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Prediction of cavitation inside mini-sac Diesel injector nozzle using computational fluid dynamics

Bansode Vaibhav, Verma Munna, Pandhare Amar, Shinde Sandip

Journal of Mechanical and Energy Engineering

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2022

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Vol. 6, No 1

7--12

EN

The performance of the internal flow of the fuel injector is impeded by several factors. The nozzle is one of the factors, being typically about a millimeter long and a fraction of a millimeter in diameter. Cavitation inside the diesel injector nozzle is associated with local pressure distribution. At flow areas with sharp corners, the pressure may locally drop below vapour pressure. The aim of this study is to assess the impact of turbulence and cavitation models on the prediction of flow in diesel injection nozzle. In the present study, an analysis of an existing 6 hole mini-sac diesel injector nozzle is carried out using a CFD package. The main objective of the research is to design a nozzle to avoid cavitation and to find out the contribution of different parameters through parametric study. Cavitation is a complex phenomenon whose appearance depends on the physical as well as flow properties of the flowing substance. Thus, for a better visualization of cavitation, a 3D CFD simulation of mini-sac injector nozzle is carried out. An analysis of a single nozzle hole of a mini-sac diesel injector nozzle is considered for the analysis, as the flow is uniformly distributed through each nozzle. As the three-dimensional geometry of mini-sac nozzle is complicated, therefore tet/hybrid element with T-Grid meshing scheme is used, for good surface meshing. The analysis is carried out at injection pressure of 5 00 bar. The CFDresults are validated against test data with the maximum deviation for the mass flow rate of 8.67% at full needle lift.

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Analysis of tribological processes occuring in precision pairs based on example of fuel injection pumps of marine diesel engines

Bejger A., Drzewieniecki J.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2015

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nr 41 (113)

9--16

EN

This article draws attention to the problems of maintaining fuel injection pumps of marine diesel engines in the conditions of use of residual fuels whose quality is steadily deteriorating, and also burned under engine’s reduced load and in situations where the international rules require a temporary change over into distillate fuels. The analysis of tribological processes occurring in hydraulic precision pairs of fuel injection pump such as barrel-plunger was presented and the types of occurring wears were discussed based on author’s own operational experience. There was pointed out the need for additional methods of verification / evaluation of technical condition using of technical diagnostic methods.

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Wpływ pola prędkości za wirnikiem wstępnym na własności ssawne wirnika pompy wielostopniowej

Janczak M., Plutecki J.

Systems : journal of transdisciplinary systems science

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2008

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Vol. 13, spec. iss. 1/2

205--211

EN

The impellers of multistage pumps has lower suction performance. To improve pumps suction performance was designed helical inducer. The flow field behind inducer was changed and it was different from normal inlet flow to impeller. This paper described a numerical investigations the influence of changeable flow field behind inducer on suction performance centrifugal impeller. In the results changeable inlets flow was increased require net positive suction head. It was caused by higher relative velocity of flow and small attack angle, so the cavitations bubble was formed inside blade channel. Cavitations bubble in this area more disturbed flow throw impeller and brought to quickly brake dawn cavitations curves.