The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Satha Aphornratana - One of the best experts on this subject based on the ideXlab platform.
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design of steam ejector in a refrigeration application based on thermodynamic performance analysis
Sustainable Energy Technologies and Assessments, 2019Co-Authors: Natthawut Ruangtrakoon, Satha AphornratanaAbstract:Abstract This paper presents a theoretical calculation method for designing the steam Ejectors for refrigeration applications. The working fluid is assumed to be an ideal gas. The flow processes inside the ejector are analyzed by using thermodynamic and ideal gas equations. The advantage of this paper is that the presentation of the theory and calculation procedure are very easy to understand and follow. A design criterion of a steam ejector is also provided. The experimental results at several operating conditions are used to validate the theoretical results. The validation results show that this calculation method can be used as an efficient tool in the design of steam Ejectors.
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comparison of traditional and crmc ejector performance used in a steam ejector refrigeration
Energy Procedia, 2017Co-Authors: Borirak Kitrattana, Satha Aphornratana, Tongchana Thongtip, Natthawut RuangtrakoonAbstract:Abstract In this paper, performance of a steam ejector designed based on the constant rate of momentum change (CRMC) and traditional ejector were tested in an attempt to compare its performance. Three different Ejectors were designed and constructed; traditional ejector with throat diameter of 19 mm, traditional ejector with throat diameter of 13.4 mm, and CRMC ejector with throat diameter of 13.4 mm. They were designed to be easily equipped with the 1kW experimental ejector refrigerator. The boiler saturation pressure was varied from 130°C to 140°. The evaporator saturation temperature were fixed at 7.5°C. The result show that at the same operating condition and the same ejector area ratio (the area ratio of nozzle throat to ejector throat), CRMC ejector provided higher entrainment ratio than the traditional Ejectors while the critical condenser pressure remain the same.
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performance prediction of steam ejector using computational fluid dynamics part 2 flow structure of a steam ejector influenced by operating pressures and geometries
International Journal of Thermal Sciences, 2007Co-Authors: Thanarath Sriveerakul, Satha Aphornratana, K ChunnanondAbstract:The aim of this study is to reveal the complication of the flow and the mixing process of a steam ejector used in a jet refrigeration cycle by using the simulation software package (FLUENT). In Part 1 of this work, the CFD results of the steam ejector's performance were validated with the experimental values. After the validation is satisfied, this paper is able to analyze the flow phenomena inside the steam ejector when its operating conditions and geometries were varied. Using the applications provided by the CFD software, the flow structure of the modeled Ejectors could be created graphically, and the phenomena inside the flow passage were explored. The CFD method was evaluated as an efficient tool to represent the flow inside a steam ejector.
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Ejectors applications in refrigeration technology
Renewable & Sustainable Energy Reviews, 2004Co-Authors: K Chunnanond, Satha AphornratanaAbstract:This paper provides a literature review on Ejectors and their applications in refrigeration. A number of studies are grouped and discussed in several topics, i.e. background and theory of ejector and jet refrigeration cycle, performance characteristics, working fluid and improvement of jet refrigerator. Moreover, other applications of an ejector in other types of refrigeration system are also described.
Scott Elrod - One of the best experts on this subject based on the ideXlab platform.
