The performance of air conditioning systems is highly dependent on the environmental conditions of the high pressure side, where heat is rejected to the environment. Air conditioning systems utilize dry cooling systems which often don’t provide adequate cooling during peak cooling periods, or wet cooling systems which consume a lot of water. In this study, a novel hybrid cooling system that can provide both wet and dry cooling was modelled in TRNSYS, and used to provide cooling to closed sorption air conditioning systems. The performance of these systems with the hybrid cooling system was compared to the performance of a standard vapor compression cooling system being cooled by a dry cooling system. The COPsol of the vapor compression cooling system exhibited a decrease of almost 26% during the summer period, whereas the COPsol of the sorption systems increased by around 30%. Similarly, the cooling capacity of the vapor compression cooling system dropped by almost 5%, and for the sorption systems, it increased by around 20% during the summer period.
{"title":"Performance Enhancement of Solar Air Conditioners Using Hybrid Heat Rejection System","authors":"A. Iqbal, Ali Al-Alili","doi":"10.1115/es2019-3930","DOIUrl":"https://doi.org/10.1115/es2019-3930","url":null,"abstract":"\u0000 The performance of air conditioning systems is highly dependent on the environmental conditions of the high pressure side, where heat is rejected to the environment. Air conditioning systems utilize dry cooling systems which often don’t provide adequate cooling during peak cooling periods, or wet cooling systems which consume a lot of water. In this study, a novel hybrid cooling system that can provide both wet and dry cooling was modelled in TRNSYS, and used to provide cooling to closed sorption air conditioning systems. The performance of these systems with the hybrid cooling system was compared to the performance of a standard vapor compression cooling system being cooled by a dry cooling system. The COPsol of the vapor compression cooling system exhibited a decrease of almost 26% during the summer period, whereas the COPsol of the sorption systems increased by around 30%. Similarly, the cooling capacity of the vapor compression cooling system dropped by almost 5%, and for the sorption systems, it increased by around 20% during the summer period.","PeriodicalId":219138,"journal":{"name":"ASME 2019 13th International Conference on Energy Sustainability","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124492128","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}
C. Ho, Sean Kinahan, Jesus D. Ortega, P. Vorobieff, A. Mammoli, Vanderlei Martins
Camera-based imaging methods were evaluated to quantify both particle and convective heat losses from the aperture of a high-temperature particle receiver. A bench-scale model of a field-tested on-sun particle receiver was built, and particle velocities and temperatures were recorded using the small-scale model. Particles heated to over 700 °C in a furnace were released from a slot aperture and allowed to fall through a region that was imaged by the cameras. Particle-image, particle-tracking, and image-correlation velocimetry methods were compared against one another to determine the best method to obtain particle velocities. A high-speed infrared camera was used to evaluate particle temperatures, and a model was developed to determine particle and convective heat losses. In addition, particle sampling instruments were deployed during on-sun field tests of the particle receiver to determine if small particles were being generated that can pose an inhalation hazard. Results showed that while there were some recordable emissions during the tests, the measured particle concentrations were much lower than the acceptable health standard of 15 mg/m3. Additional bench-scale tests were performed to quantify the formation of particles during continuous shaking and dropping of the particles. Continuous formation of small particles in two size ranges (< ∼1 microns and between ∼8–10 microns) were observed due to de-agglomeration and mechanical fracturing, respectively, during particle collisions.
