Determination of ejection coefficient of liquid-gas ejector based on theory of attached mass

Introduction.The aim of the research was to develop a theory of ejection processes of gas-liquid ejectors with a dispersed liquid jet, based on the application of the principles of the theory of attached mass.Materials and methods.Analytical methods for determining the gas phase flow rate were used.To calculate the main characteristics of water-gas ejectors with a dispersed liquid jet, it was proposed to use the modified Butakov-Hemeon theory.Results and discussion.The basic ejection equation with an energy transfer coefficient not equal to unity is obtained according to the attached mass theory.The change in the supply pressure of the working medium, which constantly occurs in production conditions, leads to a change in the speed regime of the liquid flow.Accordingly, changes in hydraulic resistances and redistribution of energy losses occur.The energy transfer coefficient for this reason is also variable and the calculation of its numerical value is recommended to be carried out for the nominal operating mode of the existing pumping equipment.The design of the receiving chamber affects the amount of losses, since a mixed flow is formed in it.The method for determining energy losses in ejectors consists of finding the numerical values of component losses considering different designs and fluid flow rates.The obtained value of the energy transfer coefficient for an ejector with a cylindrical mixing chamber and a dispersed liquid jet is 1.075, which corresponds to the numerical value of the ejection coefficient of 3.918 (the actual ejection coefficient is 3.47).For an ejector with a combined mixing chamber, the energy transfer coefficient is 1.727, and the ejection coefficient is 6.72 (the actual ejection coefficient is 4.71).Conclusions.The calculation of flow characteristics considers both the flow rate regime in the ejector elements and the design features of the mixing chamber.The accuracy of the determination the ejection coefficient is 12-14%.