fin-and-tube heat exchangers, experimental infrastructure
Manufactures of fin-and-tube heat exchangers often employ predictive modelling tools in order to reduce development cost and time. These tools require high-fidelity experimental data to validate the accuracy of their predictions. To that end, this paper presents the design and development of a custom-designed pumped refrigerant loop to collect high-fidelity experimental data for fin-and-tube heat exchangers in three operating modes: (1) single-phase refrigerant, (2) evaporator, and (3) condenser mode. It is combined with a small-scale wind tunnel installed in a psychrometric chamber facility for the purpose of validating the recently developed discretized fin-and-tube heat exchanger models (Sarfraz et al., 2019a and 2019b). The pumped refrigerant loop is able to precisely control desired refrigerant test conditions, flowrate to each individual heat exchanger circuit, and has been sized in order to test heat exchanger coils up to a capacity of 5 tons (17.5 kW). A preliminary test plan and uncertainty analysis is presented for the first heat exchanger coil to be tested. The uncertainty analysis showed that the experiment will have the capability of measuring overall coil capacity within ±2%. A design of experiments is also presented, which suggests that 9 tests per coil is an adequate number for minimizing experimental effort. A preliminary experiment was performed which showed that the average air and refrigerant side capacities match to within 1.1% of each other. This provides evidence that the experimental setup has the capability to far exceed the 5% threshold set by ASHRAE Standard 33 (2016).