{"title":"Characterization of Particle and Heat Losses From Falling Particle Receivers","authors":"C. Ho, Sean Kinahan, Jesus D. Ortega, P. Vorobieff, A. Mammoli, Vanderlei Martins","doi":"10.1115/es2019-3826","DOIUrl":"https://doi.org/10.1115/es2019-3826","url":null,"abstract":"\u0000 Camera-based imaging methods were evaluated to quantify both particle and convective heat losses from the aperture of a high-temperature particle receiver. A bench-scale model of a field-tested on-sun particle receiver was built, and particle velocities and temperatures were recorded using the small-scale model. Particles heated to over 700 °C in a furnace were released from a slot aperture and allowed to fall through a region that was imaged by the cameras. Particle-image, particle-tracking, and image-correlation velocimetry methods were compared against one another to determine the best method to obtain particle velocities. A high-speed infrared camera was used to evaluate particle temperatures, and a model was developed to determine particle and convective heat losses. In addition, particle sampling instruments were deployed during on-sun field tests of the particle receiver to determine if small particles were being generated that can pose an inhalation hazard. Results showed that while there were some recordable emissions during the tests, the measured particle concentrations were much lower than the acceptable health standard of 15 mg/m3. Additional bench-scale tests were performed to quantify the formation of particles during continuous shaking and dropping of the particles. Continuous formation of small particles in two size ranges (< ∼1 microns and between ∼8–10 microns) were observed due to de-agglomeration and mechanical fracturing, respectively, during particle collisions.","PeriodicalId":219138,"journal":{"name":"ASME 2019 13th International Conference on Energy Sustainability","volume":"2015 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129282440","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}
To reduce dependence on imported fossil fuels and develop indigenous biofuels, the Philippines enacted the Biofuels Act of 2006 which currently mandates a 10% by volume blend of 99.6% anhydrous bio-ethanol for commercially sold Unleaded and Premium gasolines. To urge a regulation review of the anhydrous requirement and examine the suitability for automotive use of hydrous bioethanol (HBE) blends, preliminary engine dynamometer tests at 1400–4400 rpm were conducted to measure specific fuel consumption (SFC) and power. In this study, HBE (95 % ethanol and 5% water by volume) produced from sweet sorghum using a locally-developed process, was blended volumetrically with three base gasoline fuels — Neat, Unleaded, and Premium. The four HBE blends tested were 10% and 20% with Neat gasoline, 20% with Unleaded gasoline, and 20% with Premium gasoline. For blends with Neat gasoline, the SFC of the 10%HBE blend was comparable with to slightly higher than Neat gasoline. The SFC of the 20%HBE blend was comparable with Neat gasoline up to 2800 rpm and lower beyond this speed thus being better overall than the 10%HBE blend. Compared to their respective commercial base fuels, the HBE-Unleaded blend showed lower SFC while the HBE-Premium blend yielded slightly higher SFC over most of the engine speed range. Between commercial fuel blends, the HBE-Unleaded blend gave better SFC than the HBE-Premium blend. Power was practically similar for the fuels tested. No engine operational problems and fuel blend phase separation were encountered during the tests. This preliminary study indicated the suitability of and possible optimum hydrous bio-ethanol blends for automotive use under Philippine conditions.
{"title":"Performance Characteristics of Philippine Hydrous Ethanol-Gasoline Blends: Preliminary Findings","authors":"J. Yu, E. Quiros","doi":"10.1115/es2019-3824","DOIUrl":"https://doi.org/10.1115/es2019-3824","url":null,"abstract":"\u0000 To reduce dependence on imported fossil fuels and develop indigenous biofuels, the Philippines enacted the Biofuels Act of 2006 which currently mandates a 10% by volume blend of 99.6% anhydrous bio-ethanol for commercially sold Unleaded and Premium gasolines. To urge a regulation review of the anhydrous requirement and examine the suitability for automotive use of hydrous bioethanol (HBE) blends, preliminary engine dynamometer tests at 1400–4400 rpm were conducted to measure specific fuel consumption (SFC) and power. In this study, HBE (95 % ethanol and 5% water by volume) produced from sweet sorghum using a locally-developed process, was blended volumetrically with three base gasoline fuels — Neat, Unleaded, and Premium. The four HBE blends tested were 10% and 20% with Neat gasoline, 20% with Unleaded gasoline, and 20% with Premium gasoline.