DEVELOPMENT AND APPLICATION OF STAGNATION PRESSURE PROBE FOR DUSTY GAS MEASUREMENTS

The design, development and application of a fast response probe for measuring gas phase pressures under dusty flow conditions are described. Measured results for this probe, historically designated as the ''Snob'' probe, demonstrate satisfactory resolution of past limitations on output performance. The present vented Snob probe incorporates three transducers in a single probe body to measure static, total, and total-static differential pressures. The vented nozzle design allows for long duration testing without cavity plugging difficulties while measuring total pressures to within 1% accuracy. Measured data obtained to date demonstrate that the current ''tri sensor Snob'' performs satisfactorily over a range in a dusty flow environment (rho(dust)/rho(pair) less than or equal to 3) extending from high shock overpressure conditions (Delta P similar to 100 psi) to low velocity flows (2-5 fps). Performance validation results are presented herein as obtained from a series of dusty flow experiments performed in a high pressure shock tube and a low speed wind tunnel designed to investigate dust sweep-up phenomena. (C) 1995 American Institute of Physics.