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ultra high throughput microarray generation and liquid dispensing using multiple disposable piezoelectric Ejectors
Journal of Biomolecular Screening, 2004Co-Authors: Huangpin Ben Hsieh, Dave White, Frank Torres, Bob Krivacic, Bob Kowalski, Robert Matusiak, John S Fitch, Richard H Bruce, Scott ElrodAbstract:The authors have constructed an array of 12 piezoelectric Ejectors for printing biological materials. A single-ejector footprint is 8 mm in diameter, standing 4 mm high with 2 reservoirs totaling 76 µL. These Ejectors have been tested by dispensing various fluids in several environmental conditions. Reliable drop ejection can be expected in both humidity-controlled and ambient environments over extended periods of time and in hot and cold room temperatures. In a prototype system, 12 Ejectors are arranged in a rack, together with an X-Y stage, to allow printing any pattern desired. Printed arrays of features are created with a biological solution containing bovine serum albumin–conjugated oligonucleotides, dye, and salty buffer. This ejector system is designed for the ultra-high-throughput generation of arrays on a variety of surfaces. These single or racked Ejectors could be used as long-term storage vessels for materials such as small molecules, nucleic acids, proteins, or cell libraries, which would allow for efficient preprogrammed selection of individual clones and greatly reduce the chance of cross-contamination and loss due to transfer. A new generation of design ideas includes plastic injection–molded Ejectors that are inexpensive and disposable and handheld personal pipettes for liquid transfer in the nanoliter regime. (Journal of Biomolecular Screening 2004:85-94)
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Ultra-high-throughput microarray generation and liquid dispensing using multiple disposable piezoelectric Ejectors
Journal of Biomolecular Screening, 2004Co-Authors: Huangpin Ben Hsieh, Dave White, Frank Torres, Bob Krivacic, Bob Kowalski, Richard Bruce, Robert Matusiak, Joy Roy, John Fitch, Scott ElrodAbstract:The authors have constructed an array of 12 piezoelectric Ejectors for printing biological materials. A single-ejector footprint is 8 mm in diameter, standing 4 mm high with 2 reservoirs totaling 76 micro L. These Ejectors have been tested by dispensing various fluids in several environmental conditions. Reliable drop ejection can be expected in both humidity-controlled and ambient environments over extended periods of time and in hot and cold room temperatures. In a prototype system, 12 Ejectors are arranged in a rack, together with an X - Y stage, to allow printing any pattern desired. Printed arrays of features are created with a biological solution containing bovine serum albumin conjugated oligonucleotides, dye, and salty buffer. This ejector system is designed for the ultra-high-throughput generation of arrays on a variety of surfaces. These single or racked Ejectors could be used as long-term storage vessels for materials such as small molecules, nucleic acids, proteins, or cell libraries, which would allow for efficient preprogrammed selection of individual clones and greatly reduce the chance of cross-contamination and loss due to transfer. A new generation of design ideas includes plastic injection molded Ejectors that are inexpensive and disposable and handheld personal pipettes for liquid transfer in the nanoliter regime.
Vasko N. Šarevski - One of the best experts on this subject based on the ideXlab platform.
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Ejector Refrigeration/Heat Pump Systems
Water (R718) Turbo Compressor and Ejector Refrigeration Heat Pump Technology, 2020Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:A comprehensive review of the investigations of ejector refrigeration/heat pump cycles is presented in this chapter. Thermal and performance characteristics of simple and combined ejector refrigeration systems, heat pumps, cogenerative, and polygenerative systems are investigated in conditions where low-temperature heat (solar energy, waste heat, geothermal energy) is used. The ejector systems are technically and economically viable and competitive in comparison with conventional refrigeration systems. Viability of implementation of two-phase Ejectors in compressor refrigeration systems for reduction of the throttling losses depends on the refrigerant thermodynamic properties, refrigeration cycle operating conditions as well on the degree to which the two-phase ejector flow field has been optimally designed. The experiences and results of these investigations are valuable for creating the concepts and developmental strategies for novel refrigeration cycles with two-phase Ejectors. A novel water (R718) two-phase ejector refrigeration cycle is proposed and its thermal and performance characteristics are estimated.
