Applied Thermal Engineering最新文献_第9页

Thermal-electrical-linked analysis of a thermal battery powering a guided weapon system

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125737

Jin Beom Kim , Eun Hye Bae , Hyun Jun Kim , Sang Jin Lee , Il Seouk Park , Sung Yeol Kim

Thermal management of a thermal battery is critical to ensure the robust operation of guided weapon systems. The electrical performance of the thermal battery is highly sensitive to changes in battery temperature during operation; the battery resistance increases significantly at low temperatures and the discharge capacity can be significantly reduced at excessively high temperatures. However, the thermal management and electrical performance of thermal batteries have been studied independently without linking them. In this study, a thermal-electrical-linked analysis platform was developed to predict the internal temperature variation and the resulting voltage variation of a thermal battery. The parameters of the Thevenin equivalent circuit model (TECM) as a function of temperature, depth of discharge (DoD), and applied current were obtained from a discharge test conducted on a unit cell. The temperature changes of the electrodes and electrolyte in unit cells were traced during activation and discharge. Based on the simulation temperatures, the thermal stability of the battery was analyzed considering the melting point of each component, and subsequently, the time required for activation and reaching the cut-off voltage was evaluated according to the operating temperature and discharge rate.

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引用次数: 0

System integration and performance analysis of solid oxide fuel cell-inverted gas turbine hybrid system

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125730

Yongyi Li , Jiaxin Ding , Haibo Sun , Guoqiang Zhang , Rongrong Zhai , Enhui Sun , Ligang Wang , Lei Zhang

Solid oxide fuel cell systems often face significant challenges in recovering high-quality exhaust heat and require carbon capture when utilizing carbon-based fuels. In this study, we integrate solid oxide fuel cell with an inverted gas turbine to effectively recover exhaust heat and achieve efficient carbon capture through oxy-fuel combustion in the afterburner. To address the issue of excessively high turbine inlet temperatures caused by oxy-fuel combustion, this paper proposes an innovative approach involving steam or carbon dioxide injection to regulate combustion temperatures. Using rigorous theoretical analysis and process modeling, multiple hybrid system configurations are developed and assessed for thermal integration through pinch point analysis. Energy and exergy analyses are employed to compare system performance and investigate the impact of the fuel utilization factor. The results indicate that steam/CO₂ injection effectively controls combustion temperatures, enhances energy recovery, and significantly increases waste heat recovery capacity. Notably, the oxy-fuel combustion system achieves exceptional performance, with a peak gross efficiency of 75.54 %, an output power of 185.18 kW, and an exergy efficiency of 63.52 % at a fuel utilization factor of 0.85.

{"title":"System integration and performance analysis of solid oxide fuel cell-inverted gas turbine hybrid system","authors":"Yongyi Li , Jiaxin Ding , Haibo Sun , Guoqiang Zhang , Rongrong Zhai , Enhui Sun , Ligang Wang , Lei Zhang","doi":"10.1016/j.applthermaleng.2025.125730","DOIUrl":"10.1016/j.applthermaleng.2025.125730","url":null,"abstract":"<div><div>Solid oxide fuel cell systems often face significant challenges in recovering high-quality exhaust heat and require carbon capture when utilizing carbon-based fuels. In this study, we integrate solid oxide fuel cell with an inverted gas turbine to effectively recover exhaust heat and achieve efficient carbon capture through oxy-fuel combustion in the afterburner. To address the issue of excessively high turbine inlet temperatures caused by oxy-fuel combustion, this paper proposes an innovative approach involving steam or carbon dioxide injection to regulate combustion temperatures. Using rigorous theoretical analysis and process modeling, multiple hybrid system configurations are developed and assessed for thermal integration through pinch point analysis. Energy and exergy analyses are employed to compare system performance and investigate the impact of the fuel utilization factor. The results indicate that steam/CO<sub>2</sub> injection effectively controls combustion temperatures, enhances energy recovery, and significantly increases waste heat recovery capacity. Notably, the oxy-fuel combustion system achieves exceptional performance, with a peak gross efficiency of 75.54 %, an output power of 185.18 kW, and an exergy efficiency of 63.52 % at a fuel utilization factor of 0.85.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"267 ","pages":"Article 125730"},"PeriodicalIF":6.1,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143173613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Meta-analysis of compartment fires: Exploring extensive experimental datasets with heat release rate in focus

