Pub Date : 2024-05-17DOI: 10.37934/arfmts.117.1.6070
Nik Kechik Mujahidah Nik Abdul Rahman, Syamimi Saadon, Raja Eizzuddin Shah Raja Muhammad Azhan Shah, Abd Rahim Abu Talib, Ezanee Gires, Hanim Salleh, Nasser Abdellatif
Waste heat accounts for 20-50% of industrial energy use, with Southeast Asia processing 40 million tonnes of oil equivalent. Heat losses especially in engines can reduce efficiency, leading to extensive studies to reduce heat loss and improve thermal performance. Heat recovery systems are being studied for recovering lower-grade energy, but not many of them are suitable and economically effective for low temperature waste heat. The objectives of this study are to develop low thermal conductivity agricultural-based material for thermal insulation and investigate the agricultural-based materials' impact on heat transfer rate. The agricultural-based materials that were used in this experiment were coconut husk and kenaf fibre due to their practically low thermal conductivity. The specimens were prepared using two different methods which were needle felting method and fibre-resin blending method. The experiment revealed that coconut husk fibre reinforced with resin (CHER) has the lowest thermal conductivity value of 0.0410 W/m.K and the lowest overall heat transfer rate of 2.85 W, making it an ideal thermal insulation material to be used for low-temperature applications.
{"title":"Thermal Performance Study on Coconut Husk and Kenaf Fibre as Thermal Insulation Materials","authors":"Nik Kechik Mujahidah Nik Abdul Rahman, Syamimi Saadon, Raja Eizzuddin Shah Raja Muhammad Azhan Shah, Abd Rahim Abu Talib, Ezanee Gires, Hanim Salleh, Nasser Abdellatif","doi":"10.37934/arfmts.117.1.6070","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.6070","url":null,"abstract":"Waste heat accounts for 20-50% of industrial energy use, with Southeast Asia processing 40 million tonnes of oil equivalent. Heat losses especially in engines can reduce efficiency, leading to extensive studies to reduce heat loss and improve thermal performance. Heat recovery systems are being studied for recovering lower-grade energy, but not many of them are suitable and economically effective for low temperature waste heat. The objectives of this study are to develop low thermal conductivity agricultural-based material for thermal insulation and investigate the agricultural-based materials' impact on heat transfer rate. The agricultural-based materials that were used in this experiment were coconut husk and kenaf fibre due to their practically low thermal conductivity. The specimens were prepared using two different methods which were needle felting method and fibre-resin blending method. The experiment revealed that coconut husk fibre reinforced with resin (CHER) has the lowest thermal conductivity value of 0.0410 W/m.K and the lowest overall heat transfer rate of 2.85 W, making it an ideal thermal insulation material to be used for low-temperature applications.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141127096","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}
Terminal synergetic control (TSC) is proposed as a control strategy for the temperature management of a plate heat exchanger. The controller is designed by incorporating a selected macro variable with a time-varying sliding surface. The primary objective is to maintain precise control over the outlet temperature of the cold water. To assess the convergence characteristics of the newly proposed TSC approach, the simulation results achieved using TSC featuring a time-varying macro variable are compared to those obtained from the conventional synergetic control (SC) method. With an appropriate macro variable, the simulation results indicate a notable improvement in the convergence rate provided by our designed TSC method, compared to the conventional one. The desirable property of control input, the chattering-free condition, achieved by both TSC and SC approaches emphasizes the advantage of the synergetic control-based techniques over the conventional sliding mode controller. In conclusion, synergetic control-based techniques offer superior potential solutions for nonlinear feedback control problems.
