ASME Journal of Heat and Mass Transfer最新文献_第6页

An Active Phantom Cooling Concept for Turbine Endwall Cooling From Pressure-Surface Film Coolant Injection 用于涡轮机端壁冷却的主动式幻影冷却概念（通过注入压力-表面薄膜冷却剂进行冷却

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-25 DOI: 10.1115/1.4064560

Xing Yang, Qiang Zhao, Hang Wu, Zhenping Feng

{"title":"An Active Phantom Cooling Concept for Turbine Endwall Cooling From Pressure-Surface Film Coolant Injection","authors":"Xing Yang, Qiang Zhao, Hang Wu, Zhenping Feng","doi":"10.1115/1.4064560","DOIUrl":"https://doi.org/10.1115/1.4064560","url":null,"abstract":"\u0000 Cooling of the endwall of a turbine vane should receive special attention due to its uniqueness of near-wall complex secondary flows and concomitant challenge of offering film-coverage for cooling the endwall pressure-side corner regions. The use of internal enhanced cooling at the endwall backside could be an option, but it increases manufacturing cost, adds weight to the component, causing excessive pressure losses in the secondary air system. Novel film cooling concepts are, therefore, required to provide effective cooling for these difficult-to-cool regions. This study proposes an active cooling concept effected by placing a row of film cooling holes on the vane pressure surface near the endwall with the intention of utilizing second-order cooling (or phantom cooling) from pressure-surface film-coolant injection to provide increased cooling effectiveness and enlarge coverage on the endwall. The effects of hole diameter, injection angle, and compound angle, as well as coolant injection rate are investigated. Detailed phantom cooling effectiveness over the endwall is documented using Pressure-Sensitive Paint (PSP). To provide a description of the flow physics driving the cooling process, computational modeling is carried out to document mixing of coolant with the freestream. Experiments show that significant cooling occurs in the endwall pressure-side corner and extends beyond the passage throat. Higher coolant injection rates and an optimized pressure-surface injection geometry maximize endwall phantom cooling. An effectiveness correlation for the active cooling is developed to provide a straightforward tool for designers to apply in turbine design.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":"15 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139597333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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 Correlation for Considering the Effect of Neighbouring Droplets On the Evaporation Rate of Solvent Droplets Used in Carbon Capture Applications 考虑邻近液滴对碳捕获应用中所用溶剂液滴蒸发率影响的新型相关方法

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-16 DOI: 10.1115/1.4064482

Gourav Parmar, Vignesh Kumar Dhinasekaran, O. Cejpek, J. Jedelský, Madan Mohan Avulapati

{"title":"A Novel Correlation for Considering the Effect of Neighbouring Droplets On the Evaporation Rate of Solvent Droplets Used in Carbon Capture Applications","authors":"Gourav Parmar, Vignesh Kumar Dhinasekaran, O. Cejpek, J. Jedelský, Madan Mohan Avulapati","doi":"10.1115/1.4064482","DOIUrl":"https://doi.org/10.1115/1.4064482","url":null,"abstract":"\u0000 Chemical sprays like Monoethanolamine (MEA) and aqueous ammonia are commonly used in spray columns to remove CO2 from combustion flue gases. This process involves interactions between spray droplets and the flue gas, resulting in both CO2 absorption and droplet evaporation due to temperature differences. The presence of neighboring droplets can influence the evaporation and gas absorption of a given droplet. Understanding this interaction is crucial for creating accurate models for CO2 capture from flue gases.This study investigated the impact of neighboring droplets on the evaporation of a specific droplet, comparing it to evaporation in isolation. Various configurations of suspended water, aqueous ammonia, and MEA droplets were examined across a temperature range from 75°C to 125°C. The droplets were placed on a microfiber grid and observed in a heating chamber. The evaporation rate was determined through image analysis and MATLAB algorithms, considering temperature and available surface area for vapor diffusion. Results demonstrated that neighboring droplets significantly influenced droplet evaporation, especially for MEA. A novel parameter, Surface Area Ratio (SAR), combining the number of droplets and their proximity, was introduced to account for this influence. The normalized evaporation rate correlated linearly with SAR, providing a basis for correcting evaporation rates in computational models across different conditions. This correlation between the normalized evaporation rate and SAR was developed from the collective data, offering a valuable tool for refining computational models of evaporation in CO2 capture processes.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":"47 47","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139528269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the Aero-Thermal Performance of Rim Film Cooling in the Squealer Tip of a Linear Turbine Cascade 论线性涡轮级联尖部缘膜冷却的气动热性能

