What is the difference between a ‘bend’ and ‘elbow’?

What is the difference between a ‘bend’ and ‘elbow’ for the Local Resistance block? The only difference I found was that bend seems to allow for compressibility.

Answer 1

[MathWorks Support Team]

The difference between Elbow and Pipe bend include the following:

1) Compressibility effects are allowed in the bend.

2) In both blocks the pressure loss coefficient includes correction factors for the base friction and the bend angle.

3) The pipe bend also has a correction factor for the bend curvature (the ratio of the bend radius to the pipe diameter) in its pressure loss coefficient calculations. The elbow, however, does have the bend curvature correction factor in its pressure loss coefficient formulations. The bend curvature in the pipe bend block is always assumed to be smooth while the elbow can either represent smoothly curved, 90-degree or sharp-edged (Miter) bends.