Oil Flow Rate History Reconstruction using Downhole Transient Temperature Data with Wavelet Transform
F. Wang, Y. Zhang, S. Zheng, D. Kong and Z. Huang
Event name: ECMOR XV - 15th European Conference on the Mathematics of Oil Recovery
Session: Poster session
Publication date: 29 August 2016
Info: Extended abstract, PDF ( 1.13Mb )
Price: € 20
Flow rate history is important for pressure-transient analysis and history matching, but due to high cost of metering equipment, the accurate real-time flow rate history for individual well is not always available. This paper presents a method of reconstructing unknown flow rate history from downhole transient temperature data with wavelet transform (WT). Firstly, the time of flow rate change was identified from transient temperature data with the Haar wavelet. As reservoir temperature changes dramatically at the time of flow rate change due to the Joule-Thomson effect, and the time of flow rate change can be identified in the WT detailed signal of the transient temperature data. Then, the proportional relationship between the amplitude of WT coefficients and flow rate change was discovered and theoretically proved. Based on this relationship, the flow rate for each flow event was allocated back from the cumulative production. Finally, with the identified time and calculated flow rate for each flow event, the unknown flow rate history was reconstructed from downhole transient temperature data. This method works well in the oil reservoirs with constant reservoir and fluid properties, and the reliability of this method was demonstrated with a field case study.