Turbine wheel study for turbojet engine

• Main Author: Yune, Sebastian Wei Kiat.
• Other Authors: School of Mechanical and Aerospace Engineering
• Format: Final Year Project
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/46161
• Institution: Nanyang Technological University

Nanyang Technological University (NTU) has grown her interest in developing, designing and manufacturing a turbojet engine at the institute level due to its high level of involvement in international UAV competitions. There are several Final Year Projects aim to explore the means to design and improve the turbojet engine at component level, such as the compressor, combustor and turbine. The turbojet engine is a turbo-machinery that utilizes the turbine to drive the compressor via extracted energy from the pressurized fuel-air mixture in the combustion chamber. The compressor pressurized the air from the free stream prior to the combustion chamber where the fuel will be mixed with the pressurized air, and burned at a high temperature. The cycle repeats itself and sums up the operations for gas turbine engine. The process can be described in the Brayton cycle. Analysis of the turbine stage performance of the engine requires specialized software. Concept NREC’s AxCent® is one such specialized software, whose capabilities and functions are extends beyond CFD runs to modifications to the engine dimensions. Two mini turbojet engines have been selected for the course of this project; KJ 66 from Artesjet and the SR 30 from Turbine technologies, which the 3D CAD profile have be acquired to assist the process of understanding the Concept NREC’s AxCent ®software for CFD runs and parameters modifications. Validations of the KJ 66 and SR 30 CFD runs will be conducted to ensure the reliability of the CFD run results. The detail experimental setup for the CFD runs has been listed in this report. The parameters of KJ 66 engine have been selected for studies to find the relation of the performances and parameters with support of theory. Once method for the CFD runs has been matured, the modification and improvement of SR 30 will be conducted with the aid of the software. All CFD runs have been conducted with the variation and modification of the parameters for both models of rotor blade to ease the study for the system. Most results have shown relations and trends with the theory found in the literature review. However there are some parameters that do not behave in the trends as the theory as suggested. Thus an in-depth analysis has been performed to ensure their validity. The Concept NREC support team has been sourced for assistance in these matters. It has also been found that particularly two parameters have adverse effect on the performance of the turbine rotor; exit absolute angle and tip clearance, with respect to the results obtain. The results have drawn conclusions that the SR 30 has limitation on further improvement and hence the re-design engine from scratch will be favoured for better performance engine.