Computational and experimental investigation of air supply duct structure in Air-Source water chiller test rooms

Abstract

Air source water chiller (ASWC) (8–90 kW) performance test rooms are expected to be built to manipulate the interior air field only within the prescribed range. The internal air flow field of the test room for ASWC is determined by air supply from the air outlets. In this investigation, the air field of the test room is analyzed in calculation with the air velocities set at 1.5 m/s, 2.0 m/s, 2.5 m/s and 3.0 m/s in six air supply ducts including square duct (model A, control group), the air supply duct at 30˚(B)/45˚(C)/60˚(D) slope, air supply duct with equal height continuous slope (E) and that with equal air flow continuous slope (F). High similarity is found between calculation results and experimental verification thereafter in most of the models. Based on calculation and experiment results, an integrated index is proposed to evaluate the performance of the air supply duct for ASWC test room by taking the air uniformity index, the pressure drop index and the economic index into consideration. Results show that the air supply duct with the 60° slope works best for a satisfying performance in regular application, and that with equal air flow continuous slope is an inferior option.HighlightsAir supply ducts with variable section are designed and compared with traditional square air supply ducts.Various air velocity at each outlet cross section is calculated and compared with experimental verification.Computational calculation methods for different kinds of air supply ducts are proposed to calculate the wind velocity for each outlet.An integrated index is proposed to evaluate the thermal performance of ASWC performance test room.