Temperature Field Prediction Model for Multi-Layer Commingled Production Wellbore in Intelligent Wells and It's Application

In order to optimize the temperature monitoring equipment and properly determine the positions of measuring points for the multi-layer commingled production of intelligent wells, it is necessary to accurately predict the whole wellbore temperature profile. According to the characteristics of fluid flow in the commingled production wellbore of intelligent wells, a prediction model for single-tubing multi-layer commingled production wellbore temperature with the flow control valve was established. Taking the throttling effect of flow control valve on fluids flow parameters in the system into account, a numerical simulation was carried out in combination with the working conditions of production wells. The model prediction results showed that the wellbore temperature changed regularly with several variables, including the produced fluids properties, liquid production rate, thickness of payzone, production allocation of each layer and geothermal gradient. Compared with the individual production layer, the wellbore temperature of commingled production wells is higher than the average temperature of wells with individually produced layer, and the temperature gradient of commingled production wellbore is the lowest. Based on the principle of minimum temperature measurement error at the flow control valve, an optimization method for temperature sensor index and measuring point was proposed. Taking into consideration the wellbore temperature, temperature gradient and the laws of temperature drop at flow control valve, it was possible to obtain an interpretation method of production layer temperature anomaly. The temperature field prediction model of multi-layer commingled production wellbore in intelligent wells provided a theoretical basis for optimizing the temperature measuring equipment and temperature data interpretation in multi-layer commingled production.