Hands On Experience With A Turbojet Engine In The Thermal Science Laboratory Course

Thermal Science laboratory is the third course in the sequence of four mechanical engineering laboratories offered by the Department of Mechanical Engineering at North Carolina A&T State University. The course is one credit hour, meeting once a week for two hours. The course includes selected experiments on heat transfer and thermodynamics. In an effort to give students a combination of theoretical background and hands-on experience, a new experiment on gas turbine engine was introduced. This paper describes the experiences the students gained in this experiment. During this laboratory the students actually learned how to operate a turbojet engine, collected and analyzed the output data including thrust and efficiency, and related the experimental result to the theory learned in the thermodynamics course. This experiment complemented the thermal science laboratory course and fully integrated some aspects of thermodynamics and enhanced the student’s learning process. The turbojet engine used in the laboratory was a table top arrangement of a single-stage radial-flow compressor, a single-stage axial-flow turbine, and a reverse-flow annular combustion chamber turbojet engine. The engine is of a single shaft design. Both the compressor and turbine rotate on the same shaft at the same speed. The turbojet engine was equipped with a data acquisition system to monitor engine speed, exhaust gas temperature, fuel flow and thrust. Introduction This experiment is designed to give the students a hands-on experience with a jet engine, and to directly relate the mechanical device to the theory learned in a typical thermodynamics course. This paper describes the experiences the students gained in the areas of propulsion and gas turbine engines. The laboratory introduces the students to the basic principles of the gas turbine engine. During this experiment the students actually learn how to operate a jet engine, collect and analyze the output data and relate the result to the theory learned in the thermodynamics courses. The broader educational objectives are to improve the students’ understanding of thermodynamics, to help them integrate this knowledge with other subjects, and to give them a better basic understanding of how a jet engine works. P ge 13662.2 Equipment The gas turbine experiment was conducted using the SR-30 turbojet engine manufactured by “The Turbine Technologies, LTD”; a cut-away view of the SR-30 model gas turbine engine is shown in Figure 1. and its major engine components are shown in Figure 2. The SR-30 turbo jet engine is comprised of: 1. A single stage axial flow turbine, 2. Radial flow compressor and 3. Reverse flow annular combustion chamber. 4. The engine is of single shaft design. 5. Both the compressor and turbine rotate on the shaft at the same speed. 6. The engine is fully throttleable from an idle speed of 45,000 rpm to a maximum speed of up to 90,000 rpm. Figure 1. Cut-Away View of Turbine Technologies SR-30 Gas Turbine Engine 1