Rotary Valve

 

 

 

 

For the development of the rotary valve, the author thought that the most efficient way to use it in the engine in study would be considering that the opening on the head of the cylinder has the shape of a rectangle and the corners are close to the limit of the cylinder, as shown in bellow in (Figure 1). This way the intake area has the maximum possible value so it is more efficient.

 

 

 

 

 

 

 

 

 

 

 

 

Another aspect that is necessary to take in consideration, is that the opening and closing time of the rotary valve must be similar to the poppet one. This means that it should open a bit later and close a bit earlier than the poppet valve because of the gap between the valve and the cylinder head. With this aspect, the valve opens at 355º and closes at 570º.

 

The equations used for the calculation of the intake area of the rotary valve are,

 

• Position 1: 

 

                                                                                                                                        (1)

 

• Position 2:

 

                                                                                                                                        (2)

 

 

• Positions 3:

                             

                                                                                                                                        (3)

 

 

Where l is the length of the cylinder entrance,  d the position of the valve, h is the height of the entrance and m is the height of the valve opening.

The graph obtained using this equations is shown below,