{"title":"Terminal Synergetic Control for Plate Heat Exchanger","authors":"Arsit Boonyaprapasorn, Sorn Simatrang, Suwat Kuntanapreeda, Parinya Sa Ngiamsunthorn, Tinnakorn Kumsaen, Thunyaseth Sethaput","doi":"10.37934/arfmts.117.1.189202","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.189202","url":null,"abstract":"Terminal synergetic control (TSC) is proposed as a control strategy for the temperature management of a plate heat exchanger. The controller is designed by incorporating a selected macro variable with a time-varying sliding surface. The primary objective is to maintain precise control over the outlet temperature of the cold water. To assess the convergence characteristics of the newly proposed TSC approach, the simulation results achieved using TSC featuring a time-varying macro variable are compared to those obtained from the conventional synergetic control (SC) method. With an appropriate macro variable, the simulation results indicate a notable improvement in the convergence rate provided by our designed TSC method, compared to the conventional one. The desirable property of control input, the chattering-free condition, achieved by both TSC and SC approaches emphasizes the advantage of the synergetic control-based techniques over the conventional sliding mode controller. In conclusion, synergetic control-based techniques offer superior potential solutions for nonlinear feedback control problems.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141126414","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 : 2024-05-17DOI: 10.37934/arfmts.117.1.8397
Muntadher Mohammed Ali Saeed, Hassanain Ghani Hameed, Hayder Azeez Neamah Diabil
Herein, the performance of a solar air heater (SAH) is experimentally investigated, utilising an array of tubes as the absorbent part. The study evaluates the impact of incorporating Al2O3-paraffin wax as a non-PCM storage medium in comparison to a traditional flat-plate solar air heater, specifically under Najaf-Iraq climate conditions. The SAH is positioned at an inclination of 32.1 degrees with respect to the horizon, allowing it to align optimally with the solar direction. The results reveal notable differences in thermal performance characteristics among the various models. The highest thermal efficiency values are observed for distinct configurations: the proposed model achieves about 55.2%, the wax-supported model reaches 55.9%, and the nano-PCM-reinforced model attains 57.7%, while the traditional model lags at 48.2%. Furthermore, an analysis of different air mass flow rates highlights a crucial finding. Specifically, an air mass flow rate of 0.01 kg/s results in a higher temperature exiting from the system compared to a flow rate of 0.02 kg/s. This is attributed to the extended interaction time between the passing air and the absorbing surface, facilitating enhanced heat exchange. Consequently, the system's thermal efficiency experiences an increase. The study underscores the superior thermal performance and efficiency of the tube array nano-PCM collector type under Najaf city-Iraq climate conditions.
{"title":"Experimental Investigation on Thermal Performance of Solar Air Heater using Nano-PCM","authors":"Muntadher Mohammed Ali Saeed, Hassanain Ghani Hameed, Hayder Azeez Neamah Diabil","doi":"10.37934/arfmts.117.1.8397","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.8397","url":null,"abstract":"Herein, the performance of a solar air heater (SAH) is experimentally investigated, utilising an array of tubes as the absorbent part. The study evaluates the impact of incorporating Al2O3-paraffin wax as a non-PCM storage medium in comparison to a traditional flat-plate solar air heater, specifically under Najaf-Iraq climate conditions. The SAH is positioned at an inclination of 32.1 degrees with respect to the horizon, allowing it to align optimally with the solar direction. The results reveal notable differences in thermal performance characteristics among the various models. The highest thermal efficiency values are observed for distinct configurations: the proposed model achieves about 55.2%, the wax-supported model reaches 55.9%, and the nano-PCM-reinforced model attains 57.7%, while the traditional model lags at 48.2%. Furthermore, an analysis of different air mass flow rates highlights a crucial finding. Specifically, an air mass flow rate of 0.01 kg/s results in a higher temperature exiting from the system compared to a flow rate of 0.02 kg/s. This is attributed to the extended interaction time between the passing air and the absorbing surface, facilitating enhanced heat exchange. Consequently, the system's thermal efficiency experiences an increase. The study underscores the superior thermal performance and efficiency of the tube array nano-PCM collector type under Najaf city-Iraq climate conditions.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141126967","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}
Among the measures to be taken to design and construct buildings with envelopes that are more energy-efficient, sustainable, and environmentally friendly is thermal insulation using a very wide range of insulating materials, either synthetic or of natural origin or derived from biomass. The present work represents a thermal and energy study aimed at improving the thermal comfort levels and energy requirements of a typical residential building located in the city of Al-Hoceima, Morocco. To this end, a series of numerical simulations were carried out using TRNSYS software to assess the impact of applying three bio-based insulation materials, namely hemp wool, wood fiber, and expanded cork, in the wall layer of the building. Different insulation scenarios were studied to make a choice that would ensure optimum comfort in the building with low energy demand. The results of this study show that insulating the roof with 8 cm of hemp wool contributes to energy savings of up to 36.7% and 35.2% for cooling and heating demand respectively. In thermal terms, improvements in the temperature inside the building have been achieved: in January, the maximum temperature recorded is 20.94°C, while in July, the maximum temperature is around 26.80°C.
