An adjustable ejector with a spindle in the nozzle was developed for a wider adjustment range.An experimental study was carried out on the performance of the adjustable ejector.To change the spindle position axially t...An adjustable ejector with a spindle in the nozzle was developed for a wider adjustment range.An experimental study was carried out on the performance of the adjustable ejector.To change the spindle position axially the nozzle throat sectional area could be changed.The ejector flow parameters,such as flow rate,pressure and entrainment ratio,at different spindle positions were measured.The results showed that the adjustable ejector could be used in a wider range of fluid flow rate.When the throat area was reduced,the ultimate discharge pressure would be lower but the entrainment ratio would increase greatly.展开更多
The present study addresses a variable ejector which can improve the ejector efficiency and control the re-circulation ratio under a fixed operating pressure ratio. The variable ejector is a facility to obtain specifi...The present study addresses a variable ejector which can improve the ejector efficiency and control the re-circulation ratio under a fixed operating pressure ratio. The variable ejector is a facility to obtain specific recirculation ratio under a given operating pressure ratio by varying the ejector throat area ratio. The numerical simulations are carried out to provide an understanding of the flow characteristics inside the variable ejector. The sonic and supersonic nozzles are adopted as primary driving nozzles in the ejector system, and a movable cone cylinder, inserted into a conventional ejector-diffuser system, is used to change the ejector throat area ratio. The numerical simulations are based on a fully implicit finite volume scheme of the compressible, Reynolds-Averaged Navier-Stokes equations. The results show that the variable ejector can control the recirculation ratio at a fixed operating pressure ratio.展开更多
文摘An adjustable ejector with a spindle in the nozzle was developed for a wider adjustment range.An experimental study was carried out on the performance of the adjustable ejector.To change the spindle position axially the nozzle throat sectional area could be changed.The ejector flow parameters,such as flow rate,pressure and entrainment ratio,at different spindle positions were measured.The results showed that the adjustable ejector could be used in a wider range of fluid flow rate.When the throat area was reduced,the ultimate discharge pressure would be lower but the entrainment ratio would increase greatly.
文摘喉嘴距是影响喷射器性能的重要结构参数,研究其对喷射器性能的影响对提升喷射器性能有重要意义.本文对喷射器性能进行实验研究,获得不同喉嘴距和运行工况参数下,喷射器性能的变化规律.研究发现:在本实验范围内,喉嘴距对喷射器的临界背压值影响较小,对喷射器引射比影响较大,引射比随喉嘴距的增大先增大后减小.喷射器单相运行时和两相运行时均存在一个最优喉嘴距,最优喉嘴距随低压流体含液量的增大而增大.当喷射器单相运行时,最优喉嘴距为2.8 mm,当低压流体含水量达到0.07 kg/min时,最优喉嘴距为3.6 mm.
文摘The present study addresses a variable ejector which can improve the ejector efficiency and control the re-circulation ratio under a fixed operating pressure ratio. The variable ejector is a facility to obtain specific recirculation ratio under a given operating pressure ratio by varying the ejector throat area ratio. The numerical simulations are carried out to provide an understanding of the flow characteristics inside the variable ejector. The sonic and supersonic nozzles are adopted as primary driving nozzles in the ejector system, and a movable cone cylinder, inserted into a conventional ejector-diffuser system, is used to change the ejector throat area ratio. The numerical simulations are based on a fully implicit finite volume scheme of the compressible, Reynolds-Averaged Navier-Stokes equations. The results show that the variable ejector can control the recirculation ratio at a fixed operating pressure ratio.
