The Experimental Study Of Algae Mass Transfer And Biological Fouling Organisms In Laminar Flow Channel

Since our country sets targets of development for deep-sea, the marine engineering will develop rapidly. The accompanying question that the marine organism adheres to the devices for marine engineering will be more severe. The starting point for solving that question is near-wall regions. That is studying the mechanism of plankton passing in and out and staying the surface, especially the transport phenomena of plankton near the boundary layer. Besides the transport phenomena of particulate, the key to solve the problem also needs the coupling of hydrodynamic character and the characteristics of biological movement for marine organism. In this context, this research establishes experimental systems and method in terms of solving the above problems.In order to obtain algal cells transport law,we took Coscinodiscus cells as the model,and advanced experimental techniques is used to quantify the phenomenon of experimental observations.The main results are as follows:(1).According to the theory of fluid mechanices,coscinodiscus cells and optical measurement requirements,we establish laminar channel.The laminar channel can ensure a stable flow within laminar flow.Reynolds Number is 239.The dimensions of the observing surface is 350mm x 30mm x 20mm.the boundary layer is 3mm,which is larger than the 50um diameter of the Coscinodiscus cell.(2).The system of the digital holographic is designed to measure and analyze the motion parameters of the particle/coscinodiscus cells.Because of the different lens,observation area is 3mm x 3mm x 20mm and 6mm x 6mm x 20mm.The fps is 150Hz.(3).The transport data of the 50um particle and the coscinodiscus cells in the laminar channel,which including spatial orientation,displacement,velocity,trajectory and so on.Also,the posture of the coscinodiscus cells is recorded.(4).Coscinodiscus is more dense than seawater.Because of the gravity,in the transport process with low velocity.conscinodiscus close to the wall.In the stable flow,the trajectory is a straight line.wheal,in the near-wall area,the trajectory is a curve. And the changes of its posture is very clear.