{"title":"Impact of Insulation using Bio-sourced Materials on the Thermal and Energy Performance of a Typical Residential Building in Morocco","authors":"Hicham Kaddouri, Abderrahim Abidouche, Mohamed Saidi Hassani Alaoui, Ismael Driouch, Said Hamdaoui","doi":"10.37934/arfmts.117.1.4359","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.4359","url":null,"abstract":"Among the measures to be taken to design and construct buildings with envelopes that are more energy-efficient, sustainable, and environmentally friendly is thermal insulation using a very wide range of insulating materials, either synthetic or of natural origin or derived from biomass. The present work represents a thermal and energy study aimed at improving the thermal comfort levels and energy requirements of a typical residential building located in the city of Al-Hoceima, Morocco. To this end, a series of numerical simulations were carried out using TRNSYS software to assess the impact of applying three bio-based insulation materials, namely hemp wool, wood fiber, and expanded cork, in the wall layer of the building. Different insulation scenarios were studied to make a choice that would ensure optimum comfort in the building with low energy demand. The results of this study show that insulating the roof with 8 cm of hemp wool contributes to energy savings of up to 36.7% and 35.2% for cooling and heating demand respectively. In thermal terms, improvements in the temperature inside the building have been achieved: in January, the maximum temperature recorded is 20.94°C, while in July, the maximum temperature is around 26.80°C.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141126236","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 : 2024-05-17DOI: 10.37934/arfmts.117.1.118131
Widya Wijayanti, Purnami, Lilis Yuliati, Mega Nur Sasongko, Elvinda Sangkilang, Yafi Dwi Saputra, Rizky Kusumastuti
This study investigates the energy conversion process of biomass into solid fuel, focusing on hydrothermal carbonization as the chosen method. The aim of study is to produce char with a higher energy yield compared to conventional combustion and pyrolysis methods. By manipulating the holding time in the hydrothermal process, this research examines the energy yields and their relationship with the storage and release of energy, thus impacting the heating values of the resulting char. The study establishes the optimal processing time critical for energy savings in hydrothermal energy conversion. Using mahogany wood as the initial biomass at a pressure of 5 atm and T = 200°C, the experiment involved a 200 g biomass with a 1:4 biomass to water ratio. The holding times varied at intervals of 30, 60, 90, and 120 minutes, respectively. The results indicate a direct proportionality between energy yields and heating values. The highest heating value of char, recorded at 5560.9088 kcal/kg, was achieved at a holding time of 60 minutes, while the lowest value, 2911.501 kcal/kg, was observed at 30 minutes. This suggests that a 60-minute duration in the carbonization process yields maximum energy output. Proximate analysis further supports this, indicating elevated levels of fixed carbon and volatile matter in the hydrothermal process. Then, the comparative analysis demonstrates that the heating value of the char exceeds that of char produced by pyrolysis and even surpasses raw mahogany wood. This study highlights the efficiency of a 60-minute hydrothermal carbonization process in maximizing energy yield, emphasizing its potential in biomass energy conversion.
