Analysis and optimization of a butterfly valve disc

A butterfly valve is a type of flow control device, which is widely used to regulate a fluid flowing through a section of pipe. Currently, analyses and optimization are of special important in the design and usage of butterfly valves. For the analysis, finite element method (FEM) is often used to predict the safety of valve disc, and computational fluid dynamics (CFD) is commonly used to study the flow characteristics of valve. However, it is difficult to obtain accurate results for the optimization of butterfly valve due to the high non-linearities. For this reason, metamodels or surrogate model methods are extensively employed. This paper integrates metamodel with FEM and CFD analysis to optimize a traditional butterfly valve, where the weight of the valve disc is the design objective, and the strength safety of disc and the pressure loss coefficient of valve are constraints. Kriging model is employed as a surrogate model to formulate the objectives and constrains, and the orthogonal array is used as design of experiment to sample the computer analysis. The optimum results with the corresponding variable combinations for the valve disc are obtained easily by this method. Moreover, the structural and fluid analyses with the obtained optimum variable combinations are conducted again to verify the accuracy of the optimization method. The results demonstrate the capability and potential of this method, which integrates the Kriging model with FEM and CFD analysis, in solving the optimization of a butterfly valve.