Abstract
In this study, a novel three-fluid micro-channel evaporator is designed and modeled for a home cooling system with ice energy storage. A two-fluid condenser with similar heat duty is also modeled using micro-channels. Thermal resistance network is used to model the overall heat transfer coefficient of the heat exchangers. The heat transfer model considers the non-symmetric nature of the three-fluid micro-channel evaporator and includes detailed two-phase boiling heat transfer analysis. Similar detailed condensation two-phase heat transfer analysis is conducted for the condenser using the Universal Correlation. The study also conducted extensive code validation for the two-phase boiling and condensation heat transfer correlations before using the code for evaporator and condenser design and analysis. The design conditions for the evaporator and condenser including superheat and subcooling are gathered from ASHRAE standards. The models are expected to accurately predict the heat exchanger sizes for a design requirement, and calculates the fluid outlet temperatures and heat duty for a heat transfer analysis. When combining with the system model of the home cooling system, the evaporator and condenser models can more accurately predict the overall system performance under variable operating conditions. The discretization method results a 62.4 cm length evaporator and a 42.4 cm condenser, which are required to run a 17-kW home-cooling system based on the detailed assumptions and two-phase correlations.
NSTL
Elsevier