Tool/software:
I know that using USS design center GUI I can find the Meter constant.
But I want it theoretically. According to TI reference document it says meter constant = (Length * Area)/2
Also TI says Area = Pi*r*r. Which means area of circle. Why TI says in its calculation that Area = Pi*r*r. where r is radius of Flow tube.
It should be Area of cylinder as Flow tube is cylindrical. 
