefully evaluated. The results indicated that viscous dissipation has a dramatic impact on heat transfer characteristics. But the rarefaction effect was found to significantly reduce the effect of the viscous dissipation on the Nusselt number, and the former may not deteriorate the heat transfer performance when considering the viscous dissipation. The main source of the entropy generation rate is controlled by fluid axial heat conduction when the Peclet number is less than one. The impacts of the viscous dissipation, the rarefaction, and the aspect ratio on entropy generation are magnified when fluid axial conduction dominates the irreversibility. The analytical solutions of the current study will make it possible to compare, evaluate, and optimize alternative elliptical microchannel heat exchanger design options.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"30 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135934162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 Study of Mixed Convection of Buoyant Twin Jet 浮力双射流混合对流的数值研究

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063959

Nassira Nouali, Mataoui Amina

{"title":"Numerical Study of Mixed Convection of Buoyant Twin Jet","authors":"Nassira Nouali, Mataoui Amina","doi":"10.1115/1.4063959","DOIUrl":"https://doi.org/10.1115/1.4063959","url":null,"abstract":"Abstract The effect of mixed convection of twin vertical jets is investigated numerically in this paper. The results are presented specifically for turbulent flows affected by buoyancy for two parallel jets of same velocities ranging between 0,25 m/s and 5,0 m/s and temperatures between 295 K and 320 K. Both jets generate a slow flow with a temperature difference (with the ambient flow) less or equal to 32°C. The prediction of dynamical and thermal parameters are obtained in the following main characteristic regions of the two jets: the merging zone, the combining region. This study reveals that the trajectory of the two jets is strongly influenced by the ratio of buoyancy to inertial forces. Results indicate that, relative to isotherm jets, the location along the vertical symmetry plane at which the two jets merge (merging point) decreases with increasing jet inlet temperature. It was also found that the decrease in the location of the merging point is shifted towards the confining wall as the velocity of the jets increases. The behavior law (linear regression), relating to the expansion of the jet, is not verified in the whole developed region for each value of the inlet velocity and temperature. This is explained by the fact that natural convection is predominant than forced convection. Results reveal that the self-similarity of the cross profiles of the mean velocity and the law of behavior relating to the expansion of the jet are checked throughout the developed region.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"22 19","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135973294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Pore-Scale Study of Gas Natural Convection In Confined Porous Media Based on Lattice Boltzmann Method 基于晶格玻尔兹曼方法的密闭多孔介质中气体自然对流的孔隙尺度研究

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-10-30 DOI: 10.1115/1.4063903

Ammar Tariq, Yueqi Zhao, Adnan Munir, Peilin Cui, Zhenyu Liu

{"title":"Pore-Scale Study of Gas Natural Convection In Confined Porous Media Based on Lattice Boltzmann Method","authors":"Ammar Tariq, Yueqi Zhao, Adnan Munir, Peilin Cui, Zhenyu Liu","doi":"10.1115/1.4063903","DOIUrl":"https://doi.org/10.1115/1.4063903","url":null,"abstract":"Abstract Gas natural convection is one common phenomenon in industrial applications, especially for the thermal management of electronic devices. In this study, a numerical model for gas natural convection in a confined porous cavity is constructed based on the lattice Boltzmann (LB) method, which predicts the density-difference-induced flow using a multiple relaxation time (MRT) collision operator. At the gas-solid interfaces, the micro-scale flow and heat transfer effects are formulated using an effective slip boundary condition. The established LB model is applied to investigate the Nusselt number for heated obstacles arranged in a staggered formation in the cavity. Based on the calculated data, the Nusselt number values obtained for a 5-cylinder pore-scale (single pore, SP) domain are analyzed and compared to those for a 13-cylinder (multi pore, MP) one. The Nusselt number shows a sharp decrease as soon as the micro-scale effect is considered at the obstacle walls. It was also observed that the Nusselt number for MP domain achieved lower values than that of SP one. The findings in this work can contribute to the design of thermal management device with confined porous media.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"28 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136103872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Developing A CFD-FEM Model To Analyze Thermal-Mechanical Stresses In A Heavy-Duty Medium-Speed Diesel Engine Piston During Warm-Up 建立了一种CFD-FEM模型来分析重型中速柴油机活塞在预热过程中的热机械应力

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-10-30 DOI: 10.1115/1.4063901

