Pub Date : 2023-10-17DOI: 10.18186/thermal.1377200
Ahmet ŞUMNU, İbrahim GÜZELBEY
In the present study, missile aerodynamic analysis is performed using different wing config-urations at subsonic and transonic speeds. The wing is critical component in point of aero-dynamic efficiency for a missile that speed is especially closer to transonic level because of flow separation. Flow on the wings may adversely effect tailfins of missile at high speed since it may cause vortex generation and flow disturbances. There are few studies that investigate the missile wing using different configurations at critical speeds when examined the previ-ous studies. Therefore, in this study, three different wing configurations are investigated and aerodynamic performance is compared with each other at 0.7 and 0.9 Mach numbers and 5° angle of attack (AoA). In beginning of this study, missile model with only tailfins is selected from previous study that contains experimental data. Because the experimental data for the selected missile model are available at supersonic speeds, the aerodynamic analysis to verify the solutions is carried out at supersonic speeds. After wing is mounted to the selected missile, aerodynamic analysis is carried out using three different wing configurations that are Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered wings. Lift to drag ratio (CL/CD) is calculated to compare wing configurations and it is concluded that Tapered Leading Edge wing configuration shows higher performance then other wing configurations. CL/CD values are 2.327, 2.306, 2.303 at 0.7 Mach number and 2.45, 2.429, 2.423 at 0.9 Mach number for Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered, respectively. When the results are compared each other, CL/CD values at 0.9 Mach number is higher about % 5.28, %5.33 and %5.21 than the CL/CD values at 0.7 Mach number for missile with Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered, respectively.
{"title":"The effects of different wing configurations on missile aerodynamics","authors":"Ahmet ŞUMNU, İbrahim GÜZELBEY","doi":"10.18186/thermal.1377200","DOIUrl":"https://doi.org/10.18186/thermal.1377200","url":null,"abstract":"In the present study, missile aerodynamic analysis is performed using different wing config-urations at subsonic and transonic speeds. The wing is critical component in point of aero-dynamic efficiency for a missile that speed is especially closer to transonic level because of flow separation. Flow on the wings may adversely effect tailfins of missile at high speed since it may cause vortex generation and flow disturbances. There are few studies that investigate the missile wing using different configurations at critical speeds when examined the previ-ous studies. Therefore, in this study, three different wing configurations are investigated and aerodynamic performance is compared with each other at 0.7 and 0.9 Mach numbers and 5° angle of attack (AoA). In beginning of this study, missile model with only tailfins is selected from previous study that contains experimental data. Because the experimental data for the selected missile model are available at supersonic speeds, the aerodynamic analysis to verify the solutions is carried out at supersonic speeds. After wing is mounted to the selected missile, aerodynamic analysis is carried out using three different wing configurations that are Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered wings. Lift to drag ratio (CL/CD) is calculated to compare wing configurations and it is concluded that Tapered Leading Edge wing configuration shows higher performance then other wing configurations. CL/CD values are 2.327, 2.306, 2.303 at 0.7 Mach number and 2.45, 2.429, 2.423 at 0.9 Mach number for Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered, respectively. When the results are compared each other, CL/CD values at 0.9 Mach number is higher about % 5.28, %5.33 and %5.21 than the CL/CD values at 0.7 Mach number for missile with Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered, respectively.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944358","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}
Pub Date : 2023-08-06DOI: 10.18186/thermal.1401660
Darshan Karanje, Shivroop Patil, Shivraj Gursal, P. Hatte
Proper ventilation is a critical consideration for the comfort of hospitalized patients. Dry skin, skin rashes, weariness, poor sleep, and other concerns caused by insufficient ventilation can all be avoided with proper ventilation. Air-Ventilated Air Beds are used to supply air to the major parts of the patient’s body. This air bed is constructed in such a way that air is circulated con-tinually throughout the body of the hospitalized patient. It is especially beneficial for people who are bedridden and need to spend a significant amount of time in bed due to illness. Exces-sive heat generated between the bed and the patient is perhaps the common cause of bedsores. Sweating is the leading cause of bedsores. Air ventilation is included in the system to prevent sweating and reduce the incidences of bedsores. Dual compressors, rubber tubes, flow control valves, and anti-decubitus mattresses are among the components used. The rubber tubes are used to ventilate the space between the body of the patient and the upper surface of the air bed. Above the mattress, the rubber tube mesh is positioned. The air is first compressed in two compressors before passing through the distribution manifold and through the meshing. The tubes are altered by drilling holes at certain intervals. The air from the compressor is circulated through the pipes before passing through the openings in the pipes. The unrestricted passage of compressed air via a capillary tube lowers the temperature of the air. The air exhausted through the capillary tubes maintains the patient’s body temperature stable for a while before lowering it. The air is ventilated throughout the bed in this manner. Bedsore can be avoided by reduction of sweat by using the air in close contact with the patient.
