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In case of an accidental leakage of liquefied gas(butane,propane,ammonia,…)due to a vessel breach or a line rupture,a thermodynamic flashing liquid jet can be observed.This phenomenon leads to a violent phase change that will form an explosive or toxic cloud.A better understanding of flashing jets is needed in order both to predict hazardous consequences and to design protection equipment.This liquid pressurized gas(LPG)release involves flash atomization following by a strong mixing with ambient air that promotes heat and mass transfer.As far as atomization is concerned the challenge of such process is the strong coupling between atomization process that interacts with heat and mass transfer.Present study focuses on cooling effect due to liquid vaporization resulting in temperature lower than boiling temperature within the two-phase jet.Indeed,experimental tests have shown that strong cooling effects occurred within a butane or propane two-phase jet.These low temperatures have a strong influence on the jet behavior when it impinges on an obstacle.The objective of this work is to simulate this flashing jet with a particular attention dedicated to the temperature evolution.An Eulerian – Eulerian approach has been implemented within OpenFoam [1] and has been coupled to the numerical model called Thermo-dynamic Equilibrium Model(TEM).This latter model is well suited to simulate the phase change due to both ebullition phenomena and mass transfer between liquid and gas phases [2].The implementation in OpenFoam of these coupled approaches has been carried out by means of the lecture of external thermodynamic data.Comparisons with available experimental results have shown a good agreement regarding temperature profiles along the jet axis in case of butane flashing jet.