I have an equation that has to do with weirs and flow rates, Q=288.8LH^(3/2) where Q is the discharge rate (gal/hr), L is the opening lenth (inches), and H is the height of the fluid (inches). How do I find a new constant if I where to change Q to (cubic feet/sec.) and L and H to feet? Thank you for your time.

Q gallon/hour = 288.8 * (L inches) * ((H inches)^1.5)

1 gallon = .13368 cubic feet (see www.nettam.com/convert.html)
1 hour = 3600 seconds
1 foot = 12 inches

Q * .13368 cubic feet/3600 seconds = 288.8 * ((L/12) feet) * ((H/12) feet)^1.5

Q = (3600/.13368) * (288.8/12) * ((1/12)^1.5) * L * (H^1.5)

Q = 15591.22 * L * (H^1.5)