{"title":"A Study of the Holding Time Effect on Char Yield Production in Hydrothermal Carbonization Behavior","authors":"Widya Wijayanti, Purnami, Lilis Yuliati, Mega Nur Sasongko, Elvinda Sangkilang, Yafi Dwi Saputra, Rizky Kusumastuti","doi":"10.37934/arfmts.117.1.118131","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.118131","url":null,"abstract":"This study investigates the energy conversion process of biomass into solid fuel, focusing on hydrothermal carbonization as the chosen method. The aim of study is to produce char with a higher energy yield compared to conventional combustion and pyrolysis methods. By manipulating the holding time in the hydrothermal process, this research examines the energy yields and their relationship with the storage and release of energy, thus impacting the heating values of the resulting char. The study establishes the optimal processing time critical for energy savings in hydrothermal energy conversion. Using mahogany wood as the initial biomass at a pressure of 5 atm and T = 200°C, the experiment involved a 200 g biomass with a 1:4 biomass to water ratio. The holding times varied at intervals of 30, 60, 90, and 120 minutes, respectively. The results indicate a direct proportionality between energy yields and heating values. The highest heating value of char, recorded at 5560.9088 kcal/kg, was achieved at a holding time of 60 minutes, while the lowest value, 2911.501 kcal/kg, was observed at 30 minutes. This suggests that a 60-minute duration in the carbonization process yields maximum energy output. Proximate analysis further supports this, indicating elevated levels of fixed carbon and volatile matter in the hydrothermal process. Then, the comparative analysis demonstrates that the heating value of the char exceeds that of char produced by pyrolysis and even surpasses raw mahogany wood. This study highlights the efficiency of a 60-minute hydrothermal carbonization process in maximizing energy yield, emphasizing its potential in biomass energy conversion.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141126049","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 : 2024-05-17DOI: 10.37934/arfmts.117.1.179188
Nadhum H. Safir, Zuradzman Mohamad Razlan, Shahriman Abu Bakar, Muhammmad Hussein Akbar Ali, Mohd Zulkifly Abdullah, Girrimuniswar Ramasamy, Rodhiyathul Ahyaa Akbar Ali
Working fluids play a crucial role in closed systems to ensure efficient performance, particularly in systems for heating, cooling, or power generation, where the heat transfer coefficient is pivotal. This study delves into the thermodynamic properties and stability of copper oxide (CuO) nanofluids as alternative working fluids in closed systems. Investigating colloidal suspensions of CuO nanoparticles, the research aims to enhance heat transfer efficiency. CuO nanoparticles, sized at 40nm and 80nm, were dispersed in base fluids like water, ethylene glycol, and oil sans surfactants. The study, divided into static and dynamic phases, examines key nanofluid properties including viscosity, thermal conductivity, specific heat, and heat transfer rate. Through methodologies such as KD2 Pro for thermal conductivity, rheometer for viscosity, and small heat exchanger for heat transfer rate analysis, the effects of volume concentration, temperature, and nanoparticle size on nanofluid performance were evaluated. Sedimentation analysis employed both quantitative (standard deviation calculations) and qualitative (sediment capture methods) approaches. The findings highlight the superior heat transfer rate of 40nm CuO nanofluid at 0.467% volume concentration which is 9.08 kJ/s, suggesting its potential to optimize system efficiency, particularly in heating, cooling, and power generation applications.
