Analysis of aerodynamic characteristic on cylinder exhaust of pneumatic frictional clutch

The pneumatic frictional clutch is one of chief devices on the mechanical processing apparatus, thus its aerodynamic characteristic during normally working and the compressed air exhausting is discussed. Considering the effect of the back-moving spring in the cylinder on exhausting, and four cases of sonic or subsonic exhaust with constant volume or varying volume, the mathematical model and numerical simulation program is presented. The results of the verified experiment carrying on the experimental platform of the mechanical press of type JH23–63 shows that the analytical results is in a good agreement with the experimental results, with the maximum and average of relative error less than 10.1% and 4.9%, respectively. The increase of the speed and maximal speed at the nozzle as well as the exhaust time vary with the increase of the initial pressure in a cylinder. Below the given error range, the aerodynamic characteristic such as the pressure fluctuation, speed at the nozzle and exhaust time can be easily analyzed by using the presented mathematical model and numerical simulation program.