Simscape fluids pipe elevation gain

hi, just looking for a bit of contextual help with simscape fluids and the pipe block.

mainly the elevation gain parameter:

am i right in my assumptions that the elevation gain from port A to B is in laymans terms "how high vertically is port B from port A"?

if so, how does it factor in a ramping height? because that would affect flow (ramp vs straight up)?

i'm trying to model a cooling system that has some vertical pipes from a manifold and i thought that was how it worked, effectively the physical head distance from inlet to outlet, so if it was going doing and inlet was A, it would be -x (m) from A to B?

i hope my odd question makes sense? the info page was confusing me because it was a bit vague on this particular parameter...

[Torsten]

If A is at height 6 m and B is at height 7 m (measured from some fixed reference height) and the elevation gain specification is constant, then the elevation gain from A to B is 1 m.

If A is at height 7 m and B is at height 6 m (measured from some fixed reference height) and the elevation gain specification is constant, then the elevation gain from A to B is -1 m.

Does this anwer your questions ?

Answer 1

[Yifeng Tang]

Hi @Seth,

Yes, that term is indeed ""how high vertically is port B from port A". Mathematically, it's a rho*g*h term added to the pressure at A, meaning A end is lower. If you have multiple segments in this pipe, the rho*g*h term is divided accordingly.

ramp vs straight up: well, it's just a rho*g*h term. So there is no difference I assume. One crazy thing I found is that the block allows the elevation change to be greater than the pipe length.

In short, if B is at a higher point than A, the elevation is positive.

One thing to pay attention to: if your liquid network forms a closed circuit, make sure the total elevation around the loop sums to zero. Otherwise you'll have an infinitely supply of gravitational energy (which would be GREAT!). Also, check out this documentation page if you close your cooling loop.

[Seth]

hi Yifeng, thanks for the confirmation!! that is certainly an interesting point about the summing to 0, it does raise an interesting question though, my cooling network is modelled after a physical existing network and i wonder if those differences in height actually do sum to 0...