Development of an automated throw room and HVAC component acoustic test systems

Michael Anthony Schwob, University of Nevada, Las Vegas


Two facilities for the testing of commercial and residential HVAC air delivery components were developed for the UNLV Ventilation and Acoustic Systems Technology (VAST) Lab. One facility, referred to as the HVAC Acoustic Test Facility (HCATS), will be used to measure the acoustic characteristics of in-duct and duct terminating components. This system will augment the test facility currently used for in-duct passive silencer testing. The other new facility will be used to rate the air performance of HVAC interior inlets and outlets. This system is commonly referred to as a throw room; HCATS includes a supply air fan and closed circuit duct work to carry air to and from a reverberation room. Acoustic measurements are be made in the reverberation room, which has been qualified to ASTM standards. The duct components to be tested are be placed in the ductwork just as they would in normal use. The amount of air delivered to the component is measured using a bank of nozzles which are designed into the air delivery duct path; The throw room is supplied air from an air circulation system designed specifically for the task. This system includes a temperature control system and a bank of nozzles similar to those for the HCATS system. Measurements of the air velocities and temperature in the throw room are made using thermal anemometers and thermocouples carried by a robotic mechanism. A PC computer is used to control the robotic mechanism and record data from the instruments.