Research Initiation Awards: Ignition and Combustion Phenomena of Laser-Ignited Baron Agglomerate at Elevated Pressures

研究的目的是研究环境压力对硼团聚体着火延迟时间和燃烧时间的影响。在这项研究中，安装在高压燃烧室内的探针支撑的硼团聚体被二氧化碳激光点燃。激光点火技术和高压燃烧室的使用将允许环境压力和氧化剂摩尔分数的变化。在点火和燃烧过程中，将使用近红外双色高温计测量激光点燃的硼团聚体的表面温度。与双色高温计配合使用，宽带辐射计被用来记录硼团聚块发射的辐射。根据双色高温计和宽带辐射计的时间输出，可以确定硼团聚体的点火温度、点火延迟时间和燃烧时间作为环境压力和氧化剂摩尔分数的函数。在能量密度评估的基础上，硼浆比传统喷气燃料具有显著的优势。该项目将提供在1到20atm的工作压力范围内对高性能吸气式发动机的典型操作压力范围内的硼颗粒团聚燃烧速率的实验测定。

The objective of the proposed research is to study the effect of ambient pressure on the ignition delay time and the burning time of boron agglomerates. In this investigation a probe- supported boron agglomerate mounted inside a high-pressure combustion chamber is ignited by a CO2 laser beam. The use of the laser ignition technique and high-pressure combustion chamber will permit the variation of the ambient pressure and oxidant mole fraction. Surface temperature measurements of the laser-ignited boron agglomerate during the ignition and combustion events will be carried out using a near-infrared, two-color pyrometer. In conjunction with the two-color pyrometer, a broadband radiometer is used to record the radiation emitted by the boron agglomerate. From the temporal outputs of the two-color pyrometer and the broadband radiometer, it is possible to determine the ignition temperature, the preignition delay time and the burning time of the boron agglomerate as function of ambient pressure and oxidant mole fraction. Boron slurries have a significant advantage over conventional jet fuels when evaluated on an energy-density basis. This project will provide experimental determination of boron particle agglomerate burning rates in the operating pressure range of one to 20 atm, typical of high-performance air- breathing engines.