{"title":"Design and development of air ventilated air bed for hospitalized patients","authors":"Darshan Karanje, Shivroop Patil, Shivraj Gursal, P. Hatte","doi":"10.18186/thermal.1401660","DOIUrl":"https://doi.org/10.18186/thermal.1401660","url":null,"abstract":"Proper ventilation is a critical consideration for the comfort of hospitalized patients. Dry skin, skin rashes, weariness, poor sleep, and other concerns caused by insufficient ventilation can all be avoided with proper ventilation. Air-Ventilated Air Beds are used to supply air to the major parts of the patient’s body. This air bed is constructed in such a way that air is circulated con-tinually throughout the body of the hospitalized patient. It is especially beneficial for people who are bedridden and need to spend a significant amount of time in bed due to illness. Exces-sive heat generated between the bed and the patient is perhaps the common cause of bedsores. Sweating is the leading cause of bedsores. Air ventilation is included in the system to prevent sweating and reduce the incidences of bedsores. Dual compressors, rubber tubes, flow control valves, and anti-decubitus mattresses are among the components used. The rubber tubes are used to ventilate the space between the body of the patient and the upper surface of the air bed. Above the mattress, the rubber tube mesh is positioned. The air is first compressed in two compressors before passing through the distribution manifold and through the meshing. The tubes are altered by drilling holes at certain intervals. The air from the compressor is circulated through the pipes before passing through the openings in the pipes. The unrestricted passage of compressed air via a capillary tube lowers the temperature of the air. The air exhausted through the capillary tubes maintains the patient’s body temperature stable for a while before lowering it. The air is ventilated throughout the bed in this manner. Bedsore can be avoided by reduction of sweat by using the air in close contact with the patient.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139351563","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}
Pub Date : 2023-08-04DOI: 10.18186/thermal.1333904
Umutcan OLMUŞ, Yunus Emre GÜZELEL, Kamil NEYFEL ÇERÇI, Orhan BÜYÜKALACA
The main energy input of a desiccant air conditioning system is the low-quality thermal ener-gy required for regeneration, which can be obtained from waste heat, geothermal resources or solar energy. Regeneration thermal energy can be produced as well as energizing components such as fans, pumps, auxiliary air heaters, and control elements of the system by using pho-tovoltaic-thermal solar collectors (PV/T). In this study, parametric analyzes were performed to investigate the effect of regeneration temperature and air frontal velocity on the tempera-ture and dehumidification performance of a solid silica-gel desiccant wheel and on the wa-ter-cooled PV/T collectors used to provide the regeneration thermal energy. The regeneration temperature was varied between 50 and 70°C, and air frontal velocity between 1.3 and 4.1 m/s. The analyzes show that the dehumidification efficiency increases from 13.94% to 33.04% as regeneration temperature increased from 50°C to 70°C at 1.3 m/s air frontal velocity at which dehumidification efficiency is maximum. At 4.1 m/s air frontal velocity, the required regener-ation thermal energy is maximum and increases from 49.64 kW to 132.48 kW at the same re-generation temperature change. The low regeneration temperature resulted in desirable latent performance and undesirable sensible heat transfer performance in DEW. Finally, considering the whole system, it was concluded that the optimum regeneration air temperature for the performance parameters is 60°C.
