The downhole jet pumps experimental studies efficiency improving

Abstract

On the basis of the analysis of the existing criteria of hydraulic similarity, the rules of transferring the results of laboratory tests of jet pumps to the conditions of their operation in the well are considered. The geometric similarity of the flow part of the jet pump is determined by the diameters of the working nozzle, the mixing chamber and the diffuser, the lengths of the mixing chamber and the diffuser, and the distance between the working nozzle and the mixing chamber. The kinematic similarity of mixed flows is determined by the ratio of the speeds or costs of the injected and the workflows, and the dynamic one by the relative pressure in the form of the pressure ratio of the mixed, injected and workflows. To characterize the similarity of motion modes and physical properties of flows in the flowing portion of a jet pump, a Reynolds number for working, injected, and mixed flows can be used. The functional relationship between the quantities that characterize the process of mixing threads can be represented as a relationship between the similarity criteria that are made of them. The equality of any two relevant similarity criteria made up of the basic parameters and initial boundary conditions is a sufficient sign of the similarity of the two systems. A generalized Eulerian criterion is proposed for modeling a wellbore jet pump workflow that provides a relationship between geometric, kinematic, and dynamic dimensionless complexes. Due to the structural features of the ejection systems, the generalized criterion is presented in the form of a ratio of Euler criteria of mixed and working flows, the numerical values of which do not differ from the magnitude of the relative pressure of the jet pump. As a result of the conducted researches, the values ​​of dimensionless complexes are determined, which determine the conditions for transferring the results of experimental studies of the jet pump model to the real design of the well ejection system.