{"title":"Enhancing Closed System Efficiency through CuO Nanofluids: Investigating Thermophysical Properties and Heat Transfer Performance","authors":"Nadhum H. Safir, Zuradzman Mohamad Razlan, Shahriman Abu Bakar, Muhammmad Hussein Akbar Ali, Mohd Zulkifly Abdullah, Girrimuniswar Ramasamy, Rodhiyathul Ahyaa Akbar Ali","doi":"10.37934/arfmts.117.1.179188","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.179188","url":null,"abstract":"Working fluids play a crucial role in closed systems to ensure efficient performance, particularly in systems for heating, cooling, or power generation, where the heat transfer coefficient is pivotal. This study delves into the thermodynamic properties and stability of copper oxide (CuO) nanofluids as alternative working fluids in closed systems. Investigating colloidal suspensions of CuO nanoparticles, the research aims to enhance heat transfer efficiency. CuO nanoparticles, sized at 40nm and 80nm, were dispersed in base fluids like water, ethylene glycol, and oil sans surfactants. The study, divided into static and dynamic phases, examines key nanofluid properties including viscosity, thermal conductivity, specific heat, and heat transfer rate. Through methodologies such as KD2 Pro for thermal conductivity, rheometer for viscosity, and small heat exchanger for heat transfer rate analysis, the effects of volume concentration, temperature, and nanoparticle size on nanofluid performance were evaluated. Sedimentation analysis employed both quantitative (standard deviation calculations) and qualitative (sediment capture methods) approaches. The findings highlight the superior heat transfer rate of 40nm CuO nanofluid at 0.467% volume concentration which is 9.08 kJ/s, suggesting its potential to optimize system efficiency, particularly in heating, cooling, and power generation applications.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141125999","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 : 2024-05-17DOI: 10.37934/arfmts.117.1.164178
Kudzanayi Chiteka, Rajesh Arora, Christopher C. Enweremadu
This study analyses fixed and tracking solar photovoltaics and, solar thermal power. Performance in different locations was analysed for each configuration and technology using simulations based on a Typical Meteorological Year data. The study analysed a 25MWp solar photovoltaic and solar thermal power plants in each of the eleven selected locations in Zimbabwe. The performance of the solar photovoltaic and solar thermal power plants under different meteorological variables were assessed for all the selected locations. It was shown that different configurations together with different technologies have different conversion efficiencies. A high solar thermal conversion efficiency was found to be 18.718% in Gweru while it was 15.502% for solar photovoltaics in Mutare. The study also showed that highest insolation and clearness index values were found in Gweru. The average energy generated by the fixed photovoltaic collectors, tracking photovoltaic collectors and the Concentrating Solar Power plant were respectively 47.38GWh, 68.18GWh and 192.86GWh. There was a maximum percentage difference in the LCoE generated of 32.03% between the fixed PV collectors and the Concentrating Solar Power plant and a difference of 4.74% was realised between the tracking photovoltaics and Concentration Solar Power.
{"title":"Comparative Numerical Energy and Performance Analysis of Solar Photovoltaic and Solar Thermal Power Generation","authors":"Kudzanayi Chiteka, Rajesh Arora, Christopher C. Enweremadu","doi":"10.37934/arfmts.117.1.164178","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.164178","url":null,"abstract":"This study analyses fixed and tracking solar photovoltaics and, solar thermal power. Performance in different locations was analysed for each configuration and technology using simulations based on a Typical Meteorological Year data. The study analysed a 25MWp solar photovoltaic and solar thermal power plants in each of the eleven selected locations in Zimbabwe. The performance of the solar photovoltaic and solar thermal power plants under different meteorological variables were assessed for all the selected locations. It was shown that different configurations together with different technologies have different conversion efficiencies. A high solar thermal conversion efficiency was found to be 18.718% in Gweru while it was 15.502% for solar photovoltaics in Mutare. The study also showed that highest insolation and clearness index values were found in Gweru. The average energy generated by the fixed photovoltaic collectors, tracking photovoltaic collectors and the Concentrating Solar Power plant were respectively 47.38GWh, 68.18GWh and 192.86GWh. There was a maximum percentage difference in the LCoE generated of 32.03% between the fixed PV collectors and the Concentrating Solar Power plant and a difference of 4.74% was realised between the tracking photovoltaics and Concentration Solar Power.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141126225","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 : 2024-05-17DOI: 10.37934/arfmts.117.1.7182
