Journal of Thermal Engineering最新文献_第8页

Thermal insulation performance curves for exterior walls in heating and cooling seasons 供暖和制冷季节外墙的隔热性能曲线

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-02-08 DOI: 10.18186/thermal.1337469

M. A. Batiha, Saleh E. Rawadieh, M. Batiha, Leema A. Al-Makhadmeh, M. Kayfeci, Freabdullah Marachli

{"title":"Thermal insulation performance curves for exterior walls in heating and cooling seasons","authors":"M. A. Batiha, Saleh E. Rawadieh, M. Batiha, Leema A. Al-Makhadmeh, M. Kayfeci, Freabdullah Marachli","doi":"10.18186/thermal.1337469","DOIUrl":"https://doi.org/10.18186/thermal.1337469","url":null,"abstract":"Determination of thermal insulation performance (i.e. optimum insulation thickness, energy saving and payback period) is a tedious and time-consuming task that requires a thorough knowledge in thermal insulation engineering and economics. The main goal of this paper is to make the determination of insulation performance simple and timesaving by introduc-ing thermal insulation performance curves (TIPCs) from which the insulation performance can easily be found for any climate condition and all economic factors related to energy and insulation. These curves were generated based on a life-cycle cost analysis (LCCA) method. The curves can be easily read based on a single factor, called the f-factor, which comprises the number of degree-day, coefficient of performance, present worth factor, energy cost, and insu-lation cost. With the gain of heating and cooling degree days (i.e. HDD and CDD), TIPCs can be used for both heating and cooling loads. TIPCs cover commonly used insulation materials for building walls with thermal conductivities range from 0.020 to 0.055 W/m K. TIPCs were validated against published data.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46805631","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

Comment on “numerical analysis of heat transfer in multilayered skin tissue exposed to 5G mobile communication frequencies” by Jagbir Kaur and S.A. Khan Jagbir Kaur和美国Khan对“暴露于5G移动通信频率下的多层皮肤组织热传递的数值分析”的评论

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-31 DOI: 10.18186/thermal.1245331

P. Ben Ishai

引用次数: 0

Review on latent thermal energy storage using phase change material 相变材料潜热储能研究进展

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-31 DOI: 10.18186/thermal.1245298

Sattar Aljabair, Israa Alesbe, S. Ibrahim

{"title":"Review on latent thermal energy storage using phase change material","authors":"Sattar Aljabair, Israa Alesbe, S. Ibrahim","doi":"10.18186/thermal.1245298","DOIUrl":"https://doi.org/10.18186/thermal.1245298","url":null,"abstract":"One of the appealing technologies that contributes to raising the energy storage density is latent heat thermal energy storage. The heat of fusion is isothermally stored at a temperature representing the temperature at which a phase-change material transitions between phases. The current research provides a review of how phase transition materials are used in melting and solidification. Generally, the range of working temperature extends from -20 °C to 200 °C for solidification and melting applications. The first range (-20 to 5 °C) is employed for commercial and domestic refrigeration. The second range (5 to 40 °C) is utilized to lower the energy requirements for air-conditioning applications. The applications includes in third range (40 to 82 °C) are solar collector and heating of water. Applications of absorption cooling, waste electricity generations, and heat recovery are operated at high temperature range (82 to180 °C). There are various types of PCMs for all the above temperature ranges. The present review paper will discuss the application field, Geometry, PCM type, heat transfer augmentation technique and their effects on the performance. The conclusions are mentioned to give more insight about the PCM behavior in various applications.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42904218","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: 2

Advancements and challenges in the fluidized bed gasification system: A comprehensive review 流化床气化系统的进展与挑战:综述

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-31 DOI: 10.18186/thermal.1245279

