In the present work, heat transfer characteristics of a turbulent confined slot jet impinging on heated moving plate are studied by means time-averaged Navier-Stokes simulations. Three different conditions considered: zero velocity (stationary plate); with constant velocity; and acceleration. The nozzle-to-plate ratio inlet Reynolds number equal to 4 2 ? 104, respectively. objective research is...

We report on cavitation in confined microscopic environments which are commonly called microfluidic or lab-on-a-chip systems. The cavitation bubble is created by focusing a pulsed laser into these structures filled with a light-absorbing liquid. At the center of a 20 microm thick and 1 mm wide channel, pancake-shaped bubbles expand and collapse radially. The bubble dynamics compares with a two-...

The flow and heat transfer in two planar impinging jets are investigated using Large-Eddy simulation and experiments. The jet Reynolds number based on nozzle width and centerline velocity is 500. Predictions are obtained of unforced jets in addition to forced cases in which periodic injection and suction is applied at the nozzle exit of each jet. The goal of the current effort is to characteriz...

Abstract The aim of this work is to study the effect different forms passive change in shape flow on intensity heat transfer impact jet. In work, a cycle experiments was performed investigate an axisymmetric jet flowing normally onto heated surface. located both natural conditions and during swirling (S = 0.4; 0.7; 1.0). It shown that target case chevrons has little character, but significantly...

Recent studies of impinging jet flows have shown that momentum exchange and heat transfer can be significantly improved if the jet flow is pulsed (Zumbrunnen, 1996). Moreover, when the jet holes are elliptical, jet free surfaces are formed into a helical structure. Upon pulsating the jet flow, the helical structure rotates and a strong twisting action can be imparted where the jet strikes a sur...

Cooling from impinging water jets in runout table (ROT) processing depends on the fluid flow and depth of water accumulated in the water pool that forms on the surface of the moving steel strip. This effect is investigated with a three-dimensional (3-D) computational model of fluid flow, pressure, and free surface motion for realistic banks of nozzles within the flow rate region of the ROT proc...

The merging of unstable liquid jets, approaching with high momentum, results in atomization and liquid mixing within a rapidly deforming impingement zone. The complex geometry and high index-of-refraction gradients that occur near the point of impingement present a particularly difficult environment for optical interrogation. X-ray based diagnostics are performed to determine the liquid mass di...

An experimental investigation of the primary breakup of round nonturbulent liquid jets in gaseous crossflow is described. Pulsed shadowgraph and holograph observations were made to determine the following breakup properties: primary breakup regimes, conditions required for the onset of ligament and drop formation, ligament and drop sizes along the liquid surface, drop velocities after breakup, ...