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125733

Mohammad Javad Moradi, Hamzeh Hajiloo

This study reviews and analyzes 112 compartment fire tests to provide insights into fire behavior in realistic scenarios. The complex nature of compartment fire dynamics is emphasized by the significant variability in the collected data, which currently poses challenges for the development of engineering tools based on physical models. The results indicate that fuel load density alone does not fully account for fire hazard due to the impact of other factors on the maximum heat release rate (HRR) while higher compartment shape factor, defined as the ratio of total area (A_T) to floor area (A_F), result in reduced HRR due to greater heat loss and ventilation limitations. In the fire’s growth phase, effective removal of hot gases through openings can slow fire growth by reducing thermal feedback. In addition, increased fuel load density and furniture fuels, containing high calorific materials, shortens the time required to reach maximum HRR and prolongs post-flashover duration; reduced opening factors delay peak HRR time and extend post-flashover durations. It can be concluded that effective fire safety design necessitates considering the interconnection of all parameters for accurate predictive modeling.

{"title":"Meta-analysis of compartment fires: Exploring extensive experimental datasets with heat release rate in focus","authors":"Mohammad Javad Moradi, Hamzeh Hajiloo","doi":"10.1016/j.applthermaleng.2025.125733","DOIUrl":"10.1016/j.applthermaleng.2025.125733","url":null,"abstract":"<div><div>This study reviews and analyzes 112 compartment fire tests to provide insights into fire behavior in realistic scenarios. The complex nature of compartment fire dynamics is emphasized by the significant variability in the collected data, which currently poses challenges for the development of engineering tools based on physical models. The results indicate that fuel load density alone does not fully account for fire hazard due to the impact of other factors on the maximum heat release rate (HRR) while higher compartment shape factor, defined as the ratio of total area (A<sub>T</sub>) to floor area (A<sub>F</sub>), result in reduced HRR due to greater heat loss and ventilation limitations. In the fire’s growth phase, effective removal of hot gases through openings can slow fire growth by reducing thermal feedback. In addition, increased fuel load density and furniture fuels, containing high calorific materials, shortens the time required to reach maximum HRR and prolongs post-flashover duration; reduced opening factors delay peak HRR time and extend post-flashover durations. It can be concluded that effective fire safety design necessitates considering the interconnection of all parameters for accurate predictive modeling.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"266 ","pages":"Article 125733"},"PeriodicalIF":6.1,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143170066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Two-way coupled CFD-DEM model of a Disc-Shaped fluidized sorption reactor operating at low-pressure regimes

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125600

Marcin Sosnowski , Jaroslaw Krzywanski , Karolina Grabowska , Anna Zylka , Anna Kulakowska , Dorian Skrobek , Maciej Szudarek

The depletion of fossil fuels and increased greenhouse gas emissions are crucial factors forcing innovation in various branches of industry and life. In the 21st century, air conditioning is becoming a necessity for well-being and health. Therefore, adsorption cooling technology constitutes a very promising alternative to energy-consuming and environmentally hazardous vapour compression cooling. The main challenge in the wider popularization of adsorption technology lies in intensifying heat and mass transfer within the sorption reactor. Therefore, the paper presents different sorption reactor concepts proposed by the authors to solve the aforementioned issue. The main parameters influencing heat and mass transfer for each of the presented sorption reactor concepts were calculated using the computational fluid dynamics code adapted by the authors to capture the specific phenomenon occurring in the sorption reactor. The novelty presented in the paper is the application of a newly developed model that combines computational fluid dynamics and discrete element modelling to capture the specificity of the fluidized sorption reactor. The developed numerical model is validated against experimental data collected from the test stand dedicated to experimental research on innovative sorption reactors operating under various conditions. The presented results of numerical modelling using the developed approach, focusing on heat and momentum transfer during adsorbent particle fluidization within the sorption reactor under low-pressure regimes, are qualitatively coherent with experimental data, and their quantitative error does not exceed 0.98 °C (2.2 %) in the case of adsorbent temperature, 84 Pa (4.2 %) and 35 Pa (1.3 %) in the case of sorption chamber (upper tank) and evaporator (lower tank) pressure, respectively. The research allowed intensifying the heat and mass transfer in the sorption reactor and, in consequence, significantly contributed to the development and popularization of adsorption cooling technology and R&D in this area.

