Numerical Simulation of Fountain Formation due to Normal and Inclined Twin-Jet Impingement on Ground

Xiang Zhang,Ramesh K Agarwal

doi:10.3390/fluids5030132

Abstract

The goal of this paper is to study numerically the flow physics of a fountain formed by twin-jet impingement on ground. The incompressible Reynolds-Averaged Navier-Stokes (RANS) equations with realizable k-ε and WA (Wray-Agarwal) turbulence model are employed in the numerical simulations with ANSYS Fluent. A series of numerical simulations for straight and inclined fountain formations are conducted by changing the geometric and flow parameters of twin jets and distance between them. The changes in parameters include variations in the jet Reynolds number from 2 × 104 to 8 × 104, impingement height, distance between the centerlines of the two jets from 1.4D to 16D where D is the jet diameter, and ratio of the Reynolds number of the two jets from 1 to 4. It is shown that different Reynolds numbers of the two jets can result in a fountain that inclines towards the jet with smaller Reynolds number. Detailed flow field simulations for a large number of cases are presented, and the flow physics of fountain formation is analyzed for the first time in the literature.

Highlights

Impinging jets have been widely studied because of their significance in many fluid mechanics and engineering applications
In another important fighter aircraft application related to the propulsion system of a Short-Takeoff and Vertical Landing (STOVL) or Vertical Take-off and Landing (VTOL) aircraft, multiple jets from the jet engine can impinge in the close vicinity of the ground during landing and take-off
Based on results the results presented thispaper, paper,the the following following conclusions can be be drawn: Based on the presented ininthis conclusions can drawn: Numerical results from both k-ε and Wray-Agarwal turbulence model show good agreement

Summary

Introduction

Impinging jets have been widely studied because of their significance in many fluid mechanics and engineering applications. Impinging jets are applied for industrial cleaning, metal cutting and cooling systems of high pressure turbine blades that face extremely high temperatures in gas turbine engine [1,2,3]. In another important fighter aircraft application related to the propulsion system of a Short-Takeoff and Vertical Landing (STOVL) or Vertical Take-off and Landing (VTOL) aircraft, multiple jets from the jet engine can impinge in the close vicinity of the ground during landing and take-off. Barata et al [6]

Objectives

Methods

Results

Conclusion