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-12 DOI: 10.1115/1.4064273

L. Luo, Zhiqi Zhao, Dandan Qiu, Songtao Wang, Xun Zhou, Zhongqi Wang, Guangchao Li

{"title":"On the Aero-Thermal Performance of Rim Film Cooling in the Squealer Tip of a Linear Turbine Cascade","authors":"L. Luo, Zhiqi Zhao, Dandan Qiu, Songtao Wang, Xun Zhou, Zhongqi Wang, Guangchao Li","doi":"10.1115/1.4064273","DOIUrl":"https://doi.org/10.1115/1.4064273","url":null,"abstract":"\u0000 The present study proposes a novel rim film cooling design, motivated by the fact that the suction-side rim and the cavity floor near the leading edge of a conventional squealer tip with a camber-line film hole array are directly subjected to high-temperature gas. The new design consists of cooling injection for rim-hole or -slot cooling at the leading edge. The parameters of injection geometry and cavity depth are also discussed in this study. The flow physics, leakage flowrate, heat transfer characteristics, and vortices in the cavity are carefully analyzed. The results show that rim film cooling can substantially inhibit tip heat transfer and the amount of hot leakage flow. Compared with the typical design, the maximum and average heat transfer coefficients of the blade tip of the rim slot case are reduced by 12.83% and 5.43%,, respectively. The variation in cavity depth is sensitive to the heat transfer on the cavity floor of the squealer tip blade. With the optimal design, the average and maximum heat transfer coefficients are reduced by 14.42% and 14.21%,, respectively. In addition, the leakage flowrate can be reduced by a maximum of 3.67% by rim injection compared with the conventional squealer tip.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":"58 45","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139532821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Steady and Unsteady Complex Heat Transfer in Optically Thick Medium During Film Boiling 光学厚介质在薄膜沸腾过程中的稳定和非稳定复合传热

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-12 DOI: 10.1115/1.4064274

A. A. Avramenko, I. Shevchuk, M. Kovetskaya, Y. Kovetska, A. V. Konyk

{"title":"Steady and Unsteady Complex Heat Transfer in Optically Thick Medium During Film Boiling","authors":"A. A. Avramenko, I. Shevchuk, M. Kovetskaya, Y. Kovetska, A. V. Konyk","doi":"10.1115/1.4064274","DOIUrl":"https://doi.org/10.1115/1.4064274","url":null,"abstract":"\u0000 The paper presents the results of a study of radiative-convective heat transfer at film boiling of a liquid on a vertical heated plate. Both a steady-state problem of heat transfer and a transient problem were considered. The latter describes the instantaneous (flash) boiling up of a liquid on a heated surface. The novelty of the present study is the use of the optically thick medium approximation in a mathematical model when studying the process of radiation-convective heat transfer in the film boiling regime. For the first time, radiation heat transfer was considered for an optically thick medium. An analytical solution of the steady-state problems is obtained for boundary conditions involving a constant wall temperature and a constant wall heat flux. The effect of radiation and the temperature difference between the wall and liquid on the temperature profiles in the vapor phase is shown. The effect of radiation becomes more pronounced with an increase in the temperature difference between the wall and the liquid. As a result of solving the transient problem, the variation in time of the temperature profile and the heat transfer coefficient in the vapor film were obtained. The effect of radiation (Stark number) on the heat transfer coefficients is elucidated. An increase in the radiative heat flux leads to an increase in the Nusselt number, as well as the time it takes for the heat transfer process to reach a steady-state regime.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":" 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139625014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

3D Simulations of Nucleate Boiling with Sharp Interface Vof and Localized Adaptive Mesh Refinement in Ansys-Fluent 在 Ansys-Fluent 中利用锐化界面 Vof 和局部自适应网格细化进行核沸腾的三维模拟

