Accession Number : AD0673109

Title :   INVESTIGATIONS OF FLOW PROPERTIES IN AN EXPANSION TUBE,

Corporate Author : BALLISTIC RESEARCH LABS ABERDEEN PROVING GROUND MD

Personal Author(s) : Spurk,Joseph H. ; Gion,Edmund J. ; Sturek,Walter B.

Report Date : JUN 1968

Pagination or Media Count : 32

Abstract : Early experimental investigations of expansion tubes, which incorporate unsteady expansions to produce high Mach number, high energy flow, have pointed to two major difficulties: (1) flow contamination; and (2) lack of flow uniformity. The tests reported, which include (1) measurements of the number densities of the major impurities Fe, CN, Cr; (2) pitot pressure measurements in conjunction with interferometric measurements of free stream density; and (3) stagnation heat transfer measurement; show that the extent of these difficulties is largely overestimated. The effect of a diaphragm cutting device for the secondary diaphragm (the uncontrolled bursting of the diaphragm is thought to be responsible for the difficulties experienced) is found to have an adverse effect on the flow properties. Preliminary results from an expansion tube with the secondary diaphragm supported by a 'nozzle plate' are, however, encouraging. (Author)

Descriptors :   (*SHOCK TUBES, AERODYNAMICS), SHOCK WAVES, HYPERSONIC CHARACTERISTICS, PERFORMANCE(ENGINEERING), ENTHALPY, STAGNATION POINT, REYNOLDS NUMBER, SIMULATORS, HEAT TRANSFER

Subject Categories : Test Facilities, Equipment and Methods
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE