Noise reduction for temperature-sensitive paint measurement contaminated by strong background radiation in a high enthalpy hypersonic tunnel

• 作者: Di Peng Xu Liu Lingrui Jiao Ziyan Li Xin Wen Chaokai Yuan Guilai Han Yunfeng Liu Yingzheng Liu Zonglin Jiang
• 来源期刊: 力学学报（英文版）
• 年，卷（期）: 2021,（1）
• 所属期刊栏目: RAPID COMMUNICATION
• 页码范围: 20-26
• 页数: 7页
• 语种: 英文

摘要

The strong background radiation in high enthalpy hypersonic shock tunnels has posed severe challenges for measurement using luminescent coatings.We proposed a solution for reducing background radiation from time-resolved temperature-sensitive paint(TSP)measurement in a hypersonic flow with Ma = 6.5 and T0 = 3525 K.The TSP was applied on an inlet ramp model,and the images were taken by a high-speed camera at 2 kHz under a modulated excitation.The strong background radiation led to a low signal-to-noise ratio and significant errors for the first half of the 130-ms test duration.Accordingly,three noise reduction methods were developed and evaluated based on temporal reconstruction,spatial reconstruction and robust principal component analysis(RPCA),respectively.The RPCA method showed the best performance that successfully recovered high-quality TSP data for a majority of test duration(t≥40 ms).