HEAT-TRANSFER EFFECTS ON THE FREQUENCY-RESPONSE OF A PNEUMATIC NOZZLE FLAPPER

The dynamics of a pneumatic nozzle flapper are influenced by the heat transfer characteristics in the air chamber. In this paper the transfer function for a nozzle flapper is analytically derived considering the heat transfer. As a result it is shown that the system can be expressed as a second order time lag system. In the experiments, the frequency response tests have been conducted for different heat transfer conditions, and the heat transfer effect is clearly shown. The experimental data are in satisfactory agreement with the calculated frequency responses.