Embedded Files
Compressor
Compressor
PLA 3D printed
Combustor
Combustor
304 stainless steel
Turbine & Shaft housing
Turbine & Shaft housing
304 stainless steel
Nozzle
Nozzle
304 stainless steel
Test Run
Test Run
From the operation analysis, we got our idle point at around 14,000RPM, 900K.
From the operation analysis, we got our idle point at around 14,000RPM, 900K.
Therefore, the prototype engine could run and self-sustain, if we accelerated it smoothly to this state. We used pressure air as our acceleration source, LPG as our fuel source, and arc generator as our ignition source.
Test outcome
Test outcome
At the beginning of the acceleration, the jet ran smoothly; the fuel rate and temperature values were close to our estimation.
At the beginning of the acceleration, the jet ran smoothly; the fuel rate and temperature values were close to our estimation.
However, at the point, 9000 RPM, EGT = 723K, the pressure of our starting air supply dropped significantly that it could not provide enough air to further accelerate the jet. The pressure air source we use to start the engine was not powerful and sustainable enough to accelerate our jet to the designed idle point. Hence, with this setup, the jet could not run successfully.
Next, we changed to use the larger pressure air source.
Next, we changed to use the larger pressure air source.
This air source can supply up to 50 atm pressure. However, we still could not reach the idle point since this air supply was extremely hard to control. The air pressure for this source might be too high, possibly destroying our prototype. In addition, the air flowing direction was so chaotic that it turned the compressor in the wrong direction.
small air supply test run
small air supply test run
high pressure source valve. 50 atm. Huge!
high pressure source valve. 50 atm. Huge!
Conclusion
Conclusion
- In order to start this jet, we need a medium air source to accelerate the jet to the design idle point.
- The material of the compressor stage should be changed to aluminum, since the heat will transfer from the turbine to compressor through the rotation shaft. This will cause large deformation to the compressor and make jet engine malfunction.
Acknowledgment
Acknowledgment
This is an undergraduate project for around two years. The team members are my college classmates: Li Xuan, Lin Po Chuan, Albert Zhou and Te Hsuan Chung . They all devoted themselves to this project and really pushed it forward.
During the research and development period, we gained tremendous support from our department, aerospace engineering in NCKU. Prof. Li Yueh-Heng supported us in experiment resources and assisted us with his seasoned experience. Prof. Chen helped us in CFD simulation and the thesis of fluid dynamics. In addition, we appreciated all the well-experienced advice from other professors that leaded us to consider different aspects which we never though of.
Other students in our department gave us generous hand as well. Zhung Yu Qun, Chen Chia Chun, provided guidance to the driving motor installation, graduate student, Chen Wei Han provided high quality 3D printing service to us, and Jhang Wei Ting supported us with abundant funds as well as valuable discussions.
While we could not run this prototype engine successfully, I believe that by solving the two main problems, compressor material and starting air source, we could build a self-sustaining micro jet engine that is fully designed and manufactured by ourselves.
Google Sites
Report abuse