Design And Experimental Study Of Manifold Based On Constructal Theory

The constructal theory has been proposed to be widely used in the optimization of various fluid pipelines,most notably the optimization of the volume-point model.Based on the optimization method of this model in this paper,a new type of manifold is proposed and designed to solve the problem of large inlet and outlet pressure drop and small outlet flow in common subsea manifolds on the market.The research of constructal theory has shown that the optimized flow channel structure is similar to the natural tree shape,so the research of this paper focuses on the preliminary exploration and optimization of the tree-shaped manifold.The tree structure studied in this paper including the plane tree structure and the three-dimensional tree structure.The plane tree structure also includes plane symmetrical tree structure and plane asymmetric tree structure.The manifold structure used in the simulation analysis and experimental study is a symmetrical tree-shaped manifold and a space tree-shaped manifold.Thesimulation results show that the flow lines in the new type manifolds are more orderly than the traditional manifolds,and the pressure drop of the inlet and outlet is smaller than that of the traditional manifolds in the same initial condition by ANSYS.The experimental research on three kinds of manifolds was carried out on the parallel pump platform,and the experimental results show when used as a water segregator,two new manifold corresponding to the pipeline characteristic curve is more gentle,and under the same flow rate,pressure drop is smaller.Four pumps running in parallel,under the same flow rate,the pressure drop reduction rate of the new type of water segregator than that of the traditional manifold is between 5%and 30%;When used as a water collector,under the same pump operating frequency,both the inlet and outlet pressure drop of the sump and the outlet flow rate,the two new type manifolds have better performance than the traditional manifolds,and the corresponding equivalent pump efficiency also shows that when four pumps are operated in parallel at 80%-100%of the rated operating conditions,the efficiency of equivalent water pumpcorresponding to the tree-shaped manifolds is 8.4%higher than that of the traditional one.,the efficiency of the largest growth rate of 9.1%at 46HZ.At 42HZ,the minimum value of the efficiency growth is 5.9%,and the efficiency increase is 7.8%under rated conditions.The equivalent pump operating efficiencies corresponding to three-dimensional manifolds is higher than that of the conventional manifolds increased by 4.2%.the efficiency of the largest growth rate of 6.97%at 42HZ.At the rated operating conditions,efficiency growth rate is 1.5%,which is also the minimum efficiency growth.