Mathematical description of the cavitation process in the jet apparatus

The problem of mathematical description of non-steady processes in hydrodynamic systems is currently relevant and requires early resolution. The description of cavitation as a non-steady process is one of the most important issues of hydrodynamics. In this paper, as a result of the analysis and generalization of a priori information, plus transformation of the basic equations describing cavitation processes, a number of expressions are obtained that reflect the behavior of the incompressible fluid main flow in a jet apparatus, taking into account the conduct of hydrodynamic cavitation in it. To create a cavitation process mathematical description, it is proposed to apply an empirical formula for determining the ejected flow pressure. The newly developed mathematical dependencies can be used in the design of jet devices (ejectors, cavitators, ejectors-cavitators) for various purposes in both marine and stationary coastal technological systems for processing fluid media. In particular, it is advisable to use them in the preparation and conditioning of drinking and industrial water, wastewater and oily water purification, etc.

Improvement in cavitation resistance of poly (vinyl butyral) composite films with silica nanoparticles: A technical note

In this study poly (vinyl butyral)/silica (PVB/SiO2) composite films were subjected to the cavitation process. The experiments were carried out with a 10 wt.% PVB solution in ethanol. Silica nanoparticles were added into the solution in different concentration of 1, 3 and 5 wt.% SiO2 in regard to PVB. Composite films were cast from these solutions and subjected to ultrasonic cavitation. Optical images of their surfaces were analyzed before and after cavitation, by Image-Pro Plus software. The results revealed that the PVB film with 5 wt.% SiO2 nanoparticles demonstrated the greatest improvement in microhardness with the best cavitation resistance compared to other films.

Study employment perspectives of cavitation technolo- gies in pipeline transportation

The paper explores the aspects negatively affecting the pipeline transportation of heavy oil and reviews the implementation possibility of cavitation processes as an alternative method of solving occurring problems. Based on the laboratory researches of abnormal oil from Azerbaijan fields, the parameters and technical upgrade of heavy oil in the system of hydrodynamic cavitation have been studied. Moreover, as a result of carried out experiments, the operation mechanism of cavitation process during reduction of heavy oil viscosity has been described and the implementation prospect of this technology in commercial scales analyzed as well.