Showing papers by "Earl H. Dowell published in 1985"

Reply by Authors to K. L. Roger

Abstract: Second, the most desirable relative location of the doublet/averaging area is that which yields lifting line results when used subsonically with one patch per chord. When averaging over a parallelogram patch, the preferred doublet location is \/(e + 1) = 1 1 .92% of patch chord at the spanwise patch center, whereas Ref. 1 used the leading edge. This is discussed in Ref. 2 for the analogous downwash-point method. [Reference 2 also used unsteady/steady kernal ratios for supersonic solutions, as in Eqs. (19a) and (19b) of Ref. 1, but did not recognize the extra term in Eq. (19c), Ref. 1.] Figure 2 illustrates the use of this doublet location and of Eq. (1) with N=5, using the planforms of Ref. 3. Patch centers of pressure are not dictated by the doublet location used in forming the influence matrix, but may be assumed to be at 25% chord for M< 1, at 50% chord for supersonic patch leading edges, and interpolated for in-between Mach numbers.