Surender Antil, G. Sachdeva, Avdhesh Sharma

{"title":"Advancements and challenges in the fluidized bed gasification system: A comprehensive review","authors":"Surender Antil, G. Sachdeva, Avdhesh Sharma","doi":"10.18186/thermal.1245279","DOIUrl":"https://doi.org/10.18186/thermal.1245279","url":null,"abstract":"A gasifier employs partial ignition of biomass and conversion to gaseous fuels of high calorific value. Bubbling fluidized bed gasifier is a promising one amongst other gasification technologies like fixed bed, entrained flow etc. It has several noteworthy advantages like large- and small-scale applications, efficient heat and mass transfer rates due its fuel flexibility, low capital and operating costs, etc. However, low mixing rate of biomass feedstock and gasifying agent, high tar content in the product gas and low calorific value of producer gas are some of its limitations which need sincere attention to enhance its performance. The present study analyzes the effect of design variables of the proposed gasifier reactor for different feedstock along with the operating variables on the quality of producer gas. This review paper examines the present global status of biofuels, different types of gasification technologies, approaches adopted for the gasification, different parameters affecting gasification performance, enhancement of product gas conditioning, technical and cost-effective viability and the future prospects of gasification.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42995714","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

Evaluation of summer thermal comfort using in situ measurement and dynamic simulation, hot and arid climate in Algerian Saharan region as a case study 基于现场测量和动态模拟的夏季热舒适性评价——以阿尔及利亚-撒哈拉地区炎热干旱气候为例

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-31 DOI: 10.18186/thermal.1245164

Amri Khaoula, Alkama Djamel

{"title":"Evaluation of summer thermal comfort using in situ measurement and dynamic simulation, hot and arid climate in Algerian Saharan region as a case study","authors":"Amri Khaoula, Alkama Djamel","doi":"10.18186/thermal.1245164","DOIUrl":"https://doi.org/10.18186/thermal.1245164","url":null,"abstract":"The interest to ensure thermal comfort becomes one of the major challenges in the building sector, not only for the quality of interior ambiences, but also to minimize the energy rate consumed for heating and cooling systems. Th s paper presents the advantage of using the adaptive approach and numerical simulation to assess the level of thermal comfort of dwellings of different architectural typology in hot climate. For this purpose, the method is based on in situ measurements effected on two samples of traditional and contemporary typology; using anemometer instrument, where the climatic parameters measured inside and outside samples are: ambient temperature, relative humidity rate and air velocity. The simulation work is performed by Energy-Plus software; consequently experimental tests are realized on the local material in order to know their physical and thermal characteristics. The results obtained demonstrate the efficiency of the traditional passive devices, which are able to provide a comfortable thermal ambience without referring to the air conditioning system, with an operating temperature of 30.5ºC and a satisfaction rate of 80%.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49031336","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

Thermodynamic sensitivity analysis of SOFC integrated with blade cooled gas turbine hybrid cycle SOFC与叶片冷却燃气轮机混合循环的热力学敏感性分析

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-31 DOI: 10.18186/thermal.1245130

T. Choudhary, T. Verma, M. Sahu, U. Rajak, Sanyaj Sanyaj

{"title":"Thermodynamic sensitivity analysis of SOFC integrated with blade cooled gas turbine hybrid cycle","authors":"T. Choudhary, T. Verma, M. Sahu, U. Rajak, Sanyaj Sanyaj","doi":"10.18186/thermal.1245130","DOIUrl":"https://doi.org/10.18186/thermal.1245130","url":null,"abstract":"In the area of clean energy production along with higher efficiency, integrated combine power system, specifically gas turbine (GT) cycle with solid oxide fuel (SOFC) system, is gaining the attention of researchers. Thermodynamic modeling for the SOFC-GT hybrid cycle has been presented in this paper. For the proposed hybrid cycle, a high-temperature SOFC has successfully integrated with the recuperated-blade cooled gas turbine cycle. The gas turbine outlet waste heat has perfectly utilized the recuperator to power the fuel cell system. However, to maintain the temperature of the gas turbine blade within the permissible limit, air–film blade cooling scheme has been used. The SOFC-GT hybrid cycle has been operated under steady-state conditions, and a developed MATLAB program has been used to solve the governing equations for the components of the hybrid cycle. The impact of main operating parameters such as the temperature intake turbine (TIT), compression ratio (rpc), fuel utilization ratio (UF), and recirculation ratio are examined. From the obtained result, it can be revealed that the integration of the SOFC has seen significant improves overall hybrid cycle efficiency. The performance of fuel cell (SOFC) increases notably as the level of recuperation increases. To check the influence of main operating parameters, a sensitivity analysis has been performed for the hybrid cycle, and the maximum efficiency of 73% has been achieved. Moreover, to extend this research, an exclusive performance map has been plotted for power plant designers.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46614703","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

