Airflow Acceleration, Deceleration, and Fan Placement

That's the function of the contraction, which is the blue portion. It starts off with a 4:1 contraction and smoothly accelerates the air flow to get it up to about, in our case, 130 mph. And then as it goes through the test section and it empties out in the diffuser, that diffuser is slowing down the air in a very uniform manner. So it's not about quality of the air flow, but it's about recovering all that energy that you've put into the air because we've got 2400 horsepower that we're putting into that air. And we would like to recover as much of that as possible. If we don't, we would have to have 5 or 6,000 horsepower to do the same job. The other thing is you don't see any fans in the front. The fans are all at the rear for a very simple reason. Air coming off the fans is really a turbulent mess. You don't want a turbulent mess coming into the test section for this car. You want the air to be very smooth and very uniform. So, if you put the fans in the back, you're sucking the air through the honeycomb and then it is very smooth and very well defined when it hits the car. And that's how you can measure it with that precision. The turbulence doesn't really do you a lot of good when you're in the testing phase. Yes, there is turbulence out on the racetrack and that's unavoidable, but the turbulence is a big variable. We don't want large scale turbulence because you never get the same answer twice. This kind of works like a carburetor. Was that the venturi effect? How it in a sense? Although it's interesting you say that. Yes, you could kind of describe it as a ventury, but it's ex it's exactly the opposite reason that we have a ventury in a carburetor. A ventury is designed to generate a low pressure to suck the fuel up into the carburetor. We're not about uh generating low pressures, but we are about generating high velocities. Now, the two are related. As the velocity goes up, the pressure goes down, but we really aren't designing it to get a low pressure. We're designing it to get a very high speed. So it's kind of opposite ends of of getting the same effect. But yes, it is a contraction, a small section, and then an expansion. So in that regard, it is similar to a venturi, just not the same function. So that stuff is interesting to me. Like all the we're going to get in all the like boundary layers and you know those kinds of things. That's kind of stuff that I want to learn about and how you measure it, I guess. Sure. Well, we could start off. We…