The problem of roughness drag at supersonic speeds

Methods of estimating roughness drag at supersonic speed

Theoretical face pressure and drag characteristics of forward-facing steps in supersonic turbulent boundary layers

A theoretical investigation of the pressure distributions and drag characteristics was made for forward facing steps in turbulent flow at supersonic speeds. An approximate solution technique proposed by Uebelhack has been modified and extended to obtain a more consistent numerical procedure. A comparison of theoretical calculations with experimental data generally indicated good agreement over the experimentally available range of ratios of step height to boundary layer thickness from 7 to 0.05

Analysis of pressure distributions for a series of tip and trailing-edge controls on a 60 deg wing at Mach numbers of 1.61 and 2.01

Supersonic pressure distributions for tip and trailing edge controls on 60 deg delta win

Theoretical pressure distributions over arbitrarily shaped periodic waves in subsonic compressible flow and comparison with experiment

Theoretical solution for pressure distribution over arbitrarily shaped periodic waves using Fourier serie

Pressure drags due to two-dimensional fabrication-type surface roughness on an ogive cylinder at transonic speeds

Pressure drags due to two-dimensional fabrication- type surface roughness on ogive cylinder at transonic speed

Techniques for computing two-loop QCD corrections to b-->c transitions

We have recently presented the complete O(alpha_s^2) corrections to the semileptonic decay width of the b quark at maximal recoil. Here we discuss various technical aspects of that calculation and further applications of similar methods. In particular, we describe an expansion which facilitates the phase space integrations and the treatment of the mixed real-virtual corrections, for which Taylor expansion does not work and the so-called eikonal expansion must be employed. Several terms of the expansion are given for the O(alpha_s^2) QCD corrections to the differential semileptonic decay width of the b --quark at maximal recoil. We also demonstrate how the light quark loop corrections to the top quark decay rate can be obtained using the same methods. We briefly discuss the application of these techniques to the calculation of the O(alpha_s^2) correction to zero recoil sum rules for heavy flavor transitions.Comment: 22 pages, revte

Measurement by wake momentum surveys at Mach 1.61 and 2.01 of turbulent boundary-layer skin friction on five swept wings

Measurement by wake momentum surveys at Mach 1.61 and 2.01 of turbulent boundary layer skin friction on five swept wing