Effect of Spindle Deviation on the Performance of Adjustable Ejectors

Due to the change of working load caused by peak shaving and frequency modulation in power plants, the traditional fixed ejector cannot meet the requirements of high-performance operation under variable load conditions. However, the adjustable ejector with spindle has problems such as the length of the spindle is too long, and the anti-vibration measures are not in place. The spindle vibrates and deflects during the operation of the ejector. In this research, the influence of the structure deviation of the spindle on the ejector performance is evaluated by numerical simulation. The results show that the spindle of the adjustable ejector can obtain the maximum secondary fluid mass flow by controlling the primary fluid. Under different operating conditions, the entrainment ratio of the adjustable ejector is improved by 114.7% compared with that of the fixed ejector. The structural deviation will reduce the entrainment ratio and anti-back pressure capability, and the ejector will change from the critical mode to the sub-critical mode. The deviation between the spindle and the primary nozzle will change the flow field inside the primary nozzle, thus affecting the primary fluid ejection direction and the entrainment ratio.