CFD modeling of influenza virus diffusion during coughing and breathing in a ventilated room 在通风室内咳嗽和呼吸时流感病毒扩散的CFD模拟

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-27 DOI: 10.18186/thermal.1243491

Sattar Aljabair, Israa Alesbe, A. Alkhalaf

{"title":"CFD modeling of influenza virus diffusion during coughing and breathing in a ventilated room","authors":"Sattar Aljabair, Israa Alesbe, A. Alkhalaf","doi":"10.18186/thermal.1243491","DOIUrl":"https://doi.org/10.18186/thermal.1243491","url":null,"abstract":"The virus diffusion in a ventilated room with the droplets produced by coughing and breathing are presented by the Lagrangian model. When the human body is located in the middle of the room with two locations of AC, in front of and behind the human body, three angles of Air Conditioning (AC) gate are applied 0°, 30°, and 60° to show droplet particle diffusion in the room in these cases. Three types of coughing velocity profiles were selected, real human coughing, sinusoidal cough, and cough jet with one velocity profile of breathing as a step function to cover the inhaling and exhaling cycle. The simulation results show that the uncovered standing in the middle of the room, are more susceptible to infection for the bouncy and forced flow around the human body. Droplet particle moves in the room as a random diffusion and it is very sensitive to the thermal load inside the room, generally depends on the bouncy force and pressure force due to convection heat transfer. when the AC location at the opposite direction of coughing flow, the droplet travels a distance of about 3 m, 2.85 m, and 2.75 m for real cough, sinusoidal cough, and cough jet respectively. While the droplet travel distance is about 3.1 m, 3.2 m, and 2.9 m when the AC location is at the same direction of coughing flow. Finally, the adopted CFD modeling was also used to show the effects of different AC locations on coughing, breathing particle droplets distribution in different indoor spaces, such as buildings, hospitals, and public transports, Also, showed good visual demonstration and representation of the real physical processes.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43230256","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: 1

Experimental investigation for heat transfer augmentation method of jet impingement using a fluid of different concentrations of water and ethylene glycol (EG) 不同水和乙二醇浓度射流冲击增热方法的实验研究

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-27 DOI: 10.18186/thermal.1243481

S. Lahane, P. Deshmukh, Manoj Nargade

{"title":"Experimental investigation for heat transfer augmentation method of jet impingement using a fluid of different concentrations of water and ethylene glycol (EG)","authors":"S. Lahane, P. Deshmukh, Manoj Nargade","doi":"10.18186/thermal.1243481","DOIUrl":"https://doi.org/10.18186/thermal.1243481","url":null,"abstract":"In the modern world, with rapid inventions in microscale electronics, devices suffers undesirable internal heat generation and, due to their tiny shapes, undergo large heat flux conditions. This emphasizes the development of effective and efficient heat dissipation methods to boost their performance and keep them in safe working conditions. The jet impingement cooling method is used for cooling purposes in many engineering applications, and is popular for quick removal of heat from the solid surfaces. The present experimental study is an investigation of effect impingement of jet of water and ethylene glycol mixture over a heated surface. The blending of ethylene glycol (C2H6O2) with water (H2O) as a base fluid enhances the average (convective) heat transfer coefficient (HTC). The cooling fluid with different concentrations of C2H6O2 varying from 10%, 25%, 50%, and 100% shows higher values of average convective coefficient at similar flow conditions than pure water. The fluid having mixture proportions 50% C2H6O2 and H2O shows an optimum value for heat transfer enhancement in the range of 30% to 75% than pure water at the same flow rates. It can be noted that based on mechanical stability and the cost associated, the experimental results reveal that the optimum value of the concentration of C2H6O2 in water is 50% for maximum heat transfer and at higher values of C2H6O2 hamper the mechanical stability and causes higher pumping power due to increase in viscosity of the fluid.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42981069","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

