Low Pressure Jet Performance in Systematic Air-conditioning Room with Cross-flow Fan

摘要

In this paper, the air conditioner indoor unit and indoor space are considered together, thus the 2D synthesized jet field model is obtained. Based unstable flow, the numerical simulation of isothermal flows are carried with the overall air-conditioned room combined the heat exchanger by adopting the large eddy simulation method. Several velocities of the impeller are considered to obtain the appropriate isothermal flow flied. Then the aerodynamic noise spectrums near and far field are analyzed with the main surfaces by aero acoustic analogy method. So, the different airflow distributions are obtained at several velocities, a suitable air speed range is given further. Next, a number of aerodynamic characteristics are obtained, such as the vortex distribution. There are four low-frequency characteristic values near the impeller, one broad characteristic frequency at middle-field in the room in static pressure aspect. Another, the numerical simulations in the condition of the 1000 rpm are on target with the experiment which is only considered the cross-flow fan , and this results provide more references for the follow-up experiments. Last, there exists a similar characteristic frequency which is 32Hz. The pressure spectrum density distributions about the shell and tongue vortex are bigger than others. At volute tongue zone, there are other obviously characteristic frequencies which are 260 and 1000Hz, but in the room, there are one peak in pressure spectrum distribution and a broad range in sound pressure level distribution.