How long should be domain for external flow
 

Hi friends,

I want to simulate flow around a missile (subsonic flow). some references say the domain around the missile should be 10-15 times length of missile. But I found an article that it's domain was 60 times diameter of missile.
Which one is correct? (10*L Or 60*D )??

I appreciate your help
thanks and best regards,
Sasan.

You should go for 15* Length for upstream and sides and 25* length for downstream