Investigation Of Microstructure Surface Effect On Biofouling

Biofouling is common in many industrial fields,which effects the normal operation of water equipment,and shortens its service life.Toxic substances such as tin and mercury are released during the utilization of traditional release antifouling coatings to poison microorganism to avoid biofouling,however,this seriously damages the ecological environment.Inspired by the surface structure of shark skin,a new type of antifouling material based on the microstructure surface has attracted considerable attention.In this paper,for the antifouling characteristic of microstructure surface,two-dimensional physical model that microorganism moves on the microstructure surface and three-dimensional microchannel model of microstructure surface are established.Flow field characteristics of near-wall region and area around microorganism are analyzed with numerical simulation.The antifouling and drag reduction characteristics of different microstructure surfaces are compared.The main contents are as follows:(1)The physical model that microorganism moves on the microstructure surface is established,and the numerical simulation of microorganism in the flow fields is carried out with FLUENT to investigate the microorganism motion characteristics.Strain rate and shear stress of smooth surface and microstructure surface are compared,and the kinematic and dynamic variation regularity microorganism experienced in different height and flow field are analyzed.Microstructure surface effect on attachment of microorganism is explored from the perspective of fluid mechanics.(2)A 3D microchannel physical model with microstructure surface is established,and numerical simulation of flow field in the microchannel is performed.Flow field in the near-wall region is examined,and the hydrodynamic characteristics of smooth surface and microstructure surface are compared.The inherent mechanism of antifouling on microstructure surface is discussed.Effect of microwell gap,microwell radius and arrangement mode on near-wall region are examined by analyzing kinematic and dynamic characteristics of fluid,which can determine the best surface model of antifouling and drag reduction.