Drag coefficient for Finite circular cylinder of low aspect ratio

[vader]

HI
i have been involved with a problem which requires me to calculate the drag of a finite circular cylinder of very low aspect ratio (~1.2) i.e the h/d= 1.2
The Re_d= 5.4x 10⁵ (based on diameter)
and the Re_x = 8.46x 10⁶
The flow regime is very low subsonic ( M=0.15)
I need to predict the drag contribution of this body on an a/c
I have gone through various ESDU( 83025 and 80025) and an AGARDDoc Aircraft Excrescence Drag by A D Young, but to no help as these do not contain the flow regime i am aiming at.
I would like help with respect to above problem regarding that someone could point me out in the right direction as to where to look or whether i need to look only for 2D cases here as the aspect ratio is so low.

 

[Navin A S]

One approach you could take to calculate the drag of a finite circular cylinder with a very low aspect ratio is to use the 2D drag equation. The drag equation for a 2D cylinder is given by: D = 0.5ρV2A + cD(1-2/π)(AR/2) where ρ is the air density, V is the flow velocity, A is the cross-sectional area of the cylinder, cD is the coefficient of drag, and AR is the aspect ratio of the cylinder (h/d). You can then calculate the drag for your particular case using the Red and Rex values you have calculated. Additionally, you may want to consider using computational fluid dynamics (CFD) to more accurately model the flow around your cylinder. This can help you to better understand the flow regime and the effect it has on the drag.