Analytical Study of Mixed-Flow JT8D Exhaust Emissions Measurements for Fixed-Probe Requirements.

摘要

A method is outlined to optimize the shape,size,and location of fixed probe for acquiring representative emission samples from the exhaust of a mixed-flow JT8D-11turbofan engine. Families of geometric shapes and mutually exclusive probe configurations are overlaid upon a 177-point traverse grid. A significance ratio is calculated and used to rank results. Representative and nonrepresentative areas of the exhaust plume are defined. Probe configurations are overlaid upon the traverse grid and ranked to obtain a representative configuration. An area of the JT8D exhaust plume suitable for acquiring representative emission samples was found which reduces the overall 177sample points to 20sample points. (Author)