Yudi Maulana, Bukhari Manshoor, Amir Khalid, Izzuddin Zaman, Djamal Hissein Didane, Reazul Haq Abdul Haq, Kamarul-Azhar Kamarudin, Syahreen Nurmutia, Abdul Rafeq Saleman, Rio Marco Rathje, Christin Rothe, Mohd Nizam Ibrahim
Noise emission is an essential issue for the aviation industry, as it harms health and induces various physiological responses. The noise generated by supersonic jets is very intense. It will cause fatigue and even damage the human hearing system in the surrounding area of jet operation. Besides, the experimental and prototyping cost for the jet model is prohibitive, and it is a vast project and process that takes a lot of time to run. The purpose of this study is to determine the sound propagation behaviours of a supersonic jet in the far-field region and to analyse the consequences of the velocity of a supersonic jet on sound propagation of supersonic jet by using computational fluid dynamics (CFD) and computational aeroacoustics (CAA) simulations. This study focused on the perspective of observing the distance of the receiver when receiving the sound propagation of a supersonic jet, the observed angle of the receiver when receiving the sound propagation of a supersonic jet, and the velocity of the supersonic jet. The CFD and CAA analyses were performed in transient state simulation and the 2-inch Acoustics Reference Nozzle (ARN2). The result shows that the overall SPL throughout the frequency is proportional to the jet velocity of the supersonic jet. However, the distance and angle of the receiver gave different results in sound propagation behaviour. The results also conclude that as the distance between the receiver and jet nozzle exit increases, the overall SPL trend will decrease throughout the frequency increase. As the vertical distance between the receiver and the axisymmetric line of the jet nozzle increases, the frequency of the receiver starts to observe will decrease.
{"title":"Analysis of Sound Propagation Behaviors for Supersonic Jet on Far Field Region by Computational Aero-Acoustics (CAA) Simulation","authors":"Yudi Maulana, Bukhari Manshoor, Amir Khalid, Izzuddin Zaman, Djamal Hissein Didane, Reazul Haq Abdul Haq, Kamarul-Azhar Kamarudin, Syahreen Nurmutia, Abdul Rafeq Saleman, Rio Marco Rathje, Christin Rothe, Mohd Nizam Ibrahim","doi":"10.37934/arfmts.117.1.7182","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.7182","url":null,"abstract":"Noise emission is an essential issue for the aviation industry, as it harms health and induces various physiological responses. The noise generated by supersonic jets is very intense. It will cause fatigue and even damage the human hearing system in the surrounding area of jet operation. Besides, the experimental and prototyping cost for the jet model is prohibitive, and it is a vast project and process that takes a lot of time to run. The purpose of this study is to determine the sound propagation behaviours of a supersonic jet in the far-field region and to analyse the consequences of the velocity of a supersonic jet on sound propagation of supersonic jet by using computational fluid dynamics (CFD) and computational aeroacoustics (CAA) simulations. This study focused on the perspective of observing the distance of the receiver when receiving the sound propagation of a supersonic jet, the observed angle of the receiver when receiving the sound propagation of a supersonic jet, and the velocity of the supersonic jet. The CFD and CAA analyses were performed in transient state simulation and the 2-inch Acoustics Reference Nozzle (ARN2). The result shows that the overall SPL throughout the frequency is proportional to the jet velocity of the supersonic jet. However, the distance and angle of the receiver gave different results in sound propagation behaviour. The results also conclude that as the distance between the receiver and jet nozzle exit increases, the overall SPL trend will decrease throughout the frequency increase. As the vertical distance between the receiver and the axisymmetric line of the jet nozzle increases, the frequency of the receiver starts to observe will decrease.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141126143","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 : 2024-05-17DOI: 10.37934/arfmts.117.1.203213
Nguyen Thi Ngoc Hoa, Tat-Hien Le, Le Doan Nhat Huy
Predict accurately resistance of the ship and flow around ship hull form is extremely important as these are input parameters for optimizing ship hull form, designing the ship propulsion system. This paper focuses on the numerical simulation of the flow around the Container Ship Fortune Freighter in calm water condition at different ship speeds by using CFD method. The results of impact of ship speed on components of ship resistance, wave patterns, volume fraction of air, the distribution of pressure, and wall shear stress on the ship's hull surface, as well as the nominal wake field are provided and analysed in this paper.
