Abstract

Interferometric Rayleigh scattering (IRS) is a powerful laser diagnostic technique. Its capability to capture the Rayleigh scattering spectrum makes it suitable for simultaneous multi-parameters measurement of flow such as velocity and temperature. By incorporating a virtually imaged phased array (VIPA) into the IRS system, it becomes possible to measure the Rayleigh scattering spectrum of flow along one dimension with millimeter-level spatial resolution. Accordingly, this thesis focuses on the development of 1D IRS for quantitative multi-parameters measurement and its application to internal combustion engine.

First, this thesis advances 1D IRS to achieve spatially resolved temperature measurements in air flows—thereby enabling simultaneous quantitative velocimetry and thermometry. A demonstration of simultaneous temperature and velocity measurements in an air flow is provided, followed by a discussion of the resulting temperature and velocity profiles, as well as the measurement accuracy and precision.

Second, this thesis applies 1D IRS in conjunction with a high-speed burst-mode laser to study the flow velocity and spectrum inside a prechamber throat at elevated pressures without combustion. Through this high-speed 1D IRS approach, key characteristics such as velocity of the prechamber flow are unveiled to enhance the performance of prechamber.

Lastly, 1D IRS is implemented in prechamber mounted on a running engine, trying to achieve high spatial and temporal resolution measurements of velocity inside the prechamber during the engine running.

Biography

Xinguang Luo joined the ME program in the PSE division at KAUST in 2019. He previously earned his bachelor's degree from Huazhong University of Science and Technology in 2016 and master's degree from Xiamen University in 2019. During his PhD, his research mainly focused on laser diagnostics, particularly interferometric Rayleigh scattering for velocity measurements in reactive and non-reactive flows.

Zoom link: https://kaust.zoom.us/j/95484822979