The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform

Ming Fang - One of the best experts on this subject based on the ideXlab platform.

  • study of Material Compatibility for a thermal energy storage system with phase change Material
    Energies, 2018
    Co-Authors: Laura Solomon, Ming Fang
    Abstract:

    The suitability of stainless steel 316L and Inconel 625 for use in a latent heat thermal energy storage (TES) system was investigated. A NaCl–NaF eutectic mixture with a melting temperature of 680 °C was used as the phase change Material (PCM). Containers were filled with the PCM prior to heating to 750 °C, then examined after 100 and 2500 h of high-temperature exposure by analyzing the Material surface and cross-section areas. A small amount of corrosion was present in both samples after 100 h. Neither sample suffered significant damage after 2500 h. The undesirable inter-granular grain boundary attack found in SS316L samples was in the order of 1–2 µm in depth. On Inconel 625 sample surface, an oxide complex formed, resisting Material dissolution into the PCM. The surface morphology of tested samples remained largely unchanged after 2500 h, but the corrosion pattern changed from an initially localized corrosion penetration to a more uniform type. After 2500 h, the corrosion depth of Inconel 625 remained at roughly 1–2 µm, indicating that the corrosion rate decelerated. Both Materials demonstrated good Compatibility with the chosen NaF–NaCl eutectic salt, but the low corrosion activity in Inconel 625 samples shows a performance advantage for long term operation.

William Gilles - One of the best experts on this subject based on the ideXlab platform.

  • Material Compatibility of hvac r system Materials with low global warming potential refrigerants
    Science and Technology for the Built Environment, 2015
    Co-Authors: Julie A Majurin, Steven J Staats, Elyse Sorenson, William Gilles
    Abstract:

    This article summarizes Material Compatibility evaluations of unsaturated hydrofluorocarbon (known as hydrofluoroolefin) refrigerants, and hydrofluoroolefin refrigerants blended with R-32, that were performed to characterize equipment reliability risks associated with the use of next-generation low global warming potential fluorinated refrigerant candidates. Material Compatibility exposures were conducted with R-1234yf, R-1234ze(E), and a three-refrigerant composite blend of R-1234yf, R-1234ze(E), and R-32, with nine different elastomers, three gaskets, five polymers, and ten motor Materials. Exposures were carried out in 100% refrigerant, 50% refrigerant:50% lubricant, and 100% lubricant to encompass the range of refrigerant and lubricant compositions that Materials may encounter in different areas of operating systems. Two different lubricants, a polyol ester and a polyvinyl ether, were evaluated in this study, resulting in a total of 12 different exposure conditions for each of the 27 Materials. A summ...

  • Material Compatibility of HVAC&R system Materials with low global warming potential refrigerants
    Science and Technology for the Built Environment, 2015
    Co-Authors: Julie A Majurin, Steven J Staats, Elyse Sorenson, William Gilles
    Abstract:

    This article summarizes Material Compatibility evaluations of unsaturated hydrofluorocarbon (known as hydrofluoroolefin) refrigerants, and hydrofluoroolefin refrigerants blended with R-32, that were performed to characterize equipment reliability risks associated with the use of next-generation low global warming potential fluorinated refrigerant candidates. Material Compatibility exposures were conducted with R-1234yf, R-1234ze(E), and a three-refrigerant composite blend of R-1234yf, R-1234ze(E), and R-32, with nine different elastomers, three gaskets, five polymers, and ten motor Materials. Exposures were carried out in 100% refrigerant, 50% refrigerant:50% lubricant, and 100% lubricant to encompass the range of refrigerant and lubricant compositions that Materials may encounter in different areas of operating systems. Two different lubricants, a polyol ester and a polyvinyl ether, were evaluated in this study, resulting in a total of 12 different exposure conditions for each of the 27 Materials. A summ...

  • Material Compatibility of HVAC&R system Materials with low GWP refrigerants.
    2014
    Co-Authors: Julie A Majurin, Steven J Staats, William Gilles
    Abstract:

