3D tangentially injected swirling recirculating flow in a nozzle with a slotted‐tube—Effects of groove parameters

Abstract

SUMMARYA numerical prediction for 3D swirling recirculating flow in an air-jet spinning nozzle with a slotted-tube is carried out with the realizable k-ε turbulence model. The effects of the groove parameters on the flow and yarn properties are investigated. The simulation results show that some factors, such as reverse flow upstream of the injector, vortex breakdown downstream of the injector, corner recirculation zone (CRZ) behind the step and vortex ring in the groove caused by the groove geometric variation, are significantly related to fluid flow, and consequently to yarn properties. With increasing groove height, the length of the CRZ increases, while the initial vortex ring in the groove decreases and a same direction rotating vortex forms in the bottom of the groove. Similarly, as the groove width increases, the extent of both vortex breakdown in downstream of the injectors and the vortex ring in the groove increases slightly, whereas the CRZ lengths in stream-wise direction decrease. Some factors, such as the negative tangential velocities, the size of the vortex rings in the grooves and the CRZ, are constant for nozzles with different groove lengths.

Minimum Quantity Lubrication Jet Noise: Passive Control

“…In order to investigate the effects of individual groove parameters on jet noise, a single-factor experimental study was carried out. Guo [17] investigated the effects of groove parameters on gas flow. His research discovered that the longer the groove, the less helpful it is to vortex breakdown, but increasing the width and depth of the groove contributed to vortex breakup.…”

Design, construction and operation of a low-tar biomass (LTB) gasifier for power applications

“…Additionally, this modified design increases the residence time of the gas inside the combustor and the partial oxidation zone resulting in an increased thermal cracking of tars in the partial oxidation zone, minimizing its passage to the reduction zone, decreasing the tar concentration in the producer gas. Swirl flow produced by nozzles may effectively control the residence time distribution of the gas mixture, which is function of the gasifying agent entry angle [15].…”