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Characteristics of R718 refrigeration/heat pump systems with two-phase Ejectors
International Journal of Refrigeration, 2016Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:The paper describes investigations of R718 refrigeration cycles with two-phase ejector as a compression device. The complex thermal and flow phenomena inside two-phase ejector flow field are analyzed and characteristics of two-phase Ejectors are estimated. Results of investigations of numerous refrigeration systems with two-phase Ejectors are analyzed and recommendations for optimal geometric parameters of two-phase Ejectors are summarized. Novel R718 refrigeration/heat pump systems are proposed: simple two-phase ejector cooling cycle, two-phase ejector heat pump cycle applied in evaporators–concentrators, and combined compact R718 centrifugal compressor–two-phase ejector water chiller for air conditioning application, and their thermal and performance characteristics are estimated.
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Chapter 6 – Ejector Refrigeration/Heat Pump Systems
Water (R718) Turbo Compressor and Ejector Refrigeration Heat Pump Technology, 2016Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:A comprehensive review of the investigations of ejector refrigeration/heat pump cycles is presented in this chapter. Thermal and performance characteristics of simple and combined ejector refrigeration systems, heat pumps, cogenerative, and polygenerative systems are investigated in conditions where low-temperature heat (solar energy, waste heat, geothermal energy) is used. The ejector systems are technically and economically viable and competitive in comparison with conventional refrigeration systems. Viability of implementation of two-phase Ejectors in compressor refrigeration systems for reduction of the throttling losses depends on the refrigerant thermodynamic properties, refrigeration cycle operating conditions as well on the degree to which the two-phase ejector flow field has been optimally designed. The experiences and results of these investigations are valuable for creating the concepts and developmental strategies for novel refrigeration cycles with two-phase Ejectors. A novel water (R718) two-phase ejector refrigeration cycle is proposed and its thermal and performance characteristics are estimated.
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Water (R718) Ejectors
Water (R718) Turbo Compressor and Ejector Refrigeration Heat Pump Technology, 2016Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:Thermal, flow, and performance characteristics of single-phase and two-phase refrigeration Ejectors are analyzed, with emphasis on R718 Ejectors. A calculating procedure for estimation of the main parameters, design, and performance characteristics of the Ejectors is presented. Two main sources of thermodynamic irreversibility are discussed: the process of momentum transfer in the mixing section and shock waves (feature for gas and dry vapor fluid flow), or dispersed shock waves (feature for dominantly vapor two-phase fluid flow), or pseudo-shock waves (feature for dominantly liquid two-phase fluid flow) in the ejector fluid flow. By appropriate choice of refrigerant and optimal design of the ejector flow field elements (recommendations are given in the chapter), the ejector systems can be successfully applied in various refrigeration/heat pump systems, and also in combined (hybrid) and polygeneration thermal systems for utilization of low temperature heat, geothermal energy, solar energy, and waste heat.
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Preliminary study of a novel R718 refrigeration cycle with single stage centrifugal compressor and two-phase ejector
International Journal of Refrigeration-revue Internationale Du Froid, 2014Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:Abstract The paper describes the investigations of a novel R718 refrigeration cycle with single stage centrifugal compressor and two-phase ejector as a second stage compression device. The limitations of the R718 centrifugal stage pressure ratio, connected with small molecular mass of the water and high isentropic exponent, result on high impeller peripheral speed, high Mach number and high discharge temperature. Reynolds number is low and dimensions of the compressor stage are large. The complex thermal and flow phenomena inside two-phase ejector flow field are investigated and performance characteristics are estimated. Although efficiency of the concept of compression with hydraulic pump and two-phase Ejectors is lower, the integration of two-phase Ejectors in the R718 centrifugal unit results in low cost high capacity refrigeration system with high energy efficiency, competitive with traditional refrigeration systems by environmental, technical and economical reasons.
Huangpin Ben Hsieh - One of the best experts on this subject based on the ideXlab platform.