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引用次数: 0

Exergy, economic, and environmental impact of a flat plate solar collector with Al2O3-CuO/Water hybrid nanofluid: Experimental study

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125640

Sayantan Mukherjee , Drashti Shah , Paritosh Chaudhuri , Purna Chandra Mishra

The growing demand for efficient and sustainable energy solutions has intensified research on improving the performance of solar thermal systems. The viability of a flat plate solar collector was carefully explored. Water and Al₂O₃-CuO (50:50)/Water hybrid nanofluid were used as working fluids and their results were compared. The outlet temperature, energy efficiency, exergy efficiency, and entropy generation were investigated by varying the nanoparticle concentration from 0.01 to 0.05 mass% and by changing the inlet mass flow from 0.006 to 0.015 kg/s. Experimental measurements were taken under an average solar irradiation of 912.26 W/m².Peak values of energy efficiency and exergy efficiency were seen at 72.12 % and 3.01 %, respectively at 0.03 mass% and 0.015 kg/s flow rate. The hybrid nanofluid showed lowest entropy generation of 1.45 W/K and highest exergy destruction of 425.83 W at same concentration and flow rate. The hybrid nanofluid provided better efficiency, lower entropy generation and enhanced exergy reduction compared to water. The exergetic improvement potential was lowered to 3.58 % with the application of hybrid nanofluid. Economically, using the nanofluid could reduce collector size by 30.51 %. Sustainability assessments indicated an enhancement in the exergetic sustainability index up to 1.03 and a reduced environmental impact to 0.971 at 0.03 mass%, compared to water’s highest sustainability index of 1.019 and environmental impact of 0.99. Finally, enviroeconomic analysis reveals that hybrid nanofluid utilization can reduce the CO₂ mitigation and its cost up to 44 % based on energy utilization and 50 % based on exergy utilization compared to basefluid. The study recommends the use of Al₂O₃-CuO/Water nanofluids for solar collectors, highlighting their superior thermo-economic and enviroeconomic performances, sustainability and reduced environmental impact compared to conventional water-based systems.

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引用次数: 0

Experimental and numerical analysis on influence of air staging in a tangential flow burner for pure ammonia combustion

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125580

M. Srinivasarao , Sudarshan Kumar , Bok Jik Lee , Binod R. Giri , Krishna P. Shrestha , V. Mahendra Reddy

The combustion of pure ammonia has garnered significant attention due to the challenges involved in stabilizing flame. This study investigates pure ammonia flames using an innovative staged burner, with experiments conducted across three burner configurations: 2-stage, 3-stage, and 4-stage setups. In addition to the experimental work, comprehensive large eddy simulations (LES) are performed to assess the effects of thermal intensities, global equivalence ratios, and staging on pure ammonia flames. A wide flame stability range, with equivalence ratio spanning from 0.5 to 1.2, is achieved while maintaining minimal NO emissions and nearly zero ammonia slip. Key factors such as mixing, preheating temperatures, and local oxygen concentrations are found to play crucial roles in pure ammonia flame stabilization. For lower energy inputs, the 2-stage configuration exhibits optimal combustion performance with minimal NOx emissions (4.12 PPM/kW) and no ammonia slip. In contrast, the 4-stage configuration yields the lowest NOx emissions, reaching 0.8 PPM/kW. Furthermore, under comparable thermal intensities, variations in local oxygen concentrations significantly influenced NOx emissions, with the lowest NOx levels (143 PPM) observed in the 4-stage setup under stoichiometric conditions. At high thermal inputs with the 2-stage configuration, notable levels of N and NH species are identified at burner’s exit, contributing to reduced exit temperatures. Overall, the 4-stage configuration at high thermal inputs achieves the lowest NO flow rates (0.34 g/kW·hr), eliminates ammonia slip, and minimizes the N and NH radical species at the burner’s exit.