{"title":"Numerical Simulation Flow Around the Containership by using CFD Method","authors":"Nguyen Thi Ngoc Hoa, Tat-Hien Le, Le Doan Nhat Huy","doi":"10.37934/arfmts.117.1.203213","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.203213","url":null,"abstract":"Predict accurately resistance of the ship and flow around ship hull form is extremely important as these are input parameters for optimizing ship hull form, designing the ship propulsion system. This paper focuses on the numerical simulation of the flow around the Container Ship Fortune Freighter in calm water condition at different ship speeds by using CFD method. The results of impact of ship speed on components of ship resistance, wave patterns, volume fraction of air, the distribution of pressure, and wall shear stress on the ship's hull surface, as well as the nominal wake field are provided and analysed in this paper.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141126742","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 : 2024-05-17DOI: 10.37934/arfmts.117.1.143154
Ashish Shivkumar Utage, Kundlik Vitthal Mali, Heramb C. Phadake
This article presents experimental evaluation and comparative analysis of low GWP alternative refrigerants, namely HC-290 (propane), HC-1270 (propylene), HC/HC-1270 blend, and HFC-32 (difluoro methane) as drop-in replacements for HCFC-22 (Chloro difluoro methane) in a typical 1.5 TR capacity inverter operated split type air conditioner (SAC). The experimental setup consisted of retrofitting an original HCFC-22 test unit following the soft optimization of the SAC system for each alternative refrigerant, followed by testing under controlled operating conditions as per the IS 1391, Part-1 standard at the half capacity and the rated capacity of inverter SAC. The results obtained were compared against the baseline HCFC-22 test unit. The optimized SAC gave EERIS (Indian Seasonal Energy Efficiency Ratio) of 4.63 for HC-290, 4.71 for HC-1270 and 4.87 for HC-290/HC-1270 blend, respectively increased by 8.94 %, 10.82 % and 14.58 % compared to HCFC-22. HFC-32 delivered the maximum cooling capacity of 6.78 kW, 3.67 % higher than baseline unit at the rated capacity. HC-290/HC-1270 blend exhibited the lowest power consumption and discharge temperature amongst all the refrigerants considered. The charge of flammable refrigerants has been optimized below LFL satisfying EN378 standard for the safety of inverter SAC in domestic applications.
{"title":"Experimental and Theoretical Assessment of Inverter-Operated Split Air Conditioner with Low GWP Alternative Refrigerants","authors":"Ashish Shivkumar Utage, Kundlik Vitthal Mali, Heramb C. Phadake","doi":"10.37934/arfmts.117.1.143154","DOIUrl":"https://doi.org/10.37934/arfmts.117.1.143154","url":null,"abstract":"This article presents experimental evaluation and comparative analysis of low GWP alternative refrigerants, namely HC-290 (propane), HC-1270 (propylene), HC/HC-1270 blend, and HFC-32 (difluoro methane) as drop-in replacements for HCFC-22 (Chloro difluoro methane) in a typical 1.5 TR capacity inverter operated split type air conditioner (SAC). The experimental setup consisted of retrofitting an original HCFC-22 test unit following the soft optimization of the SAC system for each alternative refrigerant, followed by testing under controlled operating conditions as per the IS 1391, Part-1 standard at the half capacity and the rated capacity of inverter SAC. The results obtained were compared against the baseline HCFC-22 test unit. The optimized SAC gave EERIS (Indian Seasonal Energy Efficiency Ratio) of 4.63 for HC-290, 4.71 for HC-1270 and 4.87 for HC-290/HC-1270 blend, respectively increased by 8.94 %, 10.82 % and 14.58 % compared to HCFC-22. HFC-32 delivered the maximum cooling capacity of 6.78 kW, 3.67 % higher than baseline unit at the rated capacity. HC-290/HC-1270 blend exhibited the lowest power consumption and discharge temperature amongst all the refrigerants considered. The charge of flammable refrigerants has been optimized below LFL satisfying EN378 standard for the safety of inverter SAC in domestic applications.","PeriodicalId":37460,"journal":{"name":"Journal of Advanced Research in Fluid Mechanics and Thermal Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141126830","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}