Numerical simulation of the flow field structure of liquid nitrogen jet

Abstract

Liquid nitrogen jet is regarded as an excellent technology for the well drilling and reservoir fracturing. To evaluate the flow field structure of liquid nitrogen jet, a 2-D CFD model is established. The transient velocity and temperature fields of liquid nitrogen jet is simulated. The results show that the liquid nitrogen jet also clearly presented the velocity boundary and potential core region similar to the water jet. Given the temperature difference between the jet and surrounding fluid, the liquid nitrogen jet has an obvious temperature boundary, on which the jet temperature is equal to the initial value. According to the phase of the jet, the flow structure can be divided into the liquid nitrogen jet and non-liquid nitrogen jet regions. The temperature boundary shows a larger width than the velocity boundary for liquid nitrogen jet. Moreover, both width and length of the liquid nitrogen jet region are greater than the potential core region.