Control of noise and temperature using radial air injection inside engine silencer 利用发动机消声器内径向空气喷射控制噪声和温度

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-27 DOI: 10.18186/thermal.1243472

N. Deshmukh, Abhijit Waghmode

{"title":"Control of noise and temperature using radial air injection inside engine silencer","authors":"N. Deshmukh, Abhijit Waghmode","doi":"10.18186/thermal.1243472","DOIUrl":"https://doi.org/10.18186/thermal.1243472","url":null,"abstract":"Silencer is a device mainly used for attenuation of the engine exhaust noise. Several modifications were attempted to improve the performance of a silencer. In this paper experimental and simulation study was carried out to determine the effect of radial air injection on the temperature and sound pressure level. The radial air injection is introduced in the form of jets inside the silencer. The design of available silencer was studied, and the 3D model was prepared using CATIA software. Simulation study was carried out using ANSYS Fluent, to determine the temperature distribution inside the silencer with and without modification. The radial jets at different pressure were introduced inside the silencer at three different locations. To acquire sound pressure level and temperatures at different locations, Lab View software and FFT analyser were used. The performance of silencer is analysed by comparing temperature of exhaust gases and sound pressure level at constant speed of 3000 rpm. With radial air jets of 2 bar reservoir pressure at three different location Overall Sound Pressure Level reduces by 6 dB and 42 K reduction in temperature of exhaust gases.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46826253","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: 1

Energy, exergy analysis and optimization of insulation thickness on buildings in a low-temperature district heating system 低温区域供暖系统中建筑保温层厚度的能量、火用分析与优化

IF 1.1

Journal of Thermal Engineering Pub Date : 2023-01-27 DOI: 10.18186/thermal.1243502

Meryem Terhan, Sena Saliha Abak

{"title":"Energy, exergy analysis and optimization of insulation thickness on buildings in a low-temperature district heating system","authors":"Meryem Terhan, Sena Saliha Abak","doi":"10.18186/thermal.1243502","DOIUrl":"https://doi.org/10.18186/thermal.1243502","url":null,"abstract":"In the study, energy and exergy analysis of the buildings on a campus in Turkey are conducted by using actual operating data and taking measurements in the district heating system as a case study. The energy and exergy demands, losses that stem from all buildings are calculated according to average daily outdoor temperature data. Due to the high heat losses in the buildings, determining the optimal insulation thickness for the exterior wall should be investigated. Therefore, optimal insulation thicknesses, energy savings, fuel consumptions and payback periods of the insulation material on the exterior wall of the building are examined by using Life Cycle Assessment and P1–P2 method for natural gas. Optimal insulation thicknesses are calculated for different insulation materials such as XPS, glass wool, rock wool and EPS for the climatic regions (HDD=800–4250°C days). According to average exergy losses from the building components per unit area, the average total exergy loss is calculated as 2.39×10-2 kW/m2.year and 1.42×10-3 kW/m2 (5.92%) of this loss stems from the exterior walls, 1.93×10-3 kW/m2 (8.07%) from the floors, 7.37×10-4 kW/m2 (3.08%) from the roofs, 1.58×10-2 kW/m2 (65.99%) from the windows and doors, 4.04×10-3 kW/m2 (16.92%) from the ventilation with infiltration. Energy requirement values of the building are found between 2.68–25.70 kWh/m3 towards from the warmest to the coldest climatic region for the uninsulated wall. In the un-insulated state, fuel consumption varies between 1.93-18.48 m3/m2 from the warmest to the coldest region. The optimal insulation thickness values of the building’s exterior wall are calculated as between 2.3–10.0 cm according to different climatic regions. In-state of exterior wall insulation of 3 cm, fuel consumption decreases by 46.63%–53.46% compared to different insulation materials and climatic regions compared to the un-insulated state.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49346424","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: 2