\u0000 For blends with Neat gasoline, the SFC of the 10%HBE blend was comparable with to slightly higher than Neat gasoline. The SFC of the 20%HBE blend was comparable with Neat gasoline up to 2800 rpm and lower beyond this speed thus being better overall than the 10%HBE blend. Compared to their respective commercial base fuels, the HBE-Unleaded blend showed lower SFC while the HBE-Premium blend yielded slightly higher SFC over most of the engine speed range. Between commercial fuel blends, the HBE-Unleaded blend gave better SFC than the HBE-Premium blend. Power was practically similar for the fuels tested. No engine operational problems and fuel blend phase separation were encountered during the tests. This preliminary study indicated the suitability of and possible optimum hydrous bio-ethanol blends for automotive use under Philippine conditions.","PeriodicalId":219138,"journal":{"name":"ASME 2019 13th International Conference on Energy Sustainability","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123789887","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}
A coupled thermochemical/electrochemical cycle was investigated to produce hydrogen from renewable resources. Like a conventional thermochemical cycle, this approach leverages chemical energy stored in a thermochemical working material that is reduced thermally by solar energy. However, in this concept, the stored chemical energy provides only a fraction of the energy required for effectively splitting steam to produce hydrogen. To push the reaction towards completion, an electrically-assisted proton-conducting membrane is employed to separate and recover hydrogen as it is produced. This novel coupled-cycle concept provides several benefits. First, the required oxidation enthalpy of the reversible thermochemical material is decreased, enabling the process to occur at lower temperatures. Second, removing the requirement for spontaneous steam splitting widens the scope of materials compositions, allowing for less expensive/more abundant elements to be used. Lastly, thermodynamics calculations suggest that this concept can potentially reach higher efficiencies than photovoltaic-to-electrolysis hydrogen production. A novel thermochemical/electrochemical test stand was conceptualized and constructed to prove the concept, and the practical feasibility of the proposed coupled cycle was assessed by validating the individual components of the system: proton conduction across a BaCe0.1Zr0.8Y0.1O3-δ (BCZY18) membrane, thermochemical activity of the CaAl0.2Mn0.8O3−δ (CAM28) working material reduced at 650 °C, and indirect observation of hydrogen production.
{"title":"Renewable Hydrogen Production via Thermochemical/Electrochemical Coupling","authors":"S. Babiniec, A. Ambrosini, James E Miller","doi":"10.1115/ES2019-3905","DOIUrl":"https://doi.org/10.1115/ES2019-3905","url":null,"abstract":"\u0000 A coupled thermochemical/electrochemical cycle was investigated to produce hydrogen from renewable resources. Like a conventional thermochemical cycle, this approach leverages chemical energy stored in a thermochemical working material that is reduced thermally by solar energy. However, in this concept, the stored chemical energy provides only a fraction of the energy required for effectively splitting steam to produce hydrogen. To push the reaction towards completion, an electrically-assisted proton-conducting membrane is employed to separate and recover hydrogen as it is produced. This novel coupled-cycle concept provides several benefits. First, the required oxidation enthalpy of the reversible thermochemical material is decreased, enabling the process to occur at lower temperatures. Second, removing the requirement for spontaneous steam splitting widens the scope of materials compositions, allowing for less expensive/more abundant elements to be used. Lastly, thermodynamics calculations suggest that this concept can potentially reach higher efficiencies than photovoltaic-to-electrolysis hydrogen production. A novel thermochemical/electrochemical test stand was conceptualized and constructed to prove the concept, and the practical feasibility of the proposed coupled cycle was assessed by validating the individual components of the system: proton conduction across a BaCe0.1Zr0.8Y0.1O3-δ (BCZY18) membrane, thermochemical activity of the CaAl0.2Mn0.8O3−δ (CAM28) working material reduced at 650 °C, and indirect observation of hydrogen production.","PeriodicalId":219138,"journal":{"name":"ASME 2019 13th International Conference on Energy Sustainability","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123453799","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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