Would Sref be sum of areas of both, the front and the back wing? or just one wing? Assuming both the wings have equal areas (image below)
Details - So, I am calculating drag using the component drag build up method and using the below equation for the following parts of my box wing design.
- Front Wing
- Aft Wing
as you can see in the equation below, Swet for all different parts are divided by "Sref". For example assuming that both wings have area of 10m^2 and therefore wetted area of roughly about 20m^2 each.
for Cd0 calculation what should use as my Sref? total lift generating area of the aircraft, as in 10+10=20? or just the area of any one wing, 10?
If I use 20, for example, and apply the below formula for the front wing, my (Swet/Sref = 1) whereas it's = 2 if I use, Sref as 10m^2?
Basically, my total CD0 values changes drastically as I change my Sref according to the below equation, why is that?