{"title":"Effect of operating parameters on the performance of rotary desiccant wheel energized by PV/T collectors","authors":"Umutcan OLMUŞ, Yunus Emre GÜZELEL, Kamil NEYFEL ÇERÇI, Orhan BÜYÜKALACA","doi":"10.18186/thermal.1333904","DOIUrl":"https://doi.org/10.18186/thermal.1333904","url":null,"abstract":"The main energy input of a desiccant air conditioning system is the low-quality thermal ener-gy required for regeneration, which can be obtained from waste heat, geothermal resources or solar energy. Regeneration thermal energy can be produced as well as energizing components such as fans, pumps, auxiliary air heaters, and control elements of the system by using pho-tovoltaic-thermal solar collectors (PV/T). In this study, parametric analyzes were performed to investigate the effect of regeneration temperature and air frontal velocity on the tempera-ture and dehumidification performance of a solid silica-gel desiccant wheel and on the wa-ter-cooled PV/T collectors used to provide the regeneration thermal energy. The regeneration temperature was varied between 50 and 70°C, and air frontal velocity between 1.3 and 4.1 m/s. The analyzes show that the dehumidification efficiency increases from 13.94% to 33.04% as regeneration temperature increased from 50°C to 70°C at 1.3 m/s air frontal velocity at which dehumidification efficiency is maximum. At 4.1 m/s air frontal velocity, the required regener-ation thermal energy is maximum and increases from 49.64 kW to 132.48 kW at the same re-generation temperature change. The low regeneration temperature resulted in desirable latent performance and undesirable sensible heat transfer performance in DEW. Finally, considering the whole system, it was concluded that the optimum regeneration air temperature for the performance parameters is 60°C.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136119647","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}
Pub Date : 2023-07-16DOI: 10.18186/thermal.1335677
V. Kolhe, S. Pawar, Vishal D. Chaudhari, R. Edlabadkar, Sandipkumar Sonawane
The paper outlines the progression of a mathematical model using the Taguchi approach to analyze the performance of a Coriolis mass flow meter (CMFM). The sensor position, exci-tation frequency, and flow rate parameters were optimized using the Taguchi method for the meter’s maximum time-lag output. An orthogonal array of experiments was designed, and the time lag results were obtained for two tube configurations (viz. Omega and Diamond) and parameter levels. The obtained data was analyzed using analysis of variance (ANOVA) to understand the relationship between the variables and the time lag. The results showed that the Omega tube configuration exhibited a lower percentage error compared to the Diamond tube configuration. Additionally, an increase in flow rate led to a decrease in the error. The regression models fitted the experimental data well, with high R2 values indicating a good fit. The ANOVA showed the factors’ importance in affecting the time lag and the levels of interac-tion between the best individual parameters for maximizing the outcome. The most important factors affecting the Omega and Diamond tube configurations’ maximum performance have been identified as the flow rate and sensor position, respectively. This study offers a system-atic method for optimizing sensor parameters and provides light on how CMFMs behave in laminar flow. The experimental setup and mathematical model also serve as a basis for future research and advancements in CMFM design and functionality.
