In-cylinder wall temperature measurements using Thermographic Phosphors and Laser-induced Fluorescence Spectroscopy

点击翻译按钮获取中文摘要

The goal of this proposal is to obtain precise measurements of wall temperatures inside internal combustion engines with high temporal and spatial resolution. For this purpose, an optical non-contact surface temperature measurement technique called phosphor thermometry is employed. This method takes advantage of thermographic phosphors, whose spectral properties change with temperature. Based on the results of the first period of proposal, in-cylinder wall temperatures are to be determined with high sampling rates in order to monitor surface temperatures of individual cycles. These measurements are complemented by spatially and temporally resolved flame visualizations. Therefore planar laser-induced fluorescence of the OH-radical is employed, which is well suited for flame front visualizations. By the use of high-speed-lasers and-cameras wall temperatures and flame-wall-interactions are detected simultaneously with a temporal resolution of one degree of crank angle. Besides the validation of numerical simulations, the results will improve the understanding of component thermal stress, instationary heat-losses and flame-quenching in the vicinity of walls, which partly accounts for primary production of pollutants.