New Wind Tunnel (Cincinnati)

[metcalfmj]

We just built a custom wind tunnel in Cincinnati. I wanted to take a minute to introduce myself and our company. My name is Mike Metcalf and I represent Engineering & Scientific Innovations, Inc. We are located in Cincinnati, OH right off I-75.
Recently, we have finished the construction of a Wind Tunnel facility that I think will really be of interest within several different communities. We plan to focus on Green Energy solutions, UAV/Small aircraft components, helmet designs, and Cycling/Sports sciences. We also have diverse research backgrounds in other areas, one being High-Speed Imaging. We can offer affordable, expert wind tunnel test services, and have the necessary tools on hand, that allow us to meet many different needs at one location.

We are a small woman-owned engineering firm, associated with Wright-Patterson Air Force Base and other DoD agencies. We serve both commercial and military clients.



Please feel free to contact me.

Mike Metcalf
Project Specialist
Engineering & Scientific Innovations
4976 Provident Drive
Cincinnati, Ohio 45246
(Office) (513) 605-3700

[NeilBlanchard]

How large is your tunnel? I have a 1/4 scale model of my CarBEN EV design that I would love to test. It is about 1.5 sq ft frontal area, and is about 42" long. Would the full size CarBEN EV fit -- it is about 25.1 sq ft and about 14' long.

[metcalfmj]

The scale model would be easy. Right now I can fully "wet" a 3ft x 3ft (frontal) cross section. In the open jet area (length) I have 7ft. Immediate plans are to expand the tunnel to accept larger items, such as a cyclist on a bike. I have to gain the commercial interest to validate the upgrades.

[botsapper]

The aftermarket/car tuners' must-have tool, along with the engine & chassis dynamometers, is some wind tunnel facility lab time.

[mnmarcus]

Originally Posted by NeilBlanchard

How large is your tunnel? I have a 1/4 scale model of my CarBEN EV design that I would love to test. It is about 1.5 sq ft frontal area, and is about 42" long. Would the full size CarBEN EV fit -- it is about 25.1 sq ft and about 14' long.

Wonder what the difference in drag calculations would be for a 1:4 scale... Couldn't be 1 to 1 right?

[NeilBlanchard]

I believe if the air velocity is 4X as high, then the drag does scale.

[KamperBob]

Originally Posted by NeilBlanchard

I believe if the air velocity is 4X as high, then the drag does scale.

My brain struggles with this. I've read about Reynold's scaling. Here's my puzzle. Drag force is directly proportional to area and the square of velocity.

A 1/4-th scale model should have 1/16-th the area of full scale. Speed is supposed to be 4X for the scale model. That term squares to 16X which cancels the 1/16-th area term. The resulting "force" looks the same for both the full and small scale vehicles. But since the area is reduced doesn't that mean pressures would be 16X on the 1/4-th scale model by comparison?

This does not seem to compute. What am I missing?

[NeilBlanchard]

I may well be wrong -- I know that some compensation can be done physically and/or mathematically. Some labs use water or some oil to increase the drag on a scale model to get the right results.

[smck]

Nice you're only 10 minutes from where I work. Too bad it won't fit my Golf. Welcome to ecomodder neighbor.

[Bill in Houston]

Some tunnels operate at higher pressures, too. Like multiple atmospheres of pressure.