{"title":"Experimental and numerical analysis on influence of air staging in a tangential flow burner for pure ammonia combustion","authors":"M. Srinivasarao , Sudarshan Kumar , Bok Jik Lee , Binod R. Giri , Krishna P. Shrestha , V. Mahendra Reddy","doi":"10.1016/j.applthermaleng.2025.125580","DOIUrl":"10.1016/j.applthermaleng.2025.125580","url":null,"abstract":"<div><div>The combustion of pure ammonia has garnered significant attention due to the challenges involved in stabilizing flame. This study investigates pure ammonia flames using an innovative staged burner, with experiments conducted across three burner configurations: 2-stage, 3-stage, and 4-stage setups. In addition to the experimental work, comprehensive large eddy simulations (LES) are performed to assess the effects of thermal intensities, global equivalence ratios, and staging on pure ammonia flames. A wide flame stability range, with equivalence ratio spanning from 0.5 to 1.2, is achieved while maintaining minimal NO emissions and nearly zero ammonia slip. Key factors such as mixing, preheating temperatures, and local oxygen concentrations are found to play crucial roles in pure ammonia flame stabilization. For lower energy inputs, the 2-stage configuration exhibits optimal combustion performance with minimal NOx emissions (4.12 PPM/kW) and no ammonia slip. In contrast, the 4-stage configuration yields the lowest NOx emissions, reaching 0.8 PPM/kW. Furthermore, under comparable thermal intensities, variations in local oxygen concentrations significantly influenced NOx emissions, with the lowest NOx levels (143 PPM) observed in the 4-stage setup under stoichiometric conditions. At high thermal inputs with the 2-stage configuration, notable levels of N and NH species are identified at burner’s exit, contributing to reduced exit temperatures. Overall, the 4-stage configuration at high thermal inputs achieves the lowest NO flow rates (0.34 g/kW·hr), eliminates ammonia slip, and minimizes the N and NH radical species at the burner’s exit.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"266 ","pages":"Article 125580"},"PeriodicalIF":6.1,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143168623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Revealing baffle-enhanced heat transfer mechanism in an indirectly heated rotary kiln by discrete element method modeling

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125452

Fenglei Qi , Chao Zhang , Hao Cai , Zishuo Lin , Rui Diao , Xiaohao Liu , Dongxu Yan , Long-jin Jiang , Peiyong Ma

Baffles are often configured in indirectly heated rotary kilns in order to improve their performances on transferring heat to the particle bulk that is processed in the equipment. However, design of baffles still mainly depends on the empirical knowledge due to insufficient development of relationships revealing the influences of baffle configurations on the heat transfer coefficient. In this research, the heat transfer process in a rotary kiln with straight baffles was simulated by an in-house discrete element method and the impacting mechanism of baffles on the heat transfer between the rotary kiln shell and the particles was explored. The result suggests that installing baffles is capable of improving the contact surface area between the kiln shell and the particle bed, which is a dominant factor for the enhanced heat transfer performance. Baffle parameters including the baffle number and the baffle length have significant influences on the uniformity of the particle bed temperature distribution by directly affecting the particle mixing process. When the filling level is 25%, configuration of 8 baffles with a length of

5 / 9 H_{b}

is determined to be an optimal configuration with

H_{b}

being the static bed depth. The additional heat transfer area supplied by the baffle structure is also favorable for reducing the thermal time constant and its contribution takes approximately 20% in the optimized configuration.

