Accession Number : AD0614378

Title :   END-WALL HEAT-TRANSFER EFFECTS ON THE TRAJECTORY OF A REFLECTED SHOCK WAVE,

Corporate Author : CALIFORNIA INST OF TECH PASADENA GRADUATE AERONAUTICAL LABS

Personal Author(s) : Sturtevant,Bradford ; Slachmuylders,Erik

Report Date : 30 OCT 1963

Pagination or Media Count : 7

Abstract : The trajectory of a reflected shock wave has been measured near the end wall where the motion is perturbed by the displacement effect of heat transfer to the wall. In this experiment an x, t diagram of the reflection of an M = 4.08 shock wave was constructed by measuring shock arrival times with small probes. The parameter that measures the (negative) displacement thickness of the end-wall thermal layer, a 'Reynolds number' R based on the shock velocity, the time after reflection, and the thermal diffusivity was varied between 9 and 600. In this range the measured deviation of the shock trajectory from ideal varied from 11/2 to 17 shock thicknesses. The shock velocity was determined by differentiating a least-squares fit of the data to a fourth-order polynomial in 1/sq. rt. R. In the range of the experiments the shock accelerated from a velocity that was 20% below ideal to one that was within 4% of ideal. Experiment agrees with boundary-layer theory above R = 150 for the shock trajectory and above R = 25 for the shock velocity, and implies that the exponent of the power-law dependence of the thermal conductivity on temperature is 0.81 = 0.02. The small deviation of the shock velocity from boundarylayer theory predicted for R < 100 by higher-order theory is not observed, though since this theory falls just within the estimated experimental error this result is somewhat qualified. In any case, the unexpected agreement with first-order theory at small R indicates that molecular effects, such as temperature jump, do not play a large role when the shock is more than ten shock thicknesses from the end wall. (Author)

Descriptors :   (*SHOCK WAVES, TRAJECTORIES), (*REFLECTION, SHOCK WAVES), (*HEAT TRANSFER, SHOCK WAVES), THERMAL DIFFUSION, BOUNDARY LAYER, REYNOLDS NUMBER, LEAST SQUARES METHOD, PERTURBATION THEORY, NONEQUILIBRIUM FLOW, THERMAL CONDUCTIVITY

Distribution Statement : APPROVED FOR PUBLIC RELEASE