Investigation On Oil/Water Two-Phase Profiles Interpretation Based On Temperature And Flowmeter Logs

The quantitative interpretation of temperature well logs is not only one of the great needs for most oil fields, but also given most attention and effort by petroleum engineers and well logging experts both in board and overseas. This study, from the research of the basic mass and heat transference phenomena of the oil/water two-phase flow in the borehole and formation-borehole systems in production oil well as well as their potential mechanisms, extracts a new method of oil/water two-phase profiles interpretation based on temperature and flowmeter logs after carefully mathematical analysis and process. At present, temperature logging is one must in production logging, but most temperature logs are only used to do qualitative analysis to discover the abnormal under wells and some other alike, which is a great waste of the logging information sources for the low level use of the logs. This method, without any new well logging technique, only mines the information quantitatively and does some meaningful work on the quantitative interpretation of the temperature logs, which makes most of the existing resources and have good applicability and practical value.Based on the mass and energy conservation equations of the borehole and formation-borehole system, the decisive functions between production rate and flow flux as well as temperature of the fluids in the borehole as all depth of the well have been deduced in this study. According to the practical situation of production logging in fields, simplification of the functions are introduced so that the basic mathematical model of the oil/water two-phase profile interpretation based on temperature and flowmeter logs as well as its characteristics has been presented.According to the basic mathematical model of the oil/water two-phase profile interpretation based on temperature and flowmeter logs, a similar idea to that of "first getting the retrieve function then the original function" is employed to solve the model. The recursive arithmetic suitable to computer programming has been presented, which make the profile technique available in practical production. Also the theoretical basis of the method have been checked through simple deducing simulation and the influences of various physical parameters on the method have been studied. It is shown that the method is theoretically reliable for the production oil wells without very high production rate and is more suitable in field production for oil wells (i) in area with bigger geothermal gradient; (ii) producing fluids (oil and water) with distinguish thermal characteristics; (iii)producing oil with lower heat capacity or water with higher heat capacity; (iv)with good surface measurement accuracy, as well as the method has certain requirements on the accuracy of the temperature and flowmeter logs sensors.