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Title: RACK-LEVEL THERMOSYPHON COOLING AND VAPOR-COMPRESSION DRIVEN HEAT RECOVERY: COMPRESSOR MODEL
This paper introduces a novel thermal management solution coupling in-rack cooling and heat recovery system. System-level modeling capabilities are the key to design and analyze thermal performance for different applications. In this study, a semi-empirical model for a hermetically sealed scroll compressor is developed and applied to different scroll geometries. The model parameters are tuned and validated such that the model is applicable to a variety of working fluids. The identified parameters are split into two groups: one group is dependent on the compressor geometry and independent of working fluid, whereas the other group is fluid dependent. By modifying the fluid-dependent parameters using the specific heat ratios of two refrigerants, the model shows promise in predicting the refrigerant mass flow rate, discharge temperature and compressor shaft power of a third refrigerant. Here, the approach has been applied using data for two refrigerants (R22 and R134a) to achieve predictions for a third refrigerant’s (R407c) mass flow rate, discharge temperature, and compressor shaft power, with normalized root mean square errors of 0.01, 0.04 and 0.020, respectively. The normalization is performed based on the minimum and maximum values of the measured variable data. The technique thus presented in this study can be used to accurately predict the primary variables of interest for a scroll compressor running on a given refrigerant for which data may be limited, enabling component-level design or analysis for different operating conditions and system requirements.  more » « less
Award ID(s):
1738782
NSF-PAR ID:
10287014
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Proceedings of the ASME 2021 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems InterPACK2021
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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