403 - Chapter 2 Flashcards
Parallel Flow Path
Pressure only builds in the path of least resistance.
Series Flow Path
Pressure builds at each valve and adds up to a total.
Orifice
Narrowing of pipe or tube.
A pressure drop is created after the orifice.
If pressure is reduced then,
Rate of flow is also reduced.
Doubling diameter:
Halving diameter:
Quadruples area.
Quadruples velocity.
Designing a hydraulic system:
- Stroke length
- Load
- Area
- PSI
The sum of pressure and kinetic energy is constant with a constant flow rate
True
SUS
Saybolt Universal Seconds
Greater the Viscosity Index =
Less change in viscosity due to temperature.
High viscosity:
Thick high resistance to flow.
Increased power consumption due to friction.
Increased pressure drops through valves and lines.
High temp due to increased friction.
Low viscosity:
Increased leaking
Excessive wear
Two types of fluids:
Newtonian
Non-Newtonian
Newtonian fluids
Viscosity is constant and independent to the rate of shear.
Ex: water, most mineral oils, gasoline, kerosine
Non-Newtonian fluids
Viscosity is not constant and not independent of the rate of shear.
