A Simple Model for Predicting Heat Loss and Temperature Profiles in Thermal Injection Lines and Wellbores With Insulations

Abstract

Abstract Accurate predictions of heat loss and temperature profile in thermal injection lines and wellbores are essential to designing and evaluating thermal operations. Although some sophisticated computer packages are available for such purpose, their accuracies suffer from numerical treatments and model-building skills of inexperienced users. A simple-and-accurate analytical heat transfer model is highly desirable. This paper presents three analytical heat transfer solutions for predicting heat loss and temperature profiles in thermal-insulated flow conduits. The three solutions consist of one steady state flow solution and two transient flow solutions. The two transient flow solutions are for start-up mode and flow rate change mode (shutting-down is a special mode where the flow rate changes to zero). Capability of the analytical model is investigated using a data set that is representative to a typical case of liquid flow in a small-diameter thermal pipeline. An application example is illustrated where the model-calculated temperature profile is used to identify the possible interval of asphaltene deposition in an oil well. The mathematical heat transfer model can also be used for predicting temperature distribution in offshore pipelines.