You need to check out the new pipe sizing application called Pipe Sizer. This is a great new addition to our engineering calculators.
***NOTE: THIS APPLICATION HAS NOT BEEN TESTED ON THE iPod Touch — IT HAS ONLY BEEN TESTED ON THE iPhone 3GS***
Here is a quick and handy calculator that will determine the required pipe internal diameter for a given flow rate and velocity requirement. All you have to do is enter the flow rate, select the flow rate units and then select your low and high velocities. Note that the metric flow rate velocities are in m/s and the USCS is in ft/s.
You have a choice of the following units for the flow rate: ft^3/s, ft^3/min, ft^3/h, gal/min, gal/h, gal/dy, MM gal/dy (millions of gallons), L/h, L/min, L/s, m^3/h.
Please leave any feedback regarding this application in the comments. We will take this information into account for the future updates.