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Peter Kämpf
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Wind tunnels are stingy with the data they reveal. They only give the total value but not neatly split into its contributions. Therefore, any such table needs to be calculated.

Since XFOIL, which is now around for more that 30 years, we have such a tool and it does output the single contributions. However, I know of no publicly available collection which lists those drag components for a range of airfoils. And since XFOIL becomes unreliable with larger flow separation, the data is only valid for attached flow and maybe a bit beyond. But certainly not up to 30°.

In Xfoil, load an airfoil and enter OPER. Compute the desired point and switch into VPLO. There you can plot the skin friction coefficient with the CF command. In order to extract its numerical value, toggle the PACC switch in OPER and save a range of points to file. In the file you will find to the right of the CD column one labeled CDp. This is the pressure part of the drag. Use a tabulation software of your choice to calculate the difference between CD and CDp: This should be the friction part of the drag coefficient.

Wind tunnels are stingy with the data they reveal. They only give the total value but not neatly split into its contributions. Therefore, any such table needs to be calculated.

Since XFOIL, which is now around for more that 30 years, we have such a tool and it does output the single contributions. However, I know of no publicly available collection which lists those drag components for a range of airfoils. And since XFOIL becomes unreliable with larger flow separation, the data is only valid for attached flow and maybe a bit beyond. But certainly not up to 30°.

Wind tunnels are stingy with the data they reveal. They only give the total value but not neatly split into its contributions. Therefore, any such table needs to be calculated.

Since XFOIL, which is now around for more that 30 years, we have such a tool and it does output the single contributions. However, I know of no publicly available collection which lists those drag components for a range of airfoils. And since XFOIL becomes unreliable with larger flow separation, the data is only valid for attached flow and maybe a bit beyond. But certainly not up to 30°.

In Xfoil, load an airfoil and enter OPER. Compute the desired point and switch into VPLO. There you can plot the skin friction coefficient with the CF command. In order to extract its numerical value, toggle the PACC switch in OPER and save a range of points to file. In the file you will find to the right of the CD column one labeled CDp. This is the pressure part of the drag. Use a tabulation software of your choice to calculate the difference between CD and CDp: This should be the friction part of the drag coefficient.

Source Link
Peter Kämpf
  • 237.3k
  • 17
  • 601
  • 944

Wind tunnels are stingy with the data they reveal. They only give the total value but not neatly split into its contributions. Therefore, any such table needs to be calculated.

Since XFOIL, which is now around for more that 30 years, we have such a tool and it does output the single contributions. However, I know of no publicly available collection which lists those drag components for a range of airfoils. And since XFOIL becomes unreliable with larger flow separation, the data is only valid for attached flow and maybe a bit beyond. But certainly not up to 30°.