Expert: Paul Soderman - 3/31/2008

Question
what are the calculations used in solid blockage,wake blockage,tare and interference corrections,stream line curvature?

Answer
Jai
Books have been written on this subject, which is much too broad for me to answer in detail.  I refer you to the book:

Pope A and Rae WH. Low-Speed Wind Tunnel Testing, John Wiley, New York, 1984.

Wind tunnel walls produce numerous effects on wind tunnel models that are not found in flight.  Rae and Pope list nine effects in the beginning of chapter 6.  The so-called solid blockage causes an increase in dynamic pressure, which affects all the aerodynamic forces.  In addition, wake blockage primarily affects drag and requires a special correction to drag.  Other factors alter the model angle of attack, which primarily affects lift.  So, to answer your question, engineers calculate different corrections for lift, drag, and moments except for the dynamic pressure correction which affects all forces equally.  The calculations are summarized in the book.

You can also find information by googling wind tunnel corrections.
Paul