Measurement techniques for multiphase flow in productivity evaluation in petroleum industry

DST is now partly replaced by pumpout wireline formation tester in fluid sampling and reservoir productivity evaluation. With the successful development of the ERCT wireline tester in China, it is important to make advantage of the ERCT´s large volume pumping capability, continuous testing property, complete sampling function and various fluid identity methods to evaluate reservoir more precisely with the tool´s testing data and sampling information. The variation of gas and liquid compressibility factors are studied. And the measurement software is programmed, which can fit the testing pressure of pump chamber stochastically and dynamically, calculate the bubble point pressure of formation fluid automatically according to the slope of the fitted curve. And then whether there is multiphase flow in the reservoir will be judged. Finally the productivity of the reservoir will be evaluated. The research of this paper has great theoretical and application reference. And applications of this research in a well of wireline formation test by COSL have obtained favorable effectiveness.