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ultra high throughput microarray generation and liquid dispensing using multiple disposable piezoelectric Ejectors
Journal of Biomolecular Screening, 2004Co-Authors: Huangpin Ben Hsieh, Dave White, Frank Torres, Bob Krivacic, Bob Kowalski, Robert Matusiak, John S Fitch, Richard H Bruce, Scott ElrodAbstract:The authors have constructed an array of 12 piezoelectric Ejectors for printing biological materials. A single-ejector footprint is 8 mm in diameter, standing 4 mm high with 2 reservoirs totaling 76 µL. These Ejectors have been tested by dispensing various fluids in several environmental conditions. Reliable drop ejection can be expected in both humidity-controlled and ambient environments over extended periods of time and in hot and cold room temperatures. In a prototype system, 12 Ejectors are arranged in a rack, together with an X-Y stage, to allow printing any pattern desired. Printed arrays of features are created with a biological solution containing bovine serum albumin–conjugated oligonucleotides, dye, and salty buffer. This ejector system is designed for the ultra-high-throughput generation of arrays on a variety of surfaces. These single or racked Ejectors could be used as long-term storage vessels for materials such as small molecules, nucleic acids, proteins, or cell libraries, which would allow for efficient preprogrammed selection of individual clones and greatly reduce the chance of cross-contamination and loss due to transfer. A new generation of design ideas includes plastic injection–molded Ejectors that are inexpensive and disposable and handheld personal pipettes for liquid transfer in the nanoliter regime. (Journal of Biomolecular Screening 2004:85-94)
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Ultra-high-throughput microarray generation and liquid dispensing using multiple disposable piezoelectric Ejectors
Journal of Biomolecular Screening, 2004Co-Authors: Huangpin Ben Hsieh, Dave White, Frank Torres, Bob Krivacic, Bob Kowalski, Richard Bruce, Robert Matusiak, Joy Roy, John Fitch, Scott ElrodAbstract:The authors have constructed an array of 12 piezoelectric Ejectors for printing biological materials. A single-ejector footprint is 8 mm in diameter, standing 4 mm high with 2 reservoirs totaling 76 micro L. These Ejectors have been tested by dispensing various fluids in several environmental conditions. Reliable drop ejection can be expected in both humidity-controlled and ambient environments over extended periods of time and in hot and cold room temperatures. In a prototype system, 12 Ejectors are arranged in a rack, together with an X - Y stage, to allow printing any pattern desired. Printed arrays of features are created with a biological solution containing bovine serum albumin conjugated oligonucleotides, dye, and salty buffer. This ejector system is designed for the ultra-high-throughput generation of arrays on a variety of surfaces. These single or racked Ejectors could be used as long-term storage vessels for materials such as small molecules, nucleic acids, proteins, or cell libraries, which would allow for efficient preprogrammed selection of individual clones and greatly reduce the chance of cross-contamination and loss due to transfer. A new generation of design ideas includes plastic injection molded Ejectors that are inexpensive and disposable and handheld personal pipettes for liquid transfer in the nanoliter regime.
Milan N. Šarevski - One of the best experts on this subject based on the ideXlab platform.
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Ejector Refrigeration/Heat Pump Systems
Water (R718) Turbo Compressor and Ejector Refrigeration Heat Pump Technology, 2020Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:A comprehensive review of the investigations of ejector refrigeration/heat pump cycles is presented in this chapter. Thermal and performance characteristics of simple and combined ejector refrigeration systems, heat pumps, cogenerative, and polygenerative systems are investigated in conditions where low-temperature heat (solar energy, waste heat, geothermal energy) is used. The ejector systems are technically and economically viable and competitive in comparison with conventional refrigeration systems. Viability of implementation of two-phase Ejectors in compressor refrigeration systems for reduction of the throttling losses depends on the refrigerant thermodynamic properties, refrigeration cycle operating conditions as well on the degree to which the two-phase ejector flow field has been optimally designed. The experiences and results of these investigations are valuable for creating the concepts and developmental strategies for novel refrigeration cycles with two-phase Ejectors. A novel water (R718) two-phase ejector refrigeration cycle is proposed and its thermal and performance characteristics are estimated.
