Application of harmonic pulse testing to water-oil displacement

Harmonic pulse testing is a well testing technique in which the injection or production rate is varied in a periodic way. The pressure response to the imposed rates, both in the pulser well and in the observer wells, can be analyzed in the frequency domain to evaluate the reservoir properties. The advantages of this type of test is that dedicated well testing surface equipment is not required and that the test can be performed during ongoing field operations. The application of the harmonic pulse testing methodology to a synthetic water-oil displacement scenario is presented in this paper. Responses for the pulse test analysis were generated using a standard reservoir simulator. Different combinations of parameters can be estimated depending on the nature of the well for which the pressure data is available: effective permeability and skin in the pulser (injector) well; effective permeability and total compressibility in the observation (producing) wells. Results proved that the value of these parameters at different stages of water flooding is in line with the evolution of the water-oil displacement around the injector and between the injector and the producers. Non-physical values obtained for the total compressibility point at the presence of permeability anisotropy.