In the natural gas industry, the nozzle should be set up at the mouth of the well in order to control the production of natural gas. But this can lead to a lower temperature, which can lead to hydrate formation, it affect gas recovery efficiency. In order to make a reasonable use of the ground temperature, the throttle is often placed in the underground, it allow the throttle gas to be properly heated to prevent the formation of hydrates. Wellbore flow mechanism is the theoretical basis of downhole throttli...