Accession Number:

ADA167360

Title:

Wind Tunnel Test of the Modified Goldschmied Model with Propulsion and Empennage: Analysis of Test Results

Descriptive Note:

Final rept. 3 Mar 81-30 Nov 82

Corporate Author:

GOLD SCHMIED (FABIO R) MONROEVILLE PA

Personal Author(s):

Report Date:

1986-02-01

Pagination or Media Count:

115.0

Abstract:

An extensive test program was carried out in DTNSRDCs 8x10 low-speed wind-tunnel for experimental verification of the integrated hull boundary-layer controlpropulsion lighter-than-air design. The 1957 Goldschmied wind-tunnel model was overhauled with a new suction-slot inlet configuration, a suction propulsion fan, a new aftbody and a tailboomempennage assembly. The fan air power coefficient of the operational model with empennage ranged in steady flight from 0.0130 free transition to 0.0155 transition tripped at 10 length at the volume Reynolds number of two millions. Considerable excess thrust could be generated with an average incremental propulsive efficiency of 72. As compared to wind-tunnel tests of conventional streamlined bodies with empennage at exactly the same volume Reynolds number, the integrated design offers 50 less equivalent drag for both free and tripped transitions. The empennage provided neutral static stability over the complete test range of 8 degrees the ratio of total fin planform over volume equivalent was 0.404. It was found that efficient and stable BLC could be achieved only by the combination of Ringloeb cusp at the slots leading-edge with suction flow and with the presence of the tailboom. The fan or pump design is an essential part of the system design a procedure was developed for determining the optimum fan design parameters from the vehicles wind-tunnel test data. As an example, a tested NACA axial rotorstator stage could be employed with 93 adiabatic efficiency for the vehicle with empennage and tripped transition. Keywords Airships Aerodynamics Hydrodynamics Jet propulsion.

Subject Categories:

  • Aerodynamics
  • Lighter-than-air Aircraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE