fully developed flow in the inlet of the helical pipe
 

hi everyone
i have an issue in making fully developed velocity profile (parabolic inlet velocity) in the inlet of my helical pipe. as you can see the pipe inlet Formulas in the below pictures, this Formulas totally works for me in the straight pipe, but it doesn't works at all in helical pipe and gives me the wrong answer.
i have set the maximum speed at 2.7 m/s as you can see but it shows me 663 m/s in the refrence value and in results. and also when i run the program, it almost shows me 100 percent reverse flow on the pressure outlet, so the flow inside the helical pipe is completely reversed (in results flow enters the helical pipe in the outlet and flows out in the inlet).
what can i do to fix this?
i appreciate your help.