Optimization Of Wet Natural Gas Supersonic Nozzle Structure

The water and heavy hydrocarbons contained in natural gas will condense or form hydrates under certain conditions,which will not only reduce the effective conveying capacity of the pipeline,but also cause corrosion or blockage of related equipment,which will have a negative impact on the conveying pipeline.Therefore,dehydration treatment must be carried out before the natural gas is transported.Supersonic hydrocyclone dehydration technology combines expansion and condens-ation with hydrocyclone separation based on the kinetic and thermodynamic princi-ples,thus achieving the separation of water vapor and recombination from natural gas.Based on theory of supersonic dehydration technology,first put forward the design method of equipment parts,taking the actual working condition and the con-ditions of temperament in detail design calculation;Then refer to the actual structure and the results of numerical calculation the corresponding three-dimensional numer-ical calculation model is set up,using ANSYS15.0 carries on the numerical simulat-tion of the study of natural gas in the internal flow field of supersonic vortex dehydration unit flow,droplet condensation and gas-liquid separation.Results show that the supersonic nozzle exit,expanding the lowest temperature can reach 165k.tangential separation speed of 60m/s,can realize fully water vapor condensation and separation;The average diameter of the droplets is 1.2m and most of them can be separated.At the same time,the location of shock wave is located in the diffuser section behind the drainage port,which is conducive to the recovery of temperature and pressure without damaging the droplet condensation environment.On the basis of the research on the internal flow field to drainage mouth of static pressure,separation efficiency and the tangential velocity in order to optimize the index,discusses the change rule under different structure parameters,which determine the optimal structure size;Finally,the performance of the device under different conditions is analyzed.The calculation results show that the influence of different optimization of structural parameters on the above indexes,the constraints are also different,so should according to actual condition to determine the optimal structure;Normal working pressure loss ratio in the range of 40%-70%,the inlet pressure is 0.4MPa,the temperature is 300k,the pressure loss ratio is 70%,the biggest drop dew point can be obtained for 23k;By changing the inlet and outlet pressure and temperature,the dewatering unit can also achieve an ideal dew point drop.It can be seen that the designed supersonic cyclone dewatering unit has a good adaptability to pressure and temperature changes,and can meet the needs of domestic natural gas pipeline transportation applications...