{"title":"Parameter optimization of coriolis mass flow meter in laminar flow regime using Doe-Taguchi method","authors":"V. Kolhe, S. Pawar, Vishal D. Chaudhari, R. Edlabadkar, Sandipkumar Sonawane","doi":"10.18186/thermal.1335677","DOIUrl":"https://doi.org/10.18186/thermal.1335677","url":null,"abstract":"The paper outlines the progression of a mathematical model using the Taguchi approach to analyze the performance of a Coriolis mass flow meter (CMFM). The sensor position, exci-tation frequency, and flow rate parameters were optimized using the Taguchi method for the meter’s maximum time-lag output. An orthogonal array of experiments was designed, and the time lag results were obtained for two tube configurations (viz. Omega and Diamond) and parameter levels. The obtained data was analyzed using analysis of variance (ANOVA) to understand the relationship between the variables and the time lag. The results showed that the Omega tube configuration exhibited a lower percentage error compared to the Diamond tube configuration. Additionally, an increase in flow rate led to a decrease in the error. The regression models fitted the experimental data well, with high R2 values indicating a good fit. The ANOVA showed the factors’ importance in affecting the time lag and the levels of interac-tion between the best individual parameters for maximizing the outcome. The most important factors affecting the Omega and Diamond tube configurations’ maximum performance have been identified as the flow rate and sensor position, respectively. This study offers a system-atic method for optimizing sensor parameters and provides light on how CMFMs behave in laminar flow. The experimental setup and mathematical model also serve as a basis for future research and advancements in CMFM design and functionality.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46228968","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}
Pub Date : 2023-05-22DOI: 10.18186/thermal.1300835
C. Derbal, Abdallah Haouama
In this paper, the mixed refrigeration cycle of Skikda APCI (Air Products and Chemicals Inc.) process in Algeria was studied thermodynamically in order to determine the optimal operat-ing conditions. The energy and exergy balance equations for each process component were es-tablished. The distribution of the exergy destruction of the basic cycle equipment revealed that the compressors had the highest exergy destruction rate. The effects of operating conditions on performance coefficient of the cycle (COP) and exergy efficiency of the APCI process were evaluated; mainly the inlet temperature of the compressors, natural gas (NG) temperature af-ter cooling in the main cryogenic heat exchanger (MCHE) and inlet temperature of the mixed refrigerant (MR) expansion valve. The results of the numerical simulation validated using Aspen HYSYS software indicate that the COP and exergy efficiency of the basic cycle are 2.66 and 59.99% respectively. These results can be improved by reducing the inlet temperature of the compressor and the expander as well as that of the NG after cooling in the MCHE. Finally, the results of the optimization performed using the genetic algorithms (GA) are in agreement with those of the literature. They show signs of improvement in the COP and exergy efficiency of the APCI process by 1.48% and 3.64% respectively compared to the basic cycle.
本文对阿尔及利亚Skikda APCI（Air Products and Chemicals股份有限公司）工艺的混合制冷循环进行了热力学研究，以确定最佳运行条件。建立了各工艺部件的能量和火用平衡方程。基本循环设备的火用破坏分布表明，压缩机的火用损坏率最高。评价了运行条件对APCI工艺循环性能系数（COP）和火用效率的影响；主要是压缩机的入口温度、在主低温热交换器（MCHE）中冷却后的天然气（NG）温度和混合制冷剂（MR）膨胀阀的入口温度。使用Aspen HYSYS软件验证的数值模拟结果表明，基本循环的COP和火用效率分别为2.66%和59.99%。这些结果可以通过降低压缩机和膨胀机的入口温度以及在MCHE中冷却后的NG的入口温度来改善。最后，使用遗传算法（GA）进行的优化结果与文献中的结果一致。与基本循环相比，APCI工艺的COP和火用效率分别提高了1.48%和3.64%。
{"title":"Thermodynamic analysis of the apci skikda liquefaction process","authors":"C. Derbal, Abdallah Haouama","doi":"10.18186/thermal.1300835","DOIUrl":"https://doi.org/10.18186/thermal.1300835","url":null,"abstract":"In this paper, the mixed refrigeration cycle of Skikda APCI (Air Products and Chemicals Inc.) process in Algeria was studied thermodynamically in order to determine the optimal operat-ing conditions. The energy and exergy balance equations for each process component were es-tablished. The distribution of the exergy destruction of the basic cycle equipment revealed that the compressors had the highest exergy destruction rate. The effects of operating conditions on performance coefficient of the cycle (COP) and exergy efficiency of the APCI process were evaluated; mainly the inlet temperature of the compressors, natural gas (NG) temperature af-ter cooling in the main cryogenic heat exchanger (MCHE) and inlet temperature of the mixed refrigerant (MR) expansion valve. The results of the numerical simulation validated using Aspen HYSYS software indicate that the COP and exergy efficiency of the basic cycle are 2.66 and 59.99% respectively. These results can be improved by reducing the inlet temperature of the compressor and the expander as well as that of the NG after cooling in the MCHE. Finally, the results of the optimization performed using the genetic algorithms (GA) are in agreement with those of the literature. They show signs of improvement in the COP and exergy efficiency of the APCI process by 1.48% and 3.64% respectively compared to the basic cycle.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45262529","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}
