Bond graph modeling of needle typed jet dispensing system driven by piezoelectric actuator

To dispense high viscosity micro-droplets accurately and speedily, and investigate the dispensing effects affected by system parameters, a kind of needle typed jet dispensing system driven by piezoelectric actuator is designed, whose bond graph model is also constructed. Combining piezoelectric actuator and needle typed jet dispenser, the system utilizes the piezoelectric actuator to vibrate the needle, which drives the droplets squirt from the nozzle. The system model validated experimentally is obtained by coupling variables from different energy fields, and sub-models of electrical and liquid-gas parts constructed following bond graph parameters in different dispensing channels. The simulations show that the jetting speed and volume depend on the drive voltage and gas-pressure linearly. And the dispensing speed also linearly relates to the needle vibration speed, and it means that the dispensing speed can be monitored indirectly by testing needle vibration.