ANALYSIS OF TEMPERATURE FIELD IN LAYERED RESERVOIR

Abstract

The relevance of the research. At present time the interest in quantitative interpretation of temperature surveys is growing. Individual flow rate and reservoir pressure of each layer, behind-casing flow rate, hydrodynamic layer parameters, characterization of permeability changing at near-wellbore zone become the purposes of quantitative interpretation. Non-stationary temperature and pressure in the well are used as input data for transient processes analysis, and temperature logs are used for quasi-stationary analysis. Determination of individual layer flow rates and near-wellbore zone parameters are of particular interest. The main aim of the research is to assess the degree of affect of reservoir uniformity assumption on the observed temperature for some scenarios of well operation. The methods. A numerical model is developed and investigated, discretization is carried out by the method of control volumes, the method of variable directions is used. The correctness of the numerical solution is verified by comparison with the known analytical solutions. The results. The authors have studied the problem of a nonstationary temperature field in a layered reservoir. The average deviation of the solution for the case of injection can reach 20 % or more, the value depends on the thickness (total) of the reservoir. The average deviation of the solution for the case of injection reaches a maximum of 6–10 hours and then slowly decreases over time. In the case of production, the deviation value can reach 100 %, the maximum is reached at the beginning of recovery. Further, the deviation decreases, reaching after 24 hours the value of the order of 40 % of the initial deviation. Setting the permissible error of the solution in 10 % at modeling recovery in layered reservoirs it is necessary to take into account the stratification at its values above 15–25 %, depending on the scenario of work the well.

Keywords

• geophysics
• thermal logging
• well
• reservoir
• permeability
• numerical solution