{"title":"Revealing baffle-enhanced heat transfer mechanism in an indirectly heated rotary kiln by discrete element method modeling","authors":"Fenglei Qi , Chao Zhang , Hao Cai , Zishuo Lin , Rui Diao , Xiaohao Liu , Dongxu Yan , Long-jin Jiang , Peiyong Ma","doi":"10.1016/j.applthermaleng.2025.125452","DOIUrl":"10.1016/j.applthermaleng.2025.125452","url":null,"abstract":"<div><div>Baffles are often configured in indirectly heated rotary kilns in order to improve their performances on transferring heat to the particle bulk that is processed in the equipment. However, design of baffles still mainly depends on the empirical knowledge due to insufficient development of relationships revealing the influences of baffle configurations on the heat transfer coefficient. In this research, the heat transfer process in a rotary kiln with straight baffles was simulated by an in-house discrete element method and the impacting mechanism of baffles on the heat transfer between the rotary kiln shell and the particles was explored. The result suggests that installing baffles is capable of improving the contact surface area between the kiln shell and the particle bed, which is a dominant factor for the enhanced heat transfer performance. Baffle parameters including the baffle number and the baffle length have significant influences on the uniformity of the particle bed temperature distribution by directly affecting the particle mixing process. When the filling level is 25%, configuration of 8 baffles with a length of <span><math><mrow><mn>5</mn><mo>/</mo><mn>9</mn><msub><mrow><mi>H</mi></mrow><mrow><mi>b</mi></mrow></msub></mrow></math></span> is determined to be an optimal configuration with <span><math><msub><mrow><mi>H</mi></mrow><mrow><mi>b</mi></mrow></msub></math></span> being the static bed depth. The additional heat transfer area supplied by the baffle structure is also favorable for reducing the thermal time constant and its contribution takes approximately 20% in the optimized configuration.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"266 ","pages":"Article 125452"},"PeriodicalIF":6.1,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143170068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Visualization of vapor–liquid interface and optimization in vapor grooves of loop heat pipe

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125724

Zhou Xue , Hua Lingji , Shao Bo , Li Nanxi , Jiang Zhenhua , Lu Yan

Loop heat pipes (LHPs), utilizing the capillary force to circulate working fluid internally, have been widely employed as an efficient thermal management device in both aerospace industries and household technologies. Previous studies have proposed various optimization methods for LHPs and have succeeded in improving the device efficiency, while there still exist some difficult problems in dispute. A disagreement is on the optimal groove size and such inconsistency can be owing to the common neglect on the influence imposed by the changing vapor–liquid interface. In this work, therefore, a three-dimensional numerical simulation model and a visualization experiment were used to simultaneously investigate the vapor–liquid distribution and the thermal efficiency of the LHPs with different groove dimensions. The liquid film in the vapor groove gradually attenuates and retracts into the wick as the ratio of the depth and width of vapor groove (

β

) increases. The optimal thermal performance is achieved once the liquid interface coincides with the solid interface, namely, neither well above the wick surface nor beneath it, which corresponds to an optimal

β

value. Based on the experimental and numerical studies, such optimal value is around 1 over a wider range of heat loads. On the other hand, the lower the ratio of the width for grooves and fins (

η

), the less thermal resistance there is from the wall to the vapor–liquid interface, and thus the lower the temperature of the evaporator. The suitable range of

η

is within 0.7–0.9 exhibiting no clear dependency on the vapor–liquid distribution.