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-10 DOI: 10.1115/1.4064459

Winston James, I. Perez-Raya

{"title":"3D Simulations of Nucleate Boiling with Sharp Interface Vof and Localized Adaptive Mesh Refinement in Ansys-Fluent","authors":"Winston James, I. Perez-Raya","doi":"10.1115/1.4064459","DOIUrl":"https://doi.org/10.1115/1.4064459","url":null,"abstract":"\u0000 The present work demonstrates the use of customized Ansys-Fluent in performing 3D numerical simulations of nucleate boiling with a sharp interface and adaptive mesh refinement. The developed simulation approach is a reliable and effective tool to investigate 3D boiling phenomena by accurately capturing the thermal and fluid dynamic interfacial vapor-liquid interaction and reducing computational time. These methods account for 3D sharp interface and thermal conditions of saturation temperature refining the mesh around the bubble edge. User-Defined-Functions (UDFs) were developed to customize the software Ansys-Fluent to preserve the interface sharpness, maintain saturation temperature conditions, and perform effective adaptive mesh refinement in a localized region around the interface. Adaptive mesh refinement is accomplished by a UDF that identifies the cells near the contact line and the liquid-vapor interface and applies the adaptive mesh refinement algorithms only at the identified cells. Validating the approach considered spherical bubble growth with an observed acceptable difference between theoretical and simulation bubble growth rates of 10%. Bubble growth simulations with water reveal an influence region of 2.7 times the departure bubble diameter, and average heat transfer coefficient of 15000 W/m2-K. In addition, the results indicate a reduced computational time of 75 hours using adaptive mesh compared to uniform mesh.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":"4 20","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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 Eccentric Jet Impingement Cooling On a Heated Cylindrical Surface 偏心射流对加热圆柱面的冲击冷却数值研究

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-10 DOI: 10.1115/1.4064456

V. Chauhan, Karuna Kumari, Pankaj Kumar, Vinod Kumar Venkiteswaran, Mohamed M. Awad

{"title":"Numerical Study of Eccentric Jet Impingement Cooling On a Heated Cylindrical Surface","authors":"V. Chauhan, Karuna Kumari, Pankaj Kumar, Vinod Kumar Venkiteswaran, Mohamed M. Awad","doi":"10.1115/1.4064456","DOIUrl":"https://doi.org/10.1115/1.4064456","url":null,"abstract":"\u0000 This article presents a comprehensive numerical analysis of the effects of cooling a cylinder using an eccentric Slot Jet Impingement Cooling (SJIC). The study focuses on examining the thermal and fluid behaviour when the slot jet is off-centre, during impingement cooling. Several turbulence models from the k-e and k-ε families were compared by evaluating the local Nusselt number profiles at different locations around the cylinder, and these results were compared to experimental data. The findings indicate that the SST k-ω model outperforms the other turbulence models in estimating the Nusselt number in the stagnation region, while the standard k-ω model shows improved performance elsewhere on the cylinder. Furthermore, this study reveals a decrease in the maximum local Nusselt number and a shift in the direction of the nozzle displacement. The presence of swirling/recirculating fluid at the trailing end of the cylinder enhances heat transfer near the back end of the cylinder. The separation and the reattachment of the fluid stream differ depending on the Reynolds number, with low Reynolds numbers resulting in reattachment on the side of the slot jet and higher Reynolds numbers leading to reattachment in the opposite direction. Additionally, the length of the recirculation and swirling zones increases as the nozzle-to-cylinder spacing (H/S) increases. However, as the eccentricity (E/S) increases, the size of the swirl circulation zones decreases and completely vanishes for E/S = 4. This study provides valuable insights for optimal cooling design.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":"3 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On a Rayleigh Structure in Temperature Waves 论温度波中的瑞利结构

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-10 DOI: 10.1115/1.4064460

Nassar Haidar

引用次数: 0

Thermal Analysis of Jet-In-Crossflow Technique for Hotspot Treatment in Electronics Cooling 用于电子冷却中热点处理的射流内交叉流技术的热分析

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-10 DOI: 10.1115/1.4064458

Christian Corvera, S. Mahjoob

{"title":"Thermal Analysis of Jet-In-Crossflow Technique for Hotspot Treatment in Electronics Cooling","authors":"Christian Corvera, S. Mahjoob","doi":"10.1115/1.4064458","DOIUrl":"https://doi.org/10.1115/1.4064458","url":null,"abstract":"\u0000 Artificial intelligence and machine learning systems, faster processors, miniaturized computational components, and supercomputer centers are accompanied by larger heat dissipation and the need for innovative cooling methods. In this work, a combined jet-in-crossflow cooling system is introduced and numerically investigated with an application in localized hotspot treatment. A validation study, a grid independence study, and an uncertainty analysis are conducted to ensure the accuracy of the obtained results. Both vertical and angled jet impingement at different jet locations are studied indicating the advantage of using a 45° angled jet placed upstream of the hotspot. In addition, the advantage of jet-in-crossflow in comparison with pure crossflow and pure jet impingement are studied. The results show that the angled jet-in-crossflow setup, in comparison with pure crossflow at the same overall mass flow rate, considerably reduces the temperature values at the heated surface, decreases the temperature standard deviation by 65%, while lowering the required pumping power by 35%. In comparison with pure jet impingement at the same overall mass flow rate, the angled jet-in-crossflow method reduces the required pumping power by 87%, while local temperature and temperature standard deviation values are very comparable. Furthermore, the advantage of structured rib channels in cooling effectiveness is investigated for the jet-in-crossflow setup. Although the addition of a rib slightly increases the pressure drop, the employment of a proper rib size minimizes the increased pressure drop while considerably improves the cooling effectiveness and temperature uniformity.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":"70 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139440733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In-Situ Measurement of Thermal Barrier Coating Properties via Induction Phase Radiometry - Methodology Development 通过感应相位辐射测量法原位测量隔热涂层性能--方法开发