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Characteristics of R718 refrigeration/heat pump systems with two-phase Ejectors
International Journal of Refrigeration, 2016Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:The paper describes investigations of R718 refrigeration cycles with two-phase ejector as a compression device. The complex thermal and flow phenomena inside two-phase ejector flow field are analyzed and characteristics of two-phase Ejectors are estimated. Results of investigations of numerous refrigeration systems with two-phase Ejectors are analyzed and recommendations for optimal geometric parameters of two-phase Ejectors are summarized. Novel R718 refrigeration/heat pump systems are proposed: simple two-phase ejector cooling cycle, two-phase ejector heat pump cycle applied in evaporators–concentrators, and combined compact R718 centrifugal compressor–two-phase ejector water chiller for air conditioning application, and their thermal and performance characteristics are estimated.
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Chapter 6 – Ejector Refrigeration/Heat Pump Systems
Water (R718) Turbo Compressor and Ejector Refrigeration Heat Pump Technology, 2016Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:A comprehensive review of the investigations of ejector refrigeration/heat pump cycles is presented in this chapter. Thermal and performance characteristics of simple and combined ejector refrigeration systems, heat pumps, cogenerative, and polygenerative systems are investigated in conditions where low-temperature heat (solar energy, waste heat, geothermal energy) is used. The ejector systems are technically and economically viable and competitive in comparison with conventional refrigeration systems. Viability of implementation of two-phase Ejectors in compressor refrigeration systems for reduction of the throttling losses depends on the refrigerant thermodynamic properties, refrigeration cycle operating conditions as well on the degree to which the two-phase ejector flow field has been optimally designed. The experiences and results of these investigations are valuable for creating the concepts and developmental strategies for novel refrigeration cycles with two-phase Ejectors. A novel water (R718) two-phase ejector refrigeration cycle is proposed and its thermal and performance characteristics are estimated.
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Water (R718) Ejectors
Water (R718) Turbo Compressor and Ejector Refrigeration Heat Pump Technology, 2016Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:Thermal, flow, and performance characteristics of single-phase and two-phase refrigeration Ejectors are analyzed, with emphasis on R718 Ejectors. A calculating procedure for estimation of the main parameters, design, and performance characteristics of the Ejectors is presented. Two main sources of thermodynamic irreversibility are discussed: the process of momentum transfer in the mixing section and shock waves (feature for gas and dry vapor fluid flow), or dispersed shock waves (feature for dominantly vapor two-phase fluid flow), or pseudo-shock waves (feature for dominantly liquid two-phase fluid flow) in the ejector fluid flow. By appropriate choice of refrigerant and optimal design of the ejector flow field elements (recommendations are given in the chapter), the ejector systems can be successfully applied in various refrigeration/heat pump systems, and also in combined (hybrid) and polygeneration thermal systems for utilization of low temperature heat, geothermal energy, solar energy, and waste heat.
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Preliminary study of a novel R718 refrigeration cycle with single stage centrifugal compressor and two-phase ejector
International Journal of Refrigeration-revue Internationale Du Froid, 2014Co-Authors: Milan N. Šarevski, Vasko N. ŠarevskiAbstract:Abstract The paper describes the investigations of a novel R718 refrigeration cycle with single stage centrifugal compressor and two-phase ejector as a second stage compression device. The limitations of the R718 centrifugal stage pressure ratio, connected with small molecular mass of the water and high isentropic exponent, result on high impeller peripheral speed, high Mach number and high discharge temperature. Reynolds number is low and dimensions of the compressor stage are large. The complex thermal and flow phenomena inside two-phase ejector flow field are investigated and performance characteristics are estimated. Although efficiency of the concept of compression with hydraulic pump and two-phase Ejectors is lower, the integration of two-phase Ejectors in the R718 centrifugal unit results in low cost high capacity refrigeration system with high energy efficiency, competitive with traditional refrigeration systems by environmental, technical and economical reasons.