Piezoelectric actuators offer fast response, high resolution, and low power use, which makes them a promising alternative to conventional thermal throttles and bang-bang solenoid regulation. However, effects such as hysteresis, creep, and temperature dependence must be understood and compensated. You will model, build up, and experimentally characterize a piezo-based flow control concept, and develop a control strategy for closed-loop mass flow regulation.
Your Responsibilities
- Review the state of the art in mass flow control for electric propulsion, including thermal throttles, solenoid-based pressure regulation, and piezo valves
- Research state of the art of piezo actuators and trade different architectures (e.g. stacked, amplified, piezo motors) for the given application
- Characterize the piezo actuator (stroke, force, hysteresis, creep, temperature behavior) and its effect on the valve’s flow area
- Assess the concept against typical electric propulsion requirements (flow range, leak rate, power consumption, operating temperature range)
- Build a physical flow model of the valve that links actuator stroke, inlet pressure, and gas properties to mass flow, covering the relevant flow regimes (e.g., choked and transitional flow)
- Integrate the actuator into a valve architecture and design a breadboard model
- Review existing test bench infrastructure with pressure sensors and a mass flow meter, adapt if necessary, and carry out flow characterization with inert gases
- Optionally, develop and implement a closed-loop control strategy (e.g., PID with hysteresis compensation) and evaluate its performance in terms of accuracy, resolution, response time, and stability
- Optionally, derive design recommendations for a flight-representative valve