MRS957
Mechanical
- Jun 25, 2002
- 6
I need to determine the total drag force applied from a moving liquid to an elliptical shaped pipe. The final objective is to determine the bending moment and the bending stress of the pipe due to this force. Drag loads are outside my normal job requirements, therefore I have very little information on drag coefficients.
To visualize the problem, imagine a flowing river with a partially submersed 10 foot long vertical post. The top end of the post is bolted to a boat dock 2 foot above the waters surface, the bottom end of the post is not attached to anything and is approx. 2 foot above the bottom of the river bed. The water velocity is in the range of 2 to 25 foot/sec.
The elliptical pipe is essentially a 10 foot long, 4.5 inch od round steel pipe which has been somewhat flattened into an elliptical cross section.
The ellipse outside dimensions are approx. 5.5 inch major axis x 3.3125 inch minor axis (ratio of 1.66:1)
The flow direction is perpendicular to the long axis of the ellipse.
I have found several references which state the drag force coefficient Fd as 1.6 but have not found anything on the lift coefficient.
Thanks in advance
To visualize the problem, imagine a flowing river with a partially submersed 10 foot long vertical post. The top end of the post is bolted to a boat dock 2 foot above the waters surface, the bottom end of the post is not attached to anything and is approx. 2 foot above the bottom of the river bed. The water velocity is in the range of 2 to 25 foot/sec.
The elliptical pipe is essentially a 10 foot long, 4.5 inch od round steel pipe which has been somewhat flattened into an elliptical cross section.
The ellipse outside dimensions are approx. 5.5 inch major axis x 3.3125 inch minor axis (ratio of 1.66:1)
The flow direction is perpendicular to the long axis of the ellipse.
I have found several references which state the drag force coefficient Fd as 1.6 but have not found anything on the lift coefficient.
Thanks in advance
