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eport typos and errors to W.H. Mason Appendix D: Programs D-475. DELTA CP AT DESIRED CL - ∆C p or Net C p normal to the surface at dihedral foreach elemental panel when the total lift is C L , d. This is located across the panel as anaverage. It corresponds to the incremental lift associated with the bound vortex strengthof the particular panel:The fourth group of data presents the following geometric results:1. REF.CHORD - Reference chord of the configuration.2. C AVERAGE - Average chord, cav, true configuration area divided by true span.3. TRUE AREA - True area computed from the configuration listed in second group ofgeometry data.4. REFERENCE AREA - User input reference area.5. B/2 - Maximum semispan of all planforms listed in second group of geometry data.6. REF. AR - Reference aspect ratio computed from the reference planform area and truespan.7. TRUE AR - True aspect ratio computed from the true planform area and true span.8. MACH NUMBER - Mach number.AERODYNAMIC DATA∆C p × ∆c = ∆L i , where ∆L i = ρU ∞ Γ iIf PTEST = 1. or QTEST = 1. on the configuration card, then either C lp or C L q and C mq arecomputed and printed, followed by program termination. Otherwise, the aerodynamic data aredescribed by at least two groups of results. The first is always present, but the second dependson what is requested on the configuration card. The following items of the first group of data aregiven in the order that they are found on the printout. Note that CL ALPHA, CL(TWIST),CM/CL, CMO, CDI/CL**2 are based on the specified reference dimensions. Many of the itemsthat follow are for the complete configuration.1. DESIRED CL - Desired lift coefficient, CL, d, specified in Input Data forcomplete configuration.2. COMPUTED ALPHA - Angle of attack at which the desired lift is developed:CL, d/(CL ALPHA) + ALPHA at CL=O.3. CL(WB) - That portion of desired lift coefficient developed by the planform withthe maximum span when multiple planforms are specified. When one planform isspecified, this is the desired lift coefficient. (If two planforms have the samespan, and this value is equal to the maximum, the planform used here is the latterone read in).4. CDI AT CL(WB) - Induced drag coefficient for lift coefficient in the previousitem. When two or more planforms are specified, this is the induced dragcoefficient of only the planform with the maximum span. This result is based onthe far-field solution.5. CDI/(CL(WB)**2) - Induced drag parameter computed from the two previousitems.Friday, November 17, 1995
D-48 Applied Computational Aerodynamics6. 1/(PI*AR REF) - Induced drag parameter for an elliptic load distribution based onreference aspect ratio.7. CL ALPHA - Lift-curve slope per radian, and per degree.8. CL(TWIST) - Lift coefficient due to twist and/or camber at zero angle of attack(CL,tc).9. ALPHA AT CL=O - Angle of attack at zero lift in degrees; nonzero only whentwist and/or camber is specified.10. Y CP - Spanwise distance in fraction of semispan from root chord to center ofpressure on the left wing panel.11. CM/CL - Longitudinal stability parameter based on a moment center about thereference point. This is the negative of the static margin:CM / CL Lamar = ∂C m∂C L⎛and the value of can be found from C mα = ∂C m⎞ ⎛⎜ ⎟ ⎜∂C L ⎞C mα⎟⎝ ∂C .L ⎠ ⎝ ∂α ⎠12. CMO - Pitching-moment coefficient at CL=O.For each spanwise station, the following data are presented; from the left tip towards theroot:1. 2Y/B - Location of midpoint of each spanwise station in fraction of wingsemispan.The next two columns of data describe the additional (or angle of attack) wing loading at a liftcoefficient of 1. (based on the total lift achieved and the true configuration area). The thirdcolumn is the chord ratio result, and the other columns detail specific kinds of span loadings andlocal centers of pressure for the configuration.2. SL COEF - span-load coefficient, c l c/C L c av .3. CL RATIO - Ratio of local lift to total lift, c l /C L .4. C RATIO - Ratio of local chord to average chord, c/c av .5. LOAD DUE TO TWIST - Distribution of span-load coefficient due to twist andcamber at 0° angle of attack for the configuration.6. ADD. LOAD AT CL= - Distribution of additional span-load coefficient requiredto produce zero lift when combined with lift due to twist and camber.This distribution is computed at C L , tc .7. BASIC LOAD AT CL=0 - Basic span-load-coefficient distribution at zero liftcoefficient. These data are the difference of the previous two columns of data.8. SPAN LOAD AT DESIRED CL - Distribution of the combination of the basicspan-load and additional span-load coefficients at the desired C L .9. AT CL DES - X LOCATION OF LOCAL CENT PR - The X location of thelocal center of pressure for the resulting span load at C L , das a function of 2Y/b.Friday, November 17, 1995
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