#### Longitudinal Aircraft Dynamics #2 – 2D polynomial interpolation of parameters cl, cd and cm

05/24/2011

In the previous section, the main wing airfoil and the horizontal stabilizer airfoil were simulated using Xflr5. The three coefficients, lift, drag and moment were then interpolated on charts in Excel using 4th and 5th order polynomials. This section shows a few tricks about how to easily introduce those 60 equations as spreadsheet formulas in Excel ranges. It also presents a simple linear interpolation method across the Reynolds number range. We need to do this since we simulated…

#### Longitudinal Aircraft Dynamics #1 – using Xflr5 to model the main wing, the horizontal stabilizer and extracting the polynomial trendlines for cl, cd and cm

05/23/2011

This is a tutorial about using a free aerodynamic modeling package (Xflr5) to simulate two airfoils in 2D (the main wing and the horizontal stabilizer) for ten different Reynolds numbers, then using Excel to extract the approximate polynomial equations of those curves (cl, cd and cm) and based on them, simulate a 2D aircraft as an animated model. This section deals with the aero modeling and the 4th and 5th order polynomial extraction….

#### Aerodynamics Naive #3 – a brief introduction to Xflr5, a virtual wind tunnel

05/19/2011

The previous section implemented and charted the ping-pong polar diagrams in a spreadsheet and showed a reasonble similarity, for moderate angles of attack, between these diagrams and the ones modeled using Xflr5, a virtual wind tunner. This section introduce the  concept Reynolds number and it also contains a very brief introduction to Xflr5, the free virtual wind tunnel software.

#### Aerodynamics Naive #2 – spreadsheet implementation of the Ping-Pong polar diagrams

05/18/2011

This section of the tutorial implements the lift and drag formulas in a worksheet, creating and charting the polar diagrams for an ultra simplified ping-pong model of an airfoil. Comparing these diagrams with ones obtained by using a virtual wind tunnel (XFLR5) we can see a decent resemblance for moderate angles of attack (smaller than about 8 degrees in absolute value). [sociallocker][/sociallocker]