This paper reports a study on the effect of helical, spiral, and helical-spiral combination manifold configuration on air motion and turbulence inside the cylinder of a Direct Injection (DI) diesel engine motored at 3000 rpm. Three-dimensional model of the manifolds and the cylinder is created and meshed using the pre-processor GAMBIT. The flow characteristics of these engine manifolds are exam...

The conditions in which meridional recirculations appear in swirling flows above a fixed wall are analysed. In the classical Bodewädt problem, where the swirl tends towards an asymptotic value away from the wall, the well-known "tea-cup effect" drives a flow away from the plate at the centre of the vortex. Simple dimensional arguments applied to a single vortex show that if the intensity of the...

Abstract—A 3C-2D PIV technique was applied to investigate the swirling flow generated by an axial plus tangential type swirl generator. This work is focused on the near-exit region of an isothermal swirling jet to characterize the effect of swirl on the flow field and to identify the large coherent structures both in unconfined and confined conditions for geometrical swirl number, Sg = 4.6. Eff...

This paper presents a numerical investigation of two horizontally mounted four-lobed swirl pipes in terms of swirl induction effectiveness into flows passing through them. The swirl flows induced by the two swirl pipes have the potential to improve the efficiency of Clean-In-Place procedures in a closed processing system by local intensification of hydrodynamic impact on the internal pipe surfa...

In this paper the static pressure field of an annular swirling jet is measured indirectly using stereo-PIV measurements. The pressure field is obtained from numerically solving the Poisson equation, taken into account the axisymmetry of the flow. At the boundaries no assumptions are made and the exact boundary conditions are applied. Since all source terms can be measured using stereo-PIV and t...

A general procedure is presented for computing axisymmetric swirling vortices which are steady with respect to an inviscid flow that is either uniform at infinity or includes shear. We consider cases both with and without a spherical obstacle. Choices of numerical parameters are given which yield vortex rings with swirl, attached vortices with swirl analogous to spherical vortices found by Moff...

In this study, the thermal characteristics of turbulent nanofluid flow in a helical tube in the tube heat exchanger (HTTHE) were assessed numerically through computational fluid dynamics (CFD) simulation. The findings of both the turbulent models: realizable k-epsion (k-ε) and re-normalisation group (RNG) k-epsilon were compared. The temperature distribution contours show that realizable and RN...