Accession Number:

AD0614378

Title:

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

Descriptive Note:

Corporate Author:

CALIFORNIA INST OF TECH PASADENA GRADUATE AERONAUTICAL LABS

Report Date:

1963-10-30

Pagination or Media Count:

7.0

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 112 to 17 shock thicknesses. The shock velocity was determined by differentiating a least-squares fit of the data to a fourth-order polynomial in 1sq. 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

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Distribution Statement:

APPROVED FOR PUBLIC RELEASE