{"title":"Visualization of vapor–liquid interface and optimization in vapor grooves of loop heat pipe","authors":"Zhou Xue , Hua Lingji , Shao Bo , Li Nanxi , Jiang Zhenhua , Lu Yan","doi":"10.1016/j.applthermaleng.2025.125724","DOIUrl":"10.1016/j.applthermaleng.2025.125724","url":null,"abstract":"<div><div>Loop heat pipes (LHPs), utilizing the capillary force to circulate working fluid internally, have been widely employed as an efficient thermal management device in both aerospace industries and household technologies. Previous studies have proposed various optimization methods for LHPs and have succeeded in improving the device efficiency, while there still exist some difficult problems in dispute. A disagreement is on the optimal groove size and such inconsistency can be owing to the common neglect on the influence imposed by the changing vapor–liquid interface. In this work, therefore, a three-dimensional numerical simulation model and a visualization experiment were used to simultaneously investigate the vapor–liquid distribution and the thermal efficiency of the LHPs with different groove dimensions. The liquid film in the vapor groove gradually attenuates and retracts into the wick as the ratio of the depth and width of vapor groove (<span><math><mi>β</mi></math></span>) increases. The optimal thermal performance is achieved once the liquid interface coincides with the solid interface, namely, neither well above the wick surface nor beneath it, which corresponds to an optimal <span><math><mi>β</mi></math></span> value. Based on the experimental and numerical studies, such optimal value is around 1 over a wider range of heat loads. On the other hand, the lower the ratio of the width for grooves and fins (<span><math><mi>η</mi></math></span>), the less thermal resistance there is from the wall to the vapor–liquid interface, and thus the lower the temperature of the evaporator. The suitable range of <span><math><mi>η</mi></math></span> is within 0.7–0.9 exhibiting no clear dependency on the vapor–liquid distribution.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"267 ","pages":"Article 125724"},"PeriodicalIF":6.1,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143171996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Technoeconomic assessment of a solar-driven adsorption-based space conditioning system for low-energy multi-unit residential buildings in canada

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125739

Colin Ward, Jean Duquette, Cynthia A. Cruickshank

Building energy demands and associated greenhouse gas emissions are increasing in Canada. A potential pathway to counteract this trend involves moving away from carbon intensive fossil fuel and electricity driven space conditioning technologies like furnaces and vapour compression air conditioners towards more sustainable solar heating and cooling technologies. This study evaluates the technoeconomic and environmental performance of a solar-driven adsorption-based system used to meet the space conditioning and domestic hot water demands of a low-energy multi-unit residential building in Canada. A transient numerical model of the building and proposed system is developed in the TRNSYS environment. The following two reference systems are also modeled for comparison: 1) a modern system that uses unit-level mini-split heat pumps for space heating and cooling, and a centralized electric domestic hot water tank for water heating; and 2) a centralized system that uses natural gas for space and water heating, and a vapour compression chiller for space cooling. Results from annual simulations in 12 Canadian locations show that the proposed system can achieve solar fractions greater than 0.8 in certain areas (e.g., the cities of Winnipeg and Ottawa) and can reduce annual greenhouse gas emissions by up to 62.7% and 99.8% (in the city of Winnipeg) relative to the all-electric unit-level heat pump and centralized natural gas reference systems, respectively. While the levelized cost of energy for the proposed system is high, a compelling economic argument can be made in jurisdictions with fossil fuel dependent electrical grids.

{"title":"Technoeconomic assessment of a solar-driven adsorption-based space conditioning system for low-energy multi-unit residential buildings in canada","authors":"Colin Ward, Jean Duquette, Cynthia A. Cruickshank","doi":"10.1016/j.applthermaleng.2025.125739","DOIUrl":"10.1016/j.applthermaleng.2025.125739","url":null,"abstract":"<div><div>Building energy demands and associated greenhouse gas emissions are increasing in Canada. A potential pathway to counteract this trend involves moving away from carbon intensive fossil fuel and electricity driven space conditioning technologies like furnaces and vapour compression air conditioners towards more sustainable solar heating and cooling technologies. This study evaluates the technoeconomic and environmental performance of a solar-driven adsorption-based system used to meet the space conditioning and domestic hot water demands of a low-energy multi-unit residential building in Canada. A transient numerical model of the building and proposed system is developed in the TRNSYS environment. The following two reference systems are also modeled for comparison: 1) a modern system that uses unit-level mini-split heat pumps for space heating and cooling, and a centralized electric domestic hot water tank for water heating; and 2) a centralized system that uses natural gas for space and water heating, and a vapour compression chiller for space cooling. Results from annual simulations in 12 Canadian locations show that the proposed system can achieve solar fractions greater than 0.8 in certain areas (<em>e.g.,</em> the cities of Winnipeg and Ottawa) and can reduce annual greenhouse gas emissions by up to 62.7% and 99.8% (in the city of Winnipeg) relative to the all-electric unit-level heat pump and centralized natural gas reference systems, respectively. While the levelized cost of energy for the proposed system is high, a compelling economic argument can be made in jurisdictions with fossil fuel dependent electrical grids.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"267 ","pages":"Article 125739"},"PeriodicalIF":6.1,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143173154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Prediction-focused machine learning for performance adaptation of aero gas turbines through steady-state and transient simulation

IF 6.1 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2025-01-24 DOI: 10.1016/j.applthermaleng.2025.125732

Sangjo Kim

Performance adaptation is a method that enhances the accuracy of aero gas turbine performance models through the use of measurement data, and is valuable for applications such as control, operational optimization, and diagnostics. In traditional methods, adaptation factors are derived using physical models and numerical analyses, but these approaches are computationally intensive and time-consuming. This study introduces a performance adaptation method based on prediction-focused machine learning for both steady-state and transient operation, an approach that offers significant efficiency and accuracy improvements over conventional techniques. Using a feedforward neural network, component adaptation factors are determined and used to refine the engine performance in the steady state, while correction factors are used to adjust the predictions under transient conditions, thereby enabling real-time adaptability. This integrated method minimizes prediction errors across the most critical performance parameters. For example, the average absolute errors are reduced to 0.14 % for the total temperature at the high-pressure turbine exit, 0.38 % for the fan pressure ratio, 0.15 % for the low-pressure shaft speed, and 1.11 % for the engine net thrust. These results demonstrate not only the precision of the proposed approach but also its practical advantages in terms of reducing computational costs and improving adaptability. This study addresses the limitations of traditional performance adaptation techniques, and a scalable and efficient framework is presented that significantly enhances the accuracy of aero gas turbine performance models, thus paving the way for more reliable and responsive engine modeling in both research and industrial applications.

{"title":"Prediction-focused machine learning for performance adaptation of aero gas turbines through steady-state and transient simulation","authors":"Sangjo Kim","doi":"10.1016/j.applthermaleng.2025.125732","DOIUrl":"10.1016/j.applthermaleng.2025.125732","url":null,"abstract":"<div><div>Performance adaptation is a method that enhances the accuracy of aero gas turbine performance models through the use of measurement data, and is valuable for applications such as control, operational optimization, and diagnostics. In traditional methods, adaptation factors are derived using physical models and numerical analyses, but these approaches are computationally intensive and time-consuming. This study introduces a performance adaptation method based on prediction-focused machine learning for both steady-state and transient operation, an approach that offers significant efficiency and accuracy improvements over conventional techniques. Using a feedforward neural network, component adaptation factors are determined and used to refine the engine performance in the steady state, while correction factors are used to adjust the predictions under transient conditions, thereby enabling real-time adaptability. This integrated method minimizes prediction errors across the most critical performance parameters. For example, the average absolute errors are reduced to 0.14 % for the total temperature at the high-pressure turbine exit, 0.38 % for the fan pressure ratio, 0.15 % for the low-pressure shaft speed, and 1.11 % for the engine net thrust. These results demonstrate not only the precision of the proposed approach but also its practical advantages in terms of reducing computational costs and improving adaptability. This study addresses the limitations of traditional performance adaptation techniques, and a scalable and efficient framework is presented that significantly enhances the accuracy of aero gas turbine performance models, thus paving the way for more reliable and responsive engine modeling in both research and industrial applications.</div></div>","PeriodicalId":8201,"journal":{"name":"Applied Thermal Engineering","volume":"267 ","pages":"Article 125732"},"PeriodicalIF":6.1,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143172415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0