Hydraulic tubes

Hydraulic tubes are presented as multi-pole models with four poles ( four pole models). Four different tube models are in use (denoted by suffixes G, H, Y and Z) depending on input and output poles. Two two-pole models are in use for dead-end tubes of type g and h.

Ports:

• Q1 - Volumetric flow at the left end of the tube
• Q2 - Volumetric flow at the right end of the tube
• p1 (p1e) - pressure at the left end of the tube
• p2 (p2e) - pressure at the right end of the tube

Properties for tubes are as follows:

• l – length of tube, m
• d – inner diameter of tube, m
• K – bulk modulus of the tube material, bar
• s - thickness of tube wall, m
• nc - number of similar connected tubes
• kr - coefficient of correcting the stationary resistance of tube for dynamics
• epsap - allowed absolute error
• epsr - allowed relative error
• initQ1 - initial approximate value of Q1, m3/s
• initQ2 - initial approximate value of Q2, m3/s
• initp1 -initial approximate value of p1, Pa
• initp2 -initial approximate value of p2, Pa