Creating a functional model of a jet engine to serve as a testbed for mechanical engineering students' capstone designwork

A gas turbine is an internal combustion engine that converts natural gas or other liquid fuels to mechanical energy, to drive generators or to provide the energy in water desalination or in petrochemical plants. Jet engines are gas turbines optimized to produce thrust from the exhaust gases. The design of jet engines involves all of the fields of mechanical engineering, but thermodynamics, heat transfer and vibrations are of particular importance to the engine design. In this paper, we present the work done by a group of senior mechanical engineering students as part of their MEEN 404 experiment design course project. Students were asked to slightly modify an open-source simplified jet engine CAD model for 3D printability, build and test the 3D printed functional model in different compressor and turbine configurations. For that, the students had to go through the entire design process, from functions through requirements, through alternative designs to be able to integrate the newly modified parts into their testbed. They had to equip the system with all the necessary sensors and instrumentation to control and monitor the engine while conducting many tests to study the cost, efficiency, and performance over a range of parameter values and environmental conditions such as the number of blades, blade angle of attack, and outlet nozzle size. This project was a good tool to promote student's engagement and development, advance their critical thinking, and improve their problem solving and leadership skills. The project was also of a great help to students in understanding many mechanical engineering topics covered in other classes, especially after being complemented by a workshop hosted by General Electric (GE) at Qatar Science and Technology Park, where students received a hands-on training session on regular maintenance work carried out on aircraft engines.