Investigation of Transonic Drag Computations in Aerodynamic ...

Investigation of Transonic Drag Computations in APAS
4.2 WAVDRAG
The program called WAVDRAG is also called NASA Langley Program 2500 –
Wave Drag by Area Rule. The program is written in Fortran 77 and was developed in
1983. The program uses the numerical method developed by R.V. Harris as described in
reference (9).
4.2.1 Program Description
Like the wave drag calculations in APAS, WAVDRAG’s calculations are based
on Whitcomb’s area rule computation of equivalent bodies. Comparison of WAVDRAG
zero-lift results with wave drag including lifting effects from APAS would help confirm
the accuracy of APAS by checking the magnitude and trend of it’s results. A comparison
would also possibly also provide evidence that the method used by APAS is actually
based on those of WAVDRAG.
Unlike APAS, there is no graphic user interface for WAVDRAG. The user must
follow a strict input file format in order to create a configuration that the program can
analyze. The program has been modified to run in the command-prompt environment of
Microsoft Windows. A screenshot of the program executing is shown in Figure 31.
Figure 31: WAVDRAG Command Screen
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