Effect of Mixing Chamber Geometry on Steam Ejector Performance

The flow fields, including the distributions of velocity, pressure and Mach number, in a steam ejector, were mathematically modeled and numerically simulated with Fluent software.The influence of the lengths of the conical and cylindrical sections of the mixing chamber, on the entrainment ratio of steam ejector was investigated.The simulated results show that the lengths of the conical and cylindrical sections all have a major impact.For example, at a given cylindrical diameter D, as the conical section length increases, the entrainment ratio changes in an increase-decrease mode, peaking at a length of 2 D; similarly, as the cylindrical section length increases, the entrainment ratio varies in an increase-decrease manner, maximizing at a length of 6 D.We suggest that the simulated results be of some technological interest in design optimization of steam ejector.