Mixing Characteristics Analysis And Structure Design Of Platelet Fluid Mixer

Platelet mixer,based on platelet device,is a novel-style static mixer.It can mix gases or liquids well through platelet micro-channels cross-bedded injection technology.The structures of the platelet fluid mixer are very simple than other mixers.It has no moving parts,and it can mix gases or liquids with different viscosity in a very small chamber.In this paper,the mixing characteristics in mixing chamber and mixing effect are analyzed.The influence of jet angle and the jet velocity ratio is considered.With the increase of jet angle,the flow state changes from the vortex movement to the tangential rotate movement gradually,and the mixing effect promote prominently as the flow state changes.The jet fluid join the main fluid in mixing chamber continuously as the main fluid rotates around the axis.The velocity between the main fluid and jet fluid is different,so there is shear stress between two kinds of fluids which is good for mixing process.Then the velocity ratio is considered.The uniformity of mixture ranges as the velocity ratio changes.The second order velocity slip boundary is considered to calculate the micro scale characteristic of flow control passages in platelet fluid mixer.The micro-scale characteristics of velocity distribution along the thickness direction and pressure distribution along the flow direction of control passages gradually become obvious as the Kn increase.The calculation methods are applied on the air/oxygen platelet mixer.Then the critical platelet thickness can be calculated which the micro scale characteristic should be considered in the analysis of mixing characteristics.The Finite Element method is applied to analyze the temperature distribution and thermal stress of the platelets.The thermal stress can not be neglect in design of platelet.So the structures of platelet should be designed after the analysis of thermal stress.For the situation,the structure can meet the requirement of thermal stress when the diameter of air passage and oxygen passage are 50 mm and 35 mm respectively.Finally,the platelet fluid mixer can be used as the pre-mixer of air-heater in engine experiment.The structure is designed according to the experiment condition based on the analysis results.The manufacture specification is also introduced.