| Studies have shown that aquatic organisms in the fluid medium motion, its special skinstructure can change dynamically based on fluid load to achieve drag reduction function.This article is inspired by the above phenomenon, bases on similar principles of bionics,designs and prepares a bionic structural heterogeneous composite materials, the compositematerial is constituting the layers of different material properties, the use of iron as a basematerial is used to with stand the pressure, the use of flexible polyurethane as a surface layermaterial is used to pass the fluid pressure, prepared a new type of bionic structuralheterogeneous composite materials, which achieved effective control of the fluid medium.Studies have shown that although bionic heterogeneous composite materials with thisstructure applications in fluid machinery-pump products which synergistic results issignificantly, however, we found in the actual application process that this bionic structuralheterogeneous composite materials has not wear-resisting and flaking off, this article mainlystudies on the wear resistance, mechanical properties of surface layer material of bionicstructural heterogeneous composite materials and its interface with basal material mechanicsperformance. The goal is to study wear resistance and shear resistance, doing optimizationon ratio, second curing time of the surface layer material and interface morphologyparameters of based material, doing studies on the control mechanisms of bionic structuralheterogeneous composite materials for the fluid medium by using of flow visualization tests,the above research provides technical assurance for full application of all fluid machineryfluid as the working medium or transport vehicles in a fluid medium run about the newmaterials, this article studied the following areas and drew the following conclusions:1. Experimental study on mechanical properties of bionic structural heterogeneouscomposite materialsWhen design and preparation of bionic structural heterogeneous composite materials, ishould consider elasticity/abrasion resistance of the surface layer material and mechanicalproperties of the interface, which combined the surface layer material with the base material.the elasticity/abrasion resistance of the surface layer material is closely related to the ratio/secondary curing time of the surface layer material, studies have shown that components A,B ratio100:12, secondary curing time eight hours, the elasticity/abrasion resistance of the surface layer material is optimal; In addition to ratio of the surface layer material, the basematerial′s surface structure of bionic structural heterogeneous composite materials seriouslyaffected resistance to stretch/resistance to shear of the interface.2. Defection detected for bionic structural heterogeneous composite materialsUltrasonic wave NDT proved it′s feasible and effective that using bidirectionaldetection to judge defection for bionic structural heterogeneous composite materials.3. The main control mechanism for fluid medium of bionic structural heterogeneouscomposite materials(1) The bionic structural heterogeneous composite materials dynamic control the fluidmedium by the surface layer material′s elastic deformation and the coupling between thesurface layer material and the base material with bionic non-smooth structure, the elasticdeformation of surface layer material absorbs portion energy, thus, it reduces thedisturbance/spread/developing of the fluid medium and to achieves reattachment stabilitywith fluid medium in the trail, it reduces the negative pressure in the trail, achieves thepurpose of reducing resistance of pressure difference.(2) The bionic structural heterogeneous composite materials conforms to pressurechanges of fluid medium by the surface layer material′s elastic deformation and the couplingbetween the surface layer material and the base material with bionic non-smooth structure, itstabilizes fluid turbulence of its surface, it slow power dissipation down by reducing speedand density of vortex in the trail, thus, it researches control mechanisms for fluid medium,achieves the purpose of drag Reduction and efficiency enhancement. |
