Author(s): Xinping Long; Jinmu Zhu; Peijie He; Aiguo Liang
Linked Author(s): Xinping Long
Keywords: Jet pump; Confined coaxial jet; Numerical simulation; PIV
Abstract: Using body-fitted coordinate system, Hybrid Finite Analytic Method (HFAM) together with k -ε turbulence model, the flow field in jet pumps was simulated. The simulation took all parts of jet pump into consideration. So, the flow within a jet pump is considered as confined coaxial jet developing in an irregular zone with convergent and divergent part. Also the flow field in throat pipe of jet pumps was measured by PIV. The centerline velocity decay, wall pressure distribution, velocity vector as well as iso-u velocity distribution of jet pumps were obtained. Both simulation and measurement shows apparently that the centerline velocity gets some acceleration just a little downstream of the nozzle, and then decays as usual. The wall pressure declines a little in the entrance and fore of throat pipe. Then, it ascends quickly until the flow reaches the end of throat pipe. In some case, which the two flows mix thoroughly before the end of the throat pipe, the wall pressure will declines slightly because of the friction lose. The velocity vector and iso-u velocity distribution reveals that the jet boundary layer spreads approximately linearly with the flow developing downstream until it reaches the wall of throat pipe. And the structure of fully developed confined coaxial jet flow can be divided into four sections.
Year: 2005