A new type of pulsed water jet, which uses principles of self-resonance to create pressure fluctuations, is now being developed. The advantages of pulsing to improve the erosive action of a jet—by interrupting the flow, hence using the water hammer impact stress created by each individual slug—have long been appreciated by the users of water jets for cutting and cleaning applications. Of severa...

The Discussers congratulate the Authors for their relevant work. The paper provides interesting results of CFD simulation of turbulent circular jets impinging vertically on a flat plate. Three different models were used, the realizable kmodel, the kSST model, and the RSM model, and compared to experimental data from Rajaratnam et al. (2010) and Giralt et al. (1977). Many characteristics of the ...

Quenching cooling rate of rotary hollow cylinder by one row of water impinging jets has been experimentally studied. Water jets (d = 8 mm) with sub-cooling 55 to 85 ◦C and Reynolds number 8,006 to 36,738 impinged over rotary hot hollow cylinder (rotation speed 10 to 70 rpm) with initial temperature 250 to 600 ◦C. Impingement impact angle of row of jets varied between 0 to 135 ◦ and jet-to-jet s...

We use a microfluidic flow-focusing device with integrated electrodes for controlling the production of water-in-oil drops. In a previous work, we reported that very long jets can be formed upon application of AC fields. We now study in detail the appearance of the long jets as a function of the electrical parameters, i.e., water conductivity, signal frequency, and voltage amplitude. For interm...

Similarity solutions for laminar two-fluid jets and wakes are derived in the boundary-layer approximation. Planar and axisymmetric fan jets as well as classical and momentumless planar wakes are considered. The interface between the immiscible fluids is stabilized by the action of gravity, with the heavier fluid, taken to be a liquid, placed beneath the lighter fluid. Velocity profiles for the ...

The interaction of a laser-induced cavitation bubble with an elastic boundary and its dependence on the distance between bubble and boundary are investigated experimentally. The elastic boundary consists of a transparent polyacrylamide (PAA) gel with 80% water concentration with elastic modulus E = 0.25 MPa. At this Evalue, the deformation and rebound of the boundary is very pronounced providin...

Confined plunging jets are investigated as potential outfalls for the discharge of desalination brine. Compared to offshore submerged that rely on momentum induce mixing, released above water surface utilize both and negative buoyancy. Plunging also introduce air into column, which can reduce possibility hypoxic zones. In contrast unconfined jets, confined include a confining tube, or downcomer...

The mixing characteristics of coolant air jets with the hot gas exiting the gas turbine combustor’s primary zone is of major importance to the combustor exit temperature profile. In the present work, a three dimensional numerical simulation on the basis of the finite volume method was developed. The aim was to investigate the penetration and mixing characteristics of directly opposed rows of co...

The one-phase flow and the two-phase flow in a fluidic element are investigated by measuring Reynolds stress distributions of the main jets using the laser Doppler velocimeter. In the one-phase flow, a water flow jets from a main nozzle into water and in the two-phase flow, a water fiow jets into air. Some results with the one-phase flow are as follows. When either of the two control ports is c...

When scientists speak of a “jet” they are usually referring to a fast flowing column of material, typically air or water. These jets range from the mundane, like water rushing out of a hose, to the exotic, such as the relativistic plasma jets that beam out from quasars or monster black holes. A turbo-jet, for example, pushes an aircraft forward using the supersonic thrust of air that streams ou...