    When assessing the suitability of next generation refrigerants for use with current HVAC&R system Materials, two areas of concern need to be thoroughly investigated and understood: 1) Compatibility of the system Materials when in contact with the fluids, and 2) chemical stability of the fluids when exposed to system Materials. This paper summarizes Material Compatibility evaluations of unsaturated hydrofluorocarbon (HFO) refrigerants, and HFO refrigerants blended with R32, that were conducted to better understand equipment reliability risks associated with the use of next generation low global warming potential (GWP) refrigerant candidates. Material Compatibility exposures were conducted in Parr pressure vessels with R1234yf, R1234ze(E), and a threerefrigerant composite blend of R1234yf, R1234ze(E), and R32 (33% by weight of each), with nine types of elastomers, three gaskets, five polymers, and ten different motor Materials. Exposures were conducted in 100% refrigerant, 50% refrigerant:50% lubricant, and 100% lubricant to encompass the range of refrigerant and lubricant compositions that may be present in different areas of operating systems. Two different lubricants, a polyol ester (POE) and a polyvinyl ether (PVE), were evaluated in the study. In total, each of the Materials was exposed to twelve different conditions. Results of laboratory measurements of the physical property changes of exposed elastomeric and polymeric Materials, and hermetic compressor motor Materials, are presented in this paper. In addition, potential system reliability implications of these results, based on a risk-based ranking approach, are reported.

Laura Solomon - One of the best experts on this subject based on the ideXlab platform.

  • study of Material Compatibility for a thermal energy storage system with phase change Material
    Energies, 2018
    Co-Authors: Laura Solomon, Ming Fang
    Abstract:

    The suitability of stainless steel 316L and Inconel 625 for use in a latent heat thermal energy storage (TES) system was investigated. A NaCl–NaF eutectic mixture with a melting temperature of 680 °C was used as the phase change Material (PCM). Containers were filled with the PCM prior to heating to 750 °C, then examined after 100 and 2500 h of high-temperature exposure by analyzing the Material surface and cross-section areas. A small amount of corrosion was present in both samples after 100 h. Neither sample suffered significant damage after 2500 h. The undesirable inter-granular grain boundary attack found in SS316L samples was in the order of 1–2 µm in depth. On Inconel 625 sample surface, an oxide complex formed, resisting Material dissolution into the PCM. The surface morphology of tested samples remained largely unchanged after 2500 h, but the corrosion pattern changed from an initially localized corrosion penetration to a more uniform type. After 2500 h, the corrosion depth of Inconel 625 remained at roughly 1–2 µm, indicating that the corrosion rate decelerated. Both Materials demonstrated good Compatibility with the chosen NaF–NaCl eutectic salt, but the low corrosion activity in Inconel 625 samples shows a performance advantage for long term operation.

Julie A Majurin - One of the best experts on this subject based on the ideXlab platform.

  • Material Compatibility of hvac r system Materials with low global warming potential refrigerants
    Science and Technology for the Built Environment, 2015
    Co-Authors: Julie A Majurin, Steven J Staats, Elyse Sorenson, William Gilles
    Abstract:

    This article summarizes Material Compatibility evaluations of unsaturated hydrofluorocarbon (known as hydrofluoroolefin) refrigerants, and hydrofluoroolefin refrigerants blended with R-32, that were performed to characterize equipment reliability risks associated with the use of next-generation low global warming potential fluorinated refrigerant candidates. Material Compatibility exposures were conducted with R-1234yf, R-1234ze(E), and a three-refrigerant composite blend of R-1234yf, R-1234ze(E), and R-32, with nine different elastomers, three gaskets, five polymers, and ten motor Materials. Exposures were carried out in 100% refrigerant, 50% refrigerant:50% lubricant, and 100% lubricant to encompass the range of refrigerant and lubricant compositions that Materials may encounter in different areas of operating systems. Two different lubricants, a polyol ester and a polyvinyl ether, were evaluated in this study, resulting in a total of 12 different exposure conditions for each of the 27 Materials. A summ...

  • Material Compatibility of HVAC&R system Materials with low global warming potential refrigerants
    Science and Technology for the Built Environment, 2015
    Co-Authors: Julie A Majurin, Steven J Staats, Elyse Sorenson, William Gilles
    Abstract:

    This article summarizes Material Compatibility evaluations of unsaturated hydrofluorocarbon (known as hydrofluoroolefin) refrigerants, and hydrofluoroolefin refrigerants blended with R-32, that were performed to characterize equipment reliability risks associated with the use of next-generation low global warming potential fluorinated refrigerant candidates. Material Compatibility exposures were conducted with R-1234yf, R-1234ze(E), and a three-refrigerant composite blend of R-1234yf, R-1234ze(E), and R-32, with nine different elastomers, three gaskets, five polymers, and ten motor Materials. Exposures were carried out in 100% refrigerant, 50% refrigerant:50% lubricant, and 100% lubricant to encompass the range of refrigerant and lubricant compositions that Materials may encounter in different areas of operating systems. Two different lubricants, a polyol ester and a polyvinyl ether, were evaluated in this study, resulting in a total of 12 different exposure conditions for each of the 27 Materials. A summ...

