For my senior design project, I have to reduce the aerodynamic drag of a truck and trailer. I am doing CFD simulations and wind tunnel testing. The dimensions of the wind tunnel (test section) are 94 in long, 13.5 in tall and 20 in wide and a cross-sectional area of 270 in^2 and it could go up to 110 mph. The truck and trailer has a total length of 712 in and a frontal area of 10560.2175 in^2. I'm trying to figure out a way to match the Reynolds Number of the full truck and trailer using a scale down model but have a blockage ratio of less than 5%. The Reynolds Number of the full scale is 34,695,627.05 at a velocity of 65mph and 712 inches for characteristic length. A scale of 1:17 gives me a blockage ratio of about 5% but a Reynolds number of 3,137,150 at 100mph and 41.88 in long, which is nowhere close to the actual Reynolds Number. What do you guys recommend I do about the wind tunnel testing if I can't match the Reynolds Number to the real one? P.S, I need the velocity to be 65mph because at that speed, most of the fuel is used to overcome drag. Sorry for the lengthy paragraph but I'm stuck.