Yes, they were with emulsion shocks. The air is a big unknown, but it's not completely impossible to account for. The question is how much air. An air/oil mixture is simply two springs in series. The lighter spring squishes easier than the stiffer spring, so the sum of the two will always be less than the lighter one. The spring property of air and oil is bulk modulus. If you know each of them, you can calculate the spring effect. Oil IS compressible, it's just very small displacement or volume change. Air is highly compressible, so it dominates. If you know the % Air in the oil, you can calculate it with this formula (Effective spring rate, Keff = 1/(1/Koil)+%air*(1/Kair)) K = bulk modulus. Air is simply the pressure of the air or 101kPa at atmospheric pressure. Oil is approximately 850,000kPa for 300 cSt silicone oil at 25C. The difficult part is the %air.

I'm not sure how the air affects the viscosity and flow effects though, that's something we'll be working on. I did show air influence in the presentation, but it doesn't seem convincing enough for me, (even though I repeated the test a few times getting the same results each time). I need to come up with a better, more convincing way. Otherwise, if the data holds up, the air doesn't influence the damping coefficient much, only the hysteresis.

As for your calculations, you should be on the right path, as long as you have the right damping coefficient, or at least understanding how it changes depending on your damper configuration (piston, viscosity, etc)