Research into cavitation processes in the trapped volume of the gear pump
Journal Title: Восточно-Европейский журнал передовых технологий - Year 2018, Vol 4, Issue 7
Abstract
<p class="1CxSpFirst">We investigated processes in the trapped volume of the gear pump, formed due to the peculiarities in the geometry of the involute gearing characteristic of the pumps of a given type. In the fluid confined to a trapped volume, at gear rotation, there occur a series of complex hydrodynamic processes. A change in the magnitude of the trapped volume leads to the occurrence of fluid compression, as well as its rarefaction. Reducing the pressure in a fluid below the level of a saturated vapour pressure results in the emergence of cavitation in it. In addition, the result of gear rotation is the vortex motion of fluid that leads to eddies, in the centre of which there is a reduction in pressure; in other words, vortices are the potential embryos of cavitation. High-speed video registration makes it possible to consider in detail the process of emergence and growth of cavitation phenomena in a trapped volume, to explore the dynamics of deformation of a cavitation bubble and a cavity, formed in the trapped volume.</p><p class="1CxSpLast">Based on the results of processing the sequences of frames acquired in the course of this study, we derived dependences that show the character of change in the size of a cavitation bubble and a cavity. The constructed dependences are non-linear and have points of an extremum. The extremum in the time-dependent chart is observed after opening the trapped volume, meaning that it would take some time (approximately 1 ms) for the pressure in a intertooth cavity to grow. In this case, the extremum is observed almost simultaneously both for the deformation of the cavity and the deformation of a single bubble. The radius of a bubble in a liquid depends on individual factors, namely, properties of the fluid and the pressure magnitude, which can be calculated by applying the dependences, given in this work, depending on the conditions for the occurrence of cavitation.</p>
Authors and Affiliations
Dmytro Kostiuk, Denis Kolesnikov, Serhiy Stas, Oleh Yakhno
Keywords
Related Articles
- EP ID EP528097
- DOI 10.15587/1729-4061.2018.139583
- Views 63
- Downloads 0
Development of an approach to ensure stability of the traction direct current system
<p>The result of applying the quantitative approach to the calculation of static stability of the traction power system helped us establish that when a train runs along an actual section there emerge zones with lack of s...
Modeling of melting process in a single screw extruder for polymer processing
<p>We developed a mathematical model of the melting zone of a single-screw extruder for processing of polymers. The model takes into account a heat transfer of a polymer with a worm and a cylinder of an extruder (paramet...
Determining the most dangerous loading application point for asphalt-concrete layers on a rigid base
<p>Operating conditions of asphalt-concrete layers on cement-concrete slabs differ significantly from other structural solutions. Practical road construction applies the insufficiently developed methods for calculating t...
Research into the impact of structural features of combustion chamber in energy-technological units on their operational efficiency
<p>The experimental studies of the influence of the degree of masonry development (geometry) and aerodynamics of the combustion chambers (circuits of combustion products removal) on the energy-technological indicators of...
Universal multifunctional device for heat and mass exchange processes during organic raw material processing
<p>The proposed innovative design solution of universal multifunctional device ensures implementation of the maximum number of heat exchange processes. They are: aging, drying, blanching, boiling, boiling soft, infusion,...