  • Material Compatibility of HVAC&R system Materials with low GWP refrigerants.
    2014
    Co-Authors: Julie A Majurin, Steven J Staats, William Gilles
    Abstract:

    When assessing the suitability of next generation refrigerants for use with current HVAC&R system Materials, two areas of concern need to be thoroughly investigated and understood: 1) Compatibility of the system Materials when in contact with the fluids, and 2) chemical stability of the fluids when exposed to system Materials. This paper summarizes Material Compatibility evaluations of unsaturated hydrofluorocarbon (HFO) refrigerants, and HFO refrigerants blended with R32, that were conducted to better understand equipment reliability risks associated with the use of next generation low global warming potential (GWP) refrigerant candidates. Material Compatibility exposures were conducted in Parr pressure vessels with R1234yf, R1234ze(E), and a threerefrigerant composite blend of R1234yf, R1234ze(E), and R32 (33% by weight of each), with nine types of elastomers, three gaskets, five polymers, and ten different motor Materials. Exposures were conducted in 100% refrigerant, 50% refrigerant:50% lubricant, and 100% lubricant to encompass the range of refrigerant and lubricant compositions that may be present in different areas of operating systems. Two different lubricants, a polyol ester (POE) and a polyvinyl ether (PVE), were evaluated in the study. In total, each of the Materials was exposed to twelve different conditions. Results of laboratory measurements of the physical property changes of exposed elastomeric and polymeric Materials, and hermetic compressor motor Materials, are presented in this paper. In addition, potential system reliability implications of these results, based on a risk-based ranking approach, are reported.

H Spliethoff - One of the best experts on this subject based on the ideXlab platform.

  • theoretical analysis and experimental investigation of Material Compatibility between refrigerants and polymers
    Energy, 2018
    Co-Authors: S Eyerer, Peter Eyerer, Markus Eicheldinger, C Wieland, Beatrice Tubke, H Spliethoff
    Abstract:

    A new generation of refrigerants, the hydrofluoroolefines, has been introduced within the last years. These fluids have a significantly smaller Global Warming Potential compared to the state-of-the-art fluids, which are within the class of hydrofluorocarbons. The hydrofluoroolefines are unsaturated molecules consisting of double-bonded carbon atoms. Especially, compared to hydrofluorocarbons, which are saturated molecules, the interaction with polymers might differ. Therefore, this study investigates the Compatibility between polymers and refrigerants, which are commonly used as working fluids in Organic Rankine Cycles or refrigeration units. The Compatibility is evaluated due to a theoretical analysis of the relevant mechanisms of the fluid-polymer interaction and an experimental study. The investigated refrigerants are two state-of-the-art fluids, namely R245fa and R134a, as well as three next-generation refrigerants R1233zd-E, R1234yf and R1234ze-E. In addition, two blends, namely R450a and R513a, as well as a lubricant polyolester are investigated. The polymers comprise six elastomers and two thermoplastics, more specifically, two different compositions of ethylene-propylene-diene rubber, two compositions of fluororubber, chlorobutadiene rubber, nitrile-butadiene rubber, polytetrafluoroethylene and polypropylene. The Material Compatibility is evaluated by changes in volume, weight, Shore hardness as well as in small load hardness. Summing up, 64 different fluid-polymer combinations are tested at two different temperature levels.

  • Material Compatibility of orc working fluids with polymers
    Energy Procedia, 2017
    Co-Authors: S Eyerer, Peter Eyerer, Markus Eicheldinger, C Wieland, H Spliethoff
    Abstract:

    In this study, the Material Compatibility of refrigerants focusing on hydrofluoroolefines (HFO) with typical polymers in ORC plants and refrigeration units is analyzed with consistent testing conditions and a complete uncertainty analysis of the results. One state of-the-art refrigerant, namely R245fa, as well as the low-GWP fluids R1233zd-E and R1234yf are taken into account. The investigated polymers are ethylene-propylene-diene rubber (EPDM), fluoric rubber (FKM) and polytetrafluoroethylene (PTFE). In the case of EPDM, two different compositions are analyzed. To complement the study the Material Compatibility with a polyolester (POE) lubricant is also investigated. The Material Compatibility is evaluated by changes in volume, weight, Shore A as well as in small load hardness. With the small load hardness measurements, the hardness directly at the samples surface can be determined and thus important information on chemical interaction is provided. This study points out the importance of Material Compatibility testing especially investigating the difference between hydrofluorocarbons (HFC) and HFO, because the unsaturated characteristic of the HFO may lead to considerable changes in Material Compatibility compared to HFC refrigerants.