Studies of coupled vane compressor

Abstract

A new rotary compressor known as the Coupled Vane Compressor (CVC) is developed to address the high rotor to cylinder diameter ratio in existing rotary compressors. The CVC has a potential rotor to cylinder diameter ratio of 0.30 as compared to usually more than 0.75 in all the existing rotary compressors. A smaller rotor will not only help to decrease the size and cost of the compressor but most importantly increases the volumetric capacity of the compressor. In addition, there will also be a reduction in carbon footprint because the raw material saved can be used for other purposes. To determine the feasibility of this design, stress analysis was carried out on the CVC with a rotor to cylinder diameter ratio of 0.62. Besides the mathematical modelling and computer simulation that were done previously, it was also essential to determine the stress value acting on its weakest component, the vane. The vane is a very critical component of the CVC. It helps to separate the different working chamber to prevent leakage and ensure proper operation of a compressor. If the vane were to experience stress beyond its yield stress, it may either deform permanently or break, causing immediate failure of the CVC. With the use of ANSYS computational software, stress simulation was performed for the vane at a regular 30° interval from θ=0° to θ=180°. By applying the boundary condition for each case, the stress value can be determined. Through simulation, it was concluded that the stress experienced by the vane exceeded the allowable stress of 167MPa at certain angular positions of the vane. This suggests that there is a need to improve the design of the vane. By increasing the vane’s width, the stress value experienced by the vane reduces to a certain extent.