Valve Displacement

Figure 11: Geometry of a blown open pressure-controlled valve showing effective areas $S_1, S_2, S_3$.

• Consider the double reed in a blown open configuration.

• Surface $S_1$ sees an upstream pressure $p_1$, surface $S_2$ sees the downstream pressure $p_2$ (after flow separation), and surface $S_3$ sees the flow at the interior of the valve channel and the resulting Bernoulli pressure.