A New Approach in Control Valve Design With a New Hybrid Flow Characteristic
A control valve is often required to be designed for different kinds of flow characteristics, depending on the process to be controlled. The flow characteristics refer to the sensitivity of the valve spindle movement or opening to the increase in the flow.
In this paper, a new hybrid flow characteristic is explained. Generally, flow characteristics are achieved by various valve trims or shapes of the plugs to be designed. The challenge lies in the design of the shape of the valve trim to achieve the required flow characteristic. Often, many iterations of design, manufacture and testing are done, and this cycle is repeated to achieve the flow characteristic. In this paper, a novel iterative method is demonstrated to achieve not only the above flow characteristics, but also their new S-shaped flow characteristic derived by the author. A new empirical relation for the flow coefficient ‘K’ is derived, which is verified by CFD analysis. Further, after the design, the valve can also be virtually verified by CFD analysis.