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-10 DOI: 10.1115/1.4064457

Shani Eitan, S. Julius, B. Cukurel

{"title":"In-Situ Measurement of Thermal Barrier Coating Properties via Induction Phase Radiometry - Methodology Development","authors":"Shani Eitan, S. Julius, B. Cukurel","doi":"10.1115/1.4064457","DOIUrl":"https://doi.org/10.1115/1.4064457","url":null,"abstract":"\u0000 This research introduces a new method for accurately measuring the thermal resistance of thermal barrier coatings (TBCs), as typically used in gas turbine engines. The proposed method involves periodic internal heat generation inside the airfoil in the vicinity of the TBC-alloy boundary using low frequency modulated induction heating through a coil. The phase-lag between the radiation flux emitted to the surroundings from the exposed side of the TBC and the recorded voltage input to the modulated induction coil is proportional to the thermal resistance (L^2/a) of the thin film. A simplified analytical model is developed to quantify the relationship between the lag as a function of the thermal resistance and induction modulation frequency. Numerical experiments are conducted to solve the full physics. Comparing the output with the simplified model, precision of 0.8% under ideal conditions can be observed. Moreover, the robustness of the methodology to recover properties is characterized for differing levels and types of noise levels, including Gaussian and constant-lag biases. For the relevant application, it is found that the suggested approach maintains a recovery error bound to range of 1-10%, dependent on input noise level.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":"2 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modification of the Acoustic Mismatch Model and Diffuse Mismatch Model for Accurate Prediction of Interface Thermal Conductance At Low Temperatures 修改声错配模型和扩散错配模型以准确预测低温下的界面导热率

ASME Journal of Heat and Mass Transfer Pub Date : 2024-01-09 DOI: 10.1115/1.4064440

Nourhan Barakat, Fouad El Haj Hassan, Michel Kazan

{"title":"Modification of the Acoustic Mismatch Model and Diffuse Mismatch Model for Accurate Prediction of Interface Thermal Conductance At Low Temperatures","authors":"Nourhan Barakat, Fouad El Haj Hassan, Michel Kazan","doi":"10.1115/1.4064440","DOIUrl":"https://doi.org/10.1115/1.4064440","url":null,"abstract":"\u0000 Houston&amp;#39;s method for summing phonon modes in the Brillouin zone is applied to exclude specular transmission of phonon modes of specific symmetries, thus, modifying the Acoustic Mismatch Model when phonon heat flux is incident from a heavier to a lighter medium. The Houston method is also used to impose conservation of the number of phonons in each direction of high symmetry, thus modifying the detailed balance theorem and the Diffuse Mismatch Model. Based on the assumption that phonons are in equilibrium at the interface and are transmitted specularly or diffusely by two-phonon elastic processes, interpolation between the modified Acoustic Mismatch Model and the modified Diffuse Mismatch Model has led to a general analytical formalism for low-temperature interface thermal conductance. The Debye temperature, the only parameter in the derived formalism, is expressed as a function of temperature by assimilating numerically obtained specific heat values to the Debye expression for specific heat. Previous measurements of the thermal conductance of smooth and rough interfaces between dissimilar materials could be reproduced numerically without adjustment of model parameters, demonstrating the importance of modifications to the Acoustic Mismatch Model and the Diffuse Mismatch Model, and supporting the hypothesis that anharmonic processes play a minimal role in heat transport across interfaces below ambient temperature. The formalism developed is used to study the thermal conductance of the interface between silicon and germanium because of the potential of silicon-germanium nanocomposites for thermoelectric applications.","PeriodicalId":505153,"journal":{"name":"ASME Journal of Heat and Mass Transfer","volume":"1 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139444326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0