The change of the formation temperature is caused by the thermal production of the steam, so that the fluid property in the formation is changed. So the temperature change in the formation and the wellbore needs to be calculated, and the analysis of the thermal production well testing is carried out, including the interpretation of the production profile and the absorption profile, shut-in pressure drop well testing interpretation and the prediction of the productivity.

Wellbore and formation temperature equation and its solution.

Calculation of bottom hole pressure after temperature change caused by thermal production: When steam is injected, temperature affects pressure. Since the temperature influences the viscosity of the liquid in formation seepage, but temperature has no effect on flow velocity (or has little effect), therefore, the seepage equation of formation remains unchanged, but wellbore pressure needs to be modified.

Shut-in pressure drop well testing interpretation

Consider the effect of temperature on shut-in pressure: Because the steam parameters vary greatly with temperature during shut in, the viscosity, compression coefficient and volume coefficient of steam and so on vary with temperature should be considered.

The multi-region composite model is used to represent the approximate range of temperature spread.

Straight well, fracture well and so on can be analyzed.Dual medium reservoir can be considered.Various boundary effects can be considered.