Pub Date : 2023-05-22DOI: 10.18186/thermal.1300538
W. Akram, M. Parvez, Osama Khan
Rapid deterioration of environment has led researchers to explore feasible forms of energy which could produce multiple energy forms with minimum inputs. Hence, in this study a nov-el trigeneration setup is explored so as to achieve simultaneous forms of energy in the form of electrical energy, heating and cooling, driving its primary energy requirements through a solar power tower. Molten salt is used in this study to transfer the heat from the solar component to the vapor absorption apparatus. Further the vapor absorption system is tested for thermody-namic performance for a couple of refrigerants (LiNO3-H2O and LiBr-H2O), so as to establish the Pareto-optimal fluid among them. In order to remove any adherent error in the measuring procedure, all equipment’s uncertainty analysis was performed which was negligibly small approximately at 5.34 % in terms of power plant efficiencies. An exact analysis was performed so as to estimate energy and exergy in efficiencies in the equipment while varying input pa-rameters. Zenith exergy destruction was achieved in 33.6% by the central receiver, followed by 24.9% by heliostat, and 7.8% in heat recovery steam generator. The highest energy and exergy efficiencies (62.6% and 20.6%) are attained on system working on LiBr-H2O, whereas (60.9% and 19.6%) were obtained in LiNO3-H2O operated system.
{"title":"Parametric analysis of solar-assisted trigeneration system based on energy and exergy analyses","authors":"W. Akram, M. Parvez, Osama Khan","doi":"10.18186/thermal.1300538","DOIUrl":"https://doi.org/10.18186/thermal.1300538","url":null,"abstract":"Rapid deterioration of environment has led researchers to explore feasible forms of energy which could produce multiple energy forms with minimum inputs. Hence, in this study a nov-el trigeneration setup is explored so as to achieve simultaneous forms of energy in the form of electrical energy, heating and cooling, driving its primary energy requirements through a solar power tower. Molten salt is used in this study to transfer the heat from the solar component to the vapor absorption apparatus. Further the vapor absorption system is tested for thermody-namic performance for a couple of refrigerants (LiNO3-H2O and LiBr-H2O), so as to establish the Pareto-optimal fluid among them. In order to remove any adherent error in the measuring procedure, all equipment’s uncertainty analysis was performed which was negligibly small approximately at 5.34 % in terms of power plant efficiencies. An exact analysis was performed so as to estimate energy and exergy in efficiencies in the equipment while varying input pa-rameters. Zenith exergy destruction was achieved in 33.6% by the central receiver, followed by 24.9% by heliostat, and 7.8% in heat recovery steam generator. The highest energy and exergy efficiencies (62.6% and 20.6%) are attained on system working on LiBr-H2O, whereas (60.9% and 19.6%) were obtained in LiNO3-H2O operated system.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67514818","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}
Pub Date : 2023-05-22DOI: 10.18186/thermal.1300432
H. Lakrafli, P. André, M. Sennoune, K. Lekouch, Yassin Sadiki
Improving the energy performance of passive energy buildings is based on reducing their consumption. These reach very high levels in overheating periods because of the mechanical ventilation systems. This work proposes to implement ventilation strategies to reduce the in-door temperature of an academic building considered a passive solar structure and designed to benefit as much as possible from solar radiation. Using TRNSYS software, with its two components, TRNBUILD and TRNFLOW, different likely scenarios were tested and allowed to identify significant results. The mechanical extraction system is a solution if the extraction threshold temperature is 21-19°C to keep the Hall_1 temperature lower. While, to make the temperature of all areas of the building more comfortable, three natural ventilation scenarios were evaluated. Obtained results highlight that natural ventilation scenario (circuit 2) is the optimal scenario which makes the different zones very comfortable and lowers the tempera-ture by an average of 4°C compared to mechanical ventilation. Thanks to the proposed venti-lation scenarios, we have shown that we can, thanks to natural ventilation, renew the air inside the different areas of the building and maintain the comfort temperature. Natural ventilation can be an alternative to mechanical ventilation if we consider appropriate scenarios. This will strongly reduce energy consumption.
