An efficient numerical model for nonisothermal fluid flow through porous media

Temperature transient analysis has gained increasing attention in recent years due to the widespread application of downhole temperature sensors with high resolution and accuracy. With the fast, high resolution, and accurate temperature sensors in oil and gas wells, there is a need for the models and methods for analysis of transient temperature data in order to identify production and well completion problems and calculation of reservoir properties. Although there are many proposed analytical and numerical models, a majority of models are not applicable in practice due to limitations in basic assumptions and computational time. A procedure is proposed for numerical simulation of transient variations of sandface pressure and temperature. The fluid flow and energy equations are decoupled and solved simultaneously and the dependency of all properties on pressure and temperature is treated by nested iteration loops. The solution was compared with some analytical and numerical methods and was found as a computationally efficient calculation method. The benefit of the proposed method is its versatility, simplicity, speed, and ease of implementation in a programming language which can be used in conjunction with well test analysis models to correct for the effect of temperature and also constrain the uncertainty of reservoir parameters. It can also be embedded in compositional and reactive models to widen their applicability and accuracy.