pricer

05-30-2004, 11:04 AM

When changing cubic feet per minute to cubic meters per minute what is the best way to make the conversion? I use a vane anemometer set to read feet per minute when measuring large grilles and openings. The next information that will need to be known is the true area (aK factor) for grilles and vena contracta for the air passages that have no grilles.

I would then measure the grille in many locations, every square foot of the grilles surface and find the average feet per minute. Then I would measure the grille and find the square inches of the face and multiply this sum by the manufacters free area correction factor. Once this is figured I would find the grilles are in square foot by dividing it by 144 square inches.

Next I would multiply the average velocity by the area in square foot to find the cubic feet per minute. Now to convert cfm into cubic meters per minute I would multiply the cfm's by 1.699. This will give me cubic meters per hour.

We run into this while balancing air flow in marine aplications on drill rigs and ships here and around the world. If anyone would like to share information like this I am sure that it would be appreciated by all or if anyone has a more accurate way to achive the results that would be appreciated as well.

Thanks,

I would then measure the grille in many locations, every square foot of the grilles surface and find the average feet per minute. Then I would measure the grille and find the square inches of the face and multiply this sum by the manufacters free area correction factor. Once this is figured I would find the grilles are in square foot by dividing it by 144 square inches.

Next I would multiply the average velocity by the area in square foot to find the cubic feet per minute. Now to convert cfm into cubic meters per minute I would multiply the cfm's by 1.699. This will give me cubic meters per hour.

We run into this while balancing air flow in marine aplications on drill rigs and ships here and around the world. If anyone would like to share information like this I am sure that it would be appreciated by all or if anyone has a more accurate way to achive the results that would be appreciated as well.

Thanks,