Nguyen Van Duong, Phuong Pham Xuan

{"title":"Developing A CFD-FEM Model To Analyze Thermal-Mechanical Stresses In A Heavy-Duty Medium-Speed Diesel Engine Piston During Warm-Up","authors":"Nguyen Van Duong, Phuong Pham Xuan","doi":"10.1115/1.4063901","DOIUrl":"https://doi.org/10.1115/1.4063901","url":null,"abstract":"Abstract Pistons play a vital role in internal combustion engines, affecting both performance and reliability, and are subjected to intense thermal-mechanical loads that have become more challenging due to improved engine efficiency and power. This study explores the impact of different engine warm-up modes on the combined stress experienced by a piston in a heavy-duty medium-speed diesel engine. This study focused on heavy-duty diesel engines, such as those used in heavy trucks, locomotives, and ships. The authors used a combination of CFD, FEM, and Matlab to consider factors such as oil temperature and flow rate, coolant temperature, component temperature, and boundary conditions during engine transient conditions. The results highlight the significant variations in the thermal and mechanical stress on the piston, particularly in the piston head zone, under different warming-up conditions. It is noted that the variation in oil temperature is a crucial factor affecting the thermal stress on the piston. Low oil temperature can result in reduced heat exchange coefficient and inadequate cooling of the piston due to low flow rate of the cooling oil. During engine warm-up, both thermal and combined stresses reach maximum values and then decrease when the engine reaches stable operating conditions. By selecting appropriate warming-up modes, the quality of the warm-up process and the strength and longevity of the engine could be improved. This study also provides useful insights for technicians to prevent critical conditions that may damage the piston and reduce its strength and lifespan.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"378 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136104745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 Whole-Core Transient Thermal Hydraulic Model For Fluoride Salt-Cooled Reactors 氟盐冷却堆全堆芯瞬态热水力模型

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-10-30 DOI: 10.1115/1.4063902

Sriram Chandrasekaran, Srinivas Garimella

{"title":"A Whole-Core Transient Thermal Hydraulic Model For Fluoride Salt-Cooled Reactors","authors":"Sriram Chandrasekaran, Srinivas Garimella","doi":"10.1115/1.4063902","DOIUrl":"https://doi.org/10.1115/1.4063902","url":null,"abstract":"Abstract A thermal hydraulic model is developed for a solid pin-fueled fluoride-salt-cooled small modular advanced high temperature reactor (SmAHTR). This pre-conceptual SmAHTR was developed by the Oak Ridge National Laboratory (ORNL). For the fuel assembly configuration investigated in this study, the fuel and non-fuel pins are arranged in a hexagonal layout. The molten FLiBe salt coolant flows parallel to the bank of pins. A finite volume model is developed and used to compute temperatures in the solid regions (fuel and non-fuel pins, and the graphite reflectors) in the core. The temperature, flow, and pressure profiles for the coolant flowing through the pin bundles in the core are calculated using the conventional subchannel methodology. Pertinent closure relations are used to compute the hydraulic losses, momentum and energy exchange between adjacent subchannels, and heat transfer between the solid and fluid regions. The resulting model can perform both steady-state and transient computations across the entire core. This fully implicit model also includes an adaptive time stepping algorithm for automatic time step adjustment. A preliminary code-to-code comparison demonstrates good agreement between the present subchannel-based model and a computational fluid dynamics (CFD)-based model for a transient case in which the core inlet flow rate varies with time. Following the code-to-code comparison, the thermal hydraulic model is used to analyze the protected loss of heat sink (P-LOHS) accident scenario.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"11 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136104851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Energy Modelling Of An Aquaculture Raceway 水产养殖跑道能量模型研究

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-10-21 DOI: 10.1115/1.4063868

Mitchell Kuska, Kamran Siddiqui, Christopher T. DeGroot

{"title":"Energy Modelling Of An Aquaculture Raceway","authors":"Mitchell Kuska, Kamran Siddiqui, Christopher T. DeGroot","doi":"10.1115/1.4063868","DOIUrl":"https://doi.org/10.1115/1.4063868","url":null,"abstract":"Abstract Large seasonal temperature variations in aquaculture source water leaves aquaculture ponds and raceways susceptible to temperature variations leading to non-optimal growing conditions. Such conditions may slow down the growth rate and make aquatic species vulnerable to disease and potential death, leading to economic setback for aquaculture farmers. Therefore, it is advantageous to predict the temperature of aquaculture raceways under the influence of seasonal variations and study the parameters that contribute to these variations. This allows one to develop strategies and processes to better regulate the raceway temperature to maximize its productivity. A numerical energy model was developed to simulate the temperature of water inside an aquaculture raceway, and a parametric study was conducted to investigate the influence of various key parameters on the raceway temperature. It was found that surface area and flow rate have a large effect on the raceway temperature, while depth of raceway had little effect. The largest surface area tested produced outlet temperatures and heat transfer values that were 6.2% and 76% higher, respectively, than the smallest surface area tested. Decreasing flow rate from the reference value of 43 L/s to 1 L/s resulted in an 83% increase in average outlet temperature. It was also observed that the variations in the ambient air temperature alone has negligible effect on the raceway temperature. The model was further implemented to simulate the temperature of raceways located at different geographical locations.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"100 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135512850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Effects of Hydraulic Parameters On the Retrieved Hydrothermal Dynamics of Unsaturated Soil Using a Synthetic Inverse Model 水力参数对非饱和土水热动力学反演的影响

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-10-18 DOI: 10.1115/1.4063450

Ernest Leontin Lemoubou, Jean Roger Bogning

引用次数: 0