University of Minho
Department of Mechanical Engineering
MIEMEC | Integradora VIII
Trapezoidal Rotary Valve
Trapezoidal Rotary Valve
The trapezoidal rotary valve has the same aspects as the rotary valve that need to be taken into account, the only exception is that one of the sides of the opening in the cylinder and in the valve are going to be smaller, as shown in Figure 1.
Because of the difference between the sides of the valve it is necessary to add a few more positions, which means more equations. The first step to take is to calculate the areas (area of the cylinder opening) and (area of the valve opening), so we have:
(1)
(2)
-
Position 1 (x<b):
(3)
-
Position 2 (b<x<a):
(4)
-
Position 3 (a<x<e):
(5)
-
Position 4 (e<x<e+(a-b)):
(6)
-
Position 5 (e+(a-b)<x<(a+e)):
(7)
Introducing this equations in the Excel, the generated graph is shown below,
Figure 1. Trapezoidal rotary valve geometry
Figure 2. Position 1
Figure 3. Position 2
Figure 4. Position 3
Figure 5. Position 4
Figure 6. Position 5
Graph 1. Trapezoidal rotary valve intake area