Clean-up period flow rate estimation from Multi Discrete Temperature Sensor data

Abstract

Early rate data can be very useful for transient analysis from clean-up periods. Such early analyses may offer reasonable formation properties, allow better design for more rigorous tests later, and offer early estimates of a well's productivity. Flow rates can be measured using many types of flow meters; unfortunately, most of these meters have many issues, particularly for application in clean-up period. Multi Discrete Temperature Sensor (MDTS) data offers a better alternative for rate estimations under different circumstances, especially for production from multiple zones in deep-water assets. However, early-time temperature data are affected by the fact that the drilling circulation causes near-wellbore cooling. The temperature of the reservoir fluid flowing through this cooled zone is lower than that of the formation, and changes with time as the near-wellbore zone gradually warms back. The physical process that reservoir and near-wellbore fluid undergoing needs to be modelled properly to utilize the temperature data read by MDTS. This paper details the development of a model to estimate early-time rates from multiple zones from MDTS data. Application of the model to a field example shows that the model accurately estimates fluid transient temperatures during the clean-up period.