Evaluation of a Reverse Brayton Cycle Heat Pump for Lunar Base Cooling 941271
This paper explores the possibilities of cooling a permanently inhabited lunar base with a reverse Brayton cycle Thermal Control System (TCS). Based on an initial stage outpost, the cooling needs are defined. A thermodynamic performance model for the Brayton cycle is derived using ideal gas analysis. This model includes inefficiencies and irreversibilities of the components. The free parameters in the thermodynamic model are successively removed using limiting values for efficiencies and determining operating parameters by suboptimizations. In essence a model for cooling efficiency as a function of rejection temperature alone is obtained. For every component of the system a mass model is applied and the overall mass is determined. The last remaining degree of freedom, the rejection temperature, is eliminated by an optimization for lowest overall mass. The result for minimal TCS mass is compared to a reference TCS using a Rankine cycle. It is found that the Brayton cycle is not competitive with the Rankine TCS.
Citation: Sridhar, K., Nanjundan, A., Gottmann, M., Swanson, T. et al., "Evaluation of a Reverse Brayton Cycle Heat Pump for Lunar Base Cooling," SAE Technical Paper 941271, 1994, https://doi.org/10.4271/941271. Download Citation
Author(s):
K. R. Sridhar, Ashok Nanjundan, Matthias Gottmann, Theodore D. Swanson, Jeffrey Didion
Affiliated:
University of Arizona, NASA Goddard Space Flight Center
Pages: 9
Event:
International Conference On Environmental Systems
ISSN:
0148-7191
e-ISSN:
2688-3627
Also in:
SAE 1994 Transactions: Journal of Aerospace-V103-1
Related Topics:
Control systems
Thermodynamics
Pumps
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