{"title":"Toward improving thermal behavior of passive solar structures by natural ventilation and extraction – case study –","authors":"H. Lakrafli, P. André, M. Sennoune, K. Lekouch, Yassin Sadiki","doi":"10.18186/thermal.1300432","DOIUrl":"https://doi.org/10.18186/thermal.1300432","url":null,"abstract":"Improving the energy performance of passive energy buildings is based on reducing their consumption. These reach very high levels in overheating periods because of the mechanical ventilation systems. This work proposes to implement ventilation strategies to reduce the in-door temperature of an academic building considered a passive solar structure and designed to benefit as much as possible from solar radiation. Using TRNSYS software, with its two components, TRNBUILD and TRNFLOW, different likely scenarios were tested and allowed to identify significant results. The mechanical extraction system is a solution if the extraction threshold temperature is 21-19°C to keep the Hall_1 temperature lower. While, to make the temperature of all areas of the building more comfortable, three natural ventilation scenarios were evaluated. Obtained results highlight that natural ventilation scenario (circuit 2) is the optimal scenario which makes the different zones very comfortable and lowers the tempera-ture by an average of 4°C compared to mechanical ventilation. Thanks to the proposed venti-lation scenarios, we have shown that we can, thanks to natural ventilation, renew the air inside the different areas of the building and maintain the comfort temperature. Natural ventilation can be an alternative to mechanical ventilation if we consider appropriate scenarios. This will strongly reduce energy consumption.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42026492","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}
Pub Date : 2023-05-22DOI: 10.18186/thermal.1300859
Ajay Mahaputra Kumar, S. Verma
Excessive energy use has caused a disturbance in the planet’s life support system. It has created an adverse impact on water and natural resources. Power generation from solid waste can be an alternative to reduce waste volume and has an extra advantage in cleaning the surround-ing with the gain of electric power supply. Innovative technologies and future perspectives of MSWI were highlighted. Moreover, the latest understanding of immobilization mecha-nisms and advanced characterization technologies were elaborated to foster the future design of treatment technologies and the actualization of sustainable management for MSWI. Solid waste to energy conversion provides economic and atmospheric benefits by introducing re-newableenergy sources at minimum environmental influences.This analysis has focused on MSW to energy conversion system by incineration technique to generate electricity along with other bi-product and determines the system’s financial feasibility. The experiment has been conducted to calculate the physio-chemical characteristics of municipal waste with a bomb calorimeter and incinerator for electricity generation. Solid waste characteristics like chemical exergy, entropy, higher heating point, energy flux, and potential have been analyzed for the in-cineration technique’s viability.The thermal properties have been analytically described in the experiment. The result shows that MSW has a higher calorific value of 8.5-12.5 Mega Joule/kg, and charcoal has a higher calorific value of 27-32 Megajoule/kg.It also analyses that one-ton MSW can produce 600 kWh electricity with 360 gm CO2-eq/kWh generation.
{"title":"Experimental analysis for thermodynamic characteristics of municipal solid waste for energy generation with environmental and economic assessment in Indian scenario","authors":"Ajay Mahaputra Kumar, S. Verma","doi":"10.18186/thermal.1300859","DOIUrl":"https://doi.org/10.18186/thermal.1300859","url":null,"abstract":"Excessive energy use has caused a disturbance in the planet’s life support system. It has created an adverse impact on water and natural resources. Power generation from solid waste can be an alternative to reduce waste volume and has an extra advantage in cleaning the surround-ing with the gain of electric power supply. Innovative technologies and future perspectives of MSWI were highlighted. Moreover, the latest understanding of immobilization mecha-nisms and advanced characterization technologies were elaborated to foster the future design of treatment technologies and the actualization of sustainable management for MSWI. Solid waste to energy conversion provides economic and atmospheric benefits by introducing re-newableenergy sources at minimum environmental influences.This analysis has focused on MSW to energy conversion system by incineration technique to generate electricity along with other bi-product and determines the system’s financial feasibility. The experiment has been conducted to calculate the physio-chemical characteristics of municipal waste with a bomb calorimeter and incinerator for electricity generation. Solid waste characteristics like chemical exergy, entropy, higher heating point, energy flux, and potential have been analyzed for the in-cineration technique’s viability.The thermal properties have been analytically described in the experiment. The result shows that MSW has a higher calorific value of 8.5-12.5 Mega Joule/kg, and charcoal has a higher calorific value of 27-32 Megajoule/kg.It also analyses that one-ton MSW can produce 600 kWh electricity with 360 gm CO2-eq/kWh generation.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43260417","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}
Pub Date : 2023-05-22DOI: 10.18186/thermal.1300390
Ayhan Nazmi Ilikan, R. Aydin
Two-dimensional developing flow in the entrance of a microchannel has been studied numer-ically. Due to its nature, a microchannel can be used in tight space applications and the length of channel can get very small values. Furthermore, if the hydrodynamic development length of flow in microchannel has comparably the same value with the channel length, the channel entrance parameters play critical role on the flow performance of a microscale channel. Lattice Boltzmann Method (LBM) was considered for studying and simulating the developing slip flows through a rectangular microchannel. A unique computational code for this study was developed by using LBM. The slip velocity boundary condition along with Knudsen number values in the slip flow regime was used for this model. The bounce-back boundary condition was considered at the top and bottom walls of the microchannel. The effects of the Reyn-olds numbers (1-100) and Knudsen numbers (0.001, 0.01, 0.1) on the hydrodynamic entrance length has been examined. The numerical results have been compared with the previous stud-ies in the literature and the similarities have been found satisfactory. The entrance length is found to be increasing with the increase of Reynolds and Knudsen numbers. A correlation for hydrodynamic development length as a function of Knudsen and Reynolds numbers was obtained by using the data extracted from LBM simulations performed in this study.
