Experimental measurement of combustion instabilities in Rijke-Zhao tubes

• Main Author: Chow, Zhi Hao.
• Other Authors: School of Mechanical and Aerospace Engineering
• Format: Final Year Project
• Language: English
• Published: 2012
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/50932
• Institution: Nanyang Technological University

This project aims to investigate the onset and selection of combustion-excited oscillations in uniquely configured combustion systems through experimental approaches such as thermal imaging and flow visualization. The insights gained on the behavior of such combustion systems can be used in future researches to develop control methodologies to minimize and eliminate combustion instability, or to improve efficiencies in applications such as industrial dryers and engine systems. In this paper, the theoretical concept of pulse combustion will also be explained and demonstrated. The experimental set-up consists of Rijke-Zhao tubes of various configurations, being placed vertically above a flame. The Rijke-Zhao tubes are made of quartz and they are Y-shaped, with configurations varying in terms of the branch lengths and angles. High speed camera at 20 frames per second (fps) was used to capture flow motion within the quartz tubes, while infrared camera was used to display the temperature distribution. To measure the pressure field within the tube, two arrays of microphones were strategically positioned along the upper branches. Finally, a flow anemometer and a K-type thermocouple were used to measure the flow velocity and flow temperature at the ends of the branches respectively. The results gathered were tabulated and analyzed.