Research On Flow Fields And Experimentation Of Supersonic Gas Separator With Diversion Cone

Natural gas is widely used as a kind of clean energy, however the process of dehydration is complicated. Supersonic condensation separation has attracted great interest. The Supersonic separator combines expansion, separation and compression in a whole apparatus. Obviously, the whole process takes the advantage of pressure itself without any external force, therefore this technology possesses great prospects and commercial value.In this dissertation, a novel diversion-cone supersonic gas separator is devised and experimental platform is set up. In addition, the numerical models are established to study the internal flow fields and obtain optimal structural parameters. The influence of area ratio and pressure ratio on flow fields are studied according to theoretical formulas, which provides basis for choosing optimal area ratio. The conclusions are as follows:The established turbulent models and spontaneous condensation gas mixture model can reflect the real internal flow fields and condensation status. Besides, the three-dimensional geometric model of axial-flow cyclone are set up and the conclusion illustrates axial-flow cyclone has the advantage of less pressure loss and higher centrifugal acceleration compared with traditional tangential cyclone. The axial-flow cyclone not only avoids the energy loss when mixture gas strikes on blades efficiently but also makes the centrifugal acceleration order of 107g, which guarantees the droplets can be threw to the surface of the nozzle in a short time.A novel supersonic separator with diversion cone is designed as well as the three-dimensional geometric model in order to find out the optimal structural parameters. The conclusions show that optimal area ratio is 1.27 and makes the highest mach number 1.19 and the lowest static temperature 234K regarding to the pressure ratio 1.5. The condensation status is predicted by spontaneous condensation Eulerian model, which shows that supersaturation keeps higher than 1. A range of condensation nucleus are formed in the throat of the nozzle.Based on one-dimensional isentropic flow of varying cross-section theory, the effects of area ratio and pressure ratio on internal flow fields are studied. The conclusions are as follows: the smaller the area ratio is,the easier the whole nozzle reaches supersonic status, which makes the whole nozzle a low temperature and good for condensation. The optimal area ratio is the largest area ratios among the area ratio that guarantee the whole nozzle supersonic. In that circumstance, the separation efficiency is the highest since the whole nozzle stays supersonic and have the lowest static temperature.the experimental platform is set up and the concusions are:ethanol removal rate and dew point drop first increase with pressure ratio and then decrease. The best pressure ratio is 1.3, when the area ratio of 1.27, the ethanol removal rate was 47.4%, the dew point drop is 7.0 K. In pressure ratio fixed cases, separation efficiency decreases with area ratio. Besides compared with inner-cone SGS, ethanol removal rate of diversion-cone SGS are increased. When the pressure ratio is 1.3 and area ratio is 1.27, the ethanol removal rate is improved 1.9 times.