CAN I INCREASE THE FLOW/PRESSURE IN A 1 METER DIA. PIPE BY ADDING A LARGE COWLING

I HAVE A ONE METER IN DIAMETER PIPE IN A WATER COLUMN..
FOR THE PURPOSE OF COLLECTING THE FLOW TO TURN A WATERWHEEL

I WANT TO KNOW IF BY ADDING

A TWO METER IN DIAMETER COWLING TO THIS PIPE
CAN I ADD TO THE FLOW OR PRODUCTION OF THE PIPE...
I REALIZE THAT WATER DOESNT COMPRESS

SO THE QUESTION REMAINS WILL A GREATER/LARGER INTAKE CAUSE GREATER PRESSURE
OR WILL THE WATER SIMPLY GO AROUND THE COWLING TO THE LOWER PRESSURE AREAS IN THE WATER COLUMN..

IF IT IS POSSIBLE TO INCREASE THE PRESSURE/FLOW IN THE PIPE IS THERE A FORMULA TO CALCULATE THE EXPECTED INCREASE

MY GUESS IS THAT A INCREASE IN THE INTAKE AREA OF 100 % WILL INCREASE THE PRESSURE THRU THE PIPE BY 25 %... THE OTHER 75% WILL BE LOST TO RESISTENCE IN THE PIPE...

THANK YOU FOR YOUR TIME AND CONSIDERATION THE WATERHORSE