The application of high-precision downhole temperature sensors has resulted in pressure-transient analysis (PTA) being complemented or replaced by temperature-transient analysis (TTA). However, the derivation and use of TTA solutions is challenging because of the small value of the measured temperature change and the more-complex nature of the governing physics and equations. In particular, analysis work flows for wells producing gas or gas/liquid mixtures are still lacking because most published liquid TTA solutions cannot be applied in the presence of gas. The complete paper addresses a work flow for a dry-gas-producing well.
Introduction
Applications of downhole temperature measurements can be divided into two broad classes based on the type of temperature models used and the reservoir-flow regimes analyzed. The first class uses semisteady-state models, usually in conjunction with measurements made at a single point in time by distributed-temperature sensors (DTSs). The second class of models uses TTA with both point and distributed measurements made over a period of time.
TTA is relatively tolerant to measurement accuracy.
