Ejectors usually act as thermal compressors to recover the superfluous water vapor in multi-effect desalination systems. However, the influences of wall conditions on the steam ejector performances were not fully understood. To investigate the effects of the surface roughness and temperature on non-equilibrium condensation and entrainment performance in the steam ejector, a wet steam model was built by a computational fluid dynamics software. Simulation results indicate that the increase of roughness height reduces the ejector performance and attenuates the non-equilibrium condensation phenomenon significantly. Furthermore, as the wall temperature changes in the range of 30–150 °C, the ejector performance varies merely within 4%; however, condensation droplets which may cause erosion damage occurs on the internal surface when the wall has poor adiabatic properties. Therefore, the wall roughness and temperature should be fully considered to enhance the ejector performance and mitigate potential condensation on the wall.

喷射器通常作为热压缩机来回收多效海水淡化系统中多余的水蒸气。然而，壁面条件对蒸汽喷射器性能的影响尚不完全清楚。为了研究表面粗糙度和温度对蒸汽喷射器中非平衡冷凝和夹带性能的影响，通过计算流体动力学软件建立了湿蒸汽模型。仿真结果表明，粗糙度高度的增加降低了喷射器的性能，并显着减弱了非平衡冷凝现象。此外，随着壁温在 30-150°C 范围内变化，喷射器性能的变化仅在 4% 以内；然而，当壁面绝热性能差时，内表面会出现凝结水滴，可能会导致腐蚀损坏。因此，应充分考虑壁面粗糙度和温度，以提高喷射器性能并减少壁面潜在的冷凝。