{"title":"Analysis of the slip flow in the hydrodynamic entrance region of a 2D microchannel","authors":"Ayhan Nazmi Ilikan, R. Aydin","doi":"10.18186/thermal.1300390","DOIUrl":"https://doi.org/10.18186/thermal.1300390","url":null,"abstract":"Two-dimensional developing flow in the entrance of a microchannel has been studied numer-ically. Due to its nature, a microchannel can be used in tight space applications and the length of channel can get very small values. Furthermore, if the hydrodynamic development length of flow in microchannel has comparably the same value with the channel length, the channel entrance parameters play critical role on the flow performance of a microscale channel. Lattice Boltzmann Method (LBM) was considered for studying and simulating the developing slip flows through a rectangular microchannel. A unique computational code for this study was developed by using LBM. The slip velocity boundary condition along with Knudsen number values in the slip flow regime was used for this model. The bounce-back boundary condition was considered at the top and bottom walls of the microchannel. The effects of the Reyn-olds numbers (1-100) and Knudsen numbers (0.001, 0.01, 0.1) on the hydrodynamic entrance length has been examined. The numerical results have been compared with the previous stud-ies in the literature and the similarities have been found satisfactory. The entrance length is found to be increasing with the increase of Reynolds and Knudsen numbers. A correlation for hydrodynamic development length as a function of Knudsen and Reynolds numbers was obtained by using the data extracted from LBM simulations performed in this study.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44822312","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}
Pub Date : 2023-05-22DOI: 10.18186/thermal.1300847
A. Paul, Jintu MANI NATH, Tusar KANTI DAS
The thermal aspects of 𝐶𝑢 − 𝐴𝑙2𝑂3/𝑤𝑎𝑡𝑒𝑟 hybrid nanofluid in a porous medium across a ver-tically stretched cylinder with the incorporation of heat sink/source impact are investigated in this numerical study. A magnetic field along the transverse direction of the stretching cylinder and the thermal buoyancy effect is considered in the flow problem. A pertinent similarity vari-able has been employed to simplify the boundary layer equations which govern the flow and convert the coupled nonlinear partial differential equations into a set of non-linear ordinary differential equations. The numerical results are computed using the 3-stage Lobatto IIIa tech-nique, Bvp4c. The impacts of non- dimensional parameters, including Prandtl number, heat source/sink parameter, magnetic parameter, porosity parameter, curvature parameter, ther-mal stratification parameter, and thermal buoyancy parameter on the velocity curve, thermal curve, skin-friction coefficient, and Nusselt number, are illustrated graphically and numeri-cally portrayed in tables. The important results demonstrate that hybrid nanofluids are more thermally conductive than nanofluids. Therefore, the hybrid nanofluid has a considerable im-pact on improving thermal developments. It has been found that the absolute skin friction of the hybrid nanofluid is up to 31% higher compared to the nanofluid. The heat transport rate of the hybrid nanofluid is 7.5% enhanced in comparison to the nanofluid. The influence of heat stratification of the hybrid nanofluid flow is appreciably significant.
{"title":"An investigation of the MHD Cu-Al2O3/H2O hybrid-nanofluid in a porous medium across a vertically stretching cylinder incorporating thermal stratification impact","authors":"A. Paul, Jintu MANI NATH, Tusar KANTI DAS","doi":"10.18186/thermal.1300847","DOIUrl":"https://doi.org/10.18186/thermal.1300847","url":null,"abstract":"The thermal aspects of 𝐶𝑢 − 𝐴𝑙2𝑂3/𝑤𝑎𝑡𝑒𝑟 hybrid nanofluid in a porous medium across a ver-tically stretched cylinder with the incorporation of heat sink/source impact are investigated in this numerical study. A magnetic field along the transverse direction of the stretching cylinder and the thermal buoyancy effect is considered in the flow problem. A pertinent similarity vari-able has been employed to simplify the boundary layer equations which govern the flow and convert the coupled nonlinear partial differential equations into a set of non-linear ordinary differential equations. The numerical results are computed using the 3-stage Lobatto IIIa tech-nique, Bvp4c. The impacts of non- dimensional parameters, including Prandtl number, heat source/sink parameter, magnetic parameter, porosity parameter, curvature parameter, ther-mal stratification parameter, and thermal buoyancy parameter on the velocity curve, thermal curve, skin-friction coefficient, and Nusselt number, are illustrated graphically and numeri-cally portrayed in tables. The important results demonstrate that hybrid nanofluids are more thermally conductive than nanofluids. Therefore, the hybrid nanofluid has a considerable im-pact on improving thermal developments. It has been found that the absolute skin friction of the hybrid nanofluid is up to 31% higher compared to the nanofluid. The heat transport rate of the hybrid nanofluid is 7.5% enhanced in comparison to the nanofluid. The influence of heat stratification of the hybrid nanofluid flow is appreciably significant.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47632938","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}
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