Design of a Psychrometric Coil Testing Facility for Commercial Size Heat Exchanger Coils

摘要

The design of a closed-loop psychrometric coil testing facility to enable performance testing of commercial-sized heating, ventilation, air-conditioning, and refrigeration (HVAC&R) coils at Oklahoma State University is presented. This paper discusses the design process, preliminary modeling, and predicted operating envelope of the psychrometric coil testing facility. The closed-loop facility will contain the necessary equipment to condition the air supplied to the coil under test such as, electric heaters, and a steam humidification system. The design phase of the facility is complete with details of select subsystems presented here. The design is compliant with multiple ASHRAE standards, including Standard 41.2 (ASHRAE, 1987) which aided in designing the air flow measurement apparatus. A preliminary model of the facility suggests that, heat exchanger coils of up to 20 nominal tons (70.3 kW) of cooling capacity can be tested in a 7 ft (2.13 m) wide by 8 ft (2.44 m) tall test section that can supply a maximum air flow rate of 8,000 CFM (3.78 m~3/s). The facility will be able to operate over an air temperature range of 0°F (-17.8°C) to 140°F (60°C). Future work includes construction of the facility including physical assembly, selection of instrumentation, and development of a graphical controls interface for facility control.