Research On Orifice Jet In Mixing Conditions

The fluid phenomenon of jet is very common in engineering. The outlet conditions of nozzles have great effect on the spread of jet. The earlier researches on jet concentrate on that the fluid upstream of nozzles is totally developed pipe-flow. This paper studies the orifice jet in mixing conditions. The research indicates that the orifice jet in mixing conditions has many different points from the pipe jet.Focusing on the jet ejected from the orifices of different diameters and lengths, this paper studies the orifice jet when the fluid upstream of the orifices is in mixing conditions. The main purpose is to qualitatively study the effect of orifice diameters and lengths on the spread of the jet. On this basis, in solid-liquid system the spread of the orifice jet in mixing conditions is studied. This paper studies the spread of phosphorite plasm jet for different outlet velocities, different baffle distances and orifice diameters of 0.0105m , 0.021m and 0.032m. The axial distances and the longest radial distances are measured when the concentration decay is 5%. The measured range is x/D=6~64 and the outlet Reynolds for 1.2x104~39x 104. When the concentration decay is 5%, the experiential models are regressed for the axial distances and the longest radial distances with orifice diameters, orifice lengths, outlet velocities and baffle distances. Further provided theoretical basis for the design and rebuilt of the punched agitator.The punched agitator can develop the orifice jets in the course of stirring. The main difference between it and the conventional agitators is that there are holes of different diameters and distribution ratios in the paddles. Lots of the orifice jets areABSTRACTformed when fluid flow through the orifices and eddy diffusivity is intensified. Compared with the conventional agitators without holes in the paddles, the new-type punched agitator improves stirring efficiency, reduces stirring energy consumption and has extensive practical use when the orifice diameters and lengths are in a certain extension. The jets ejected from the orifices have a great importance in the process. The earlier research on punched agitator focuses on seeking the best hole-bored mode and hole ratio from the energy consumption point of view and not systematically analyzing the mechanism. This paper provides further theoretical basis for the design and rebuilt of the punched agitator and references for the orifice jet in other appliances.