The quality of drilling and grouting solutions directly affects the speed of construction, service life and efficiency of well repair. Jet mixers are used for sealing and primary dispersion of components of drilling flushing and grouting solutions. They are simple, reliable and technologically advanced. However, more than a century of field experience of their use in drilling, development and overhaul of wells has shown that the jet mixer design is imperfect; weak ejection, unstable supply of materials to the mixing chamber, wetting of materials in the funnel, involvement of a large amount of air in solutions are observed. Further improvement of designs and technology of jet mixers is possible by developing calculation and design methods. We need an adequate equation for calculating jet mixer characteristics as a liquid-gas jet apparatus, that is, the dependence of the dimensionless pressure drop on the ejection coefficient.
The article presents analysis and calculation of jet mixer based on the known theoretical equations of the characteristics of liquid-gas jet devices (with diffusor and diffusorless), taking into account the velocity coefficients of the main elements such as nozzle, inlet section of the mixing chamber, mixing chamber, diffuser. Calculations are performed for ideal and real liquids, the dependences of the relative dimensionless pressure drop on the ejection coefficient are presented. It is shown that the theoretical characteristics reliably reflect only the general tendency of the ejection coefficient to increase with a decrease in the dimensionless pressure drop, but differ significantly from the experimental envelope curves based on the test results of full-scale samples of manufactured jet mixers.
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