We’ve written before about the fluid power research projects coming out of the Center for Compact and Efficient Fluid Power. Ten new research projects have recently been selected for funding. One student benefiting from the funding is Chen Zhang, a student at the University of Minnesota who is working on the Free Piston Engine Based Off-Road Vehicles project.
Education and Career
Chen Zhang is a fifth year Ph.D. student working at the University of Minnesota, Twin Cities Campus. He plans to give his final defense next February and continue his research project, the Free Piston Engine, for another one or two years as a postdoc. At the same time, he will also hunt for a position in the academic world and continue his research even further.
For his career plan, he will try to thoroughly investigate the free piston engine based hydraulic pump technology and manufacture a prototype within five years. In the next 10 years, Chen plans to further promote this technology and introduce it into both on-road and off-road automotive applications. He hopes the free piston engine hydraulic pump will be the dominant hydraulic power source for the off-road heavy machinery after his 20 years of endeavors and efforts.
The goal of his current research is to investigate the design, control and testing of free piston engine (FPE) based off-road vehicles to improve their fuel efficiency and reduce emissions. This is achieved by controlling the hydraulic FPE in real-time to generate the required pressure and flow rate as a modular and efficient power source and designing the appropriate hydraulic actuation system for both linear and rotary motion to reduce or remove throttling losses.
The project will address the top three strategic priorities of the CCEFP:
1) increasing energy efficiency of fluid power;
2) improving and applying the energy storage capabilities of fluid power;
3) reducing the environmental impact of fluid power.
The first priority is achieved by improving the thermal efficiency of the prime mover with the hydraulic free piston engine and improving the efficiency of the hydraulic actuation by reducing throttling losses enabled by the modular and on demand fluid power source. The second priority is achieved by using liquid fuel as the energy storage whose energy density is the order of magnitude higher than a battery and converting it into fluid power in real-time with high efficiency. This also opens up the opportunities for accommodating various liquid fuels due to the flexibility of the FPE. The third priority is achieved by reducing the greenhouse gas and other pollutant emissions with advanced combustion such as low-temperature combustion (LTC) enabled by the FPE.
Motivation for Choosing Engineering
To Chen, being an engineer means that you have sufficient ability to solve practical problems. In order to solve a practical problem, you have to understand the principles of the physical world, be able to pinpoint the essence of problem, and you have to possess the hands-on skill sets to eventually solve the problem. As a result, he not only sits in the front of the computer and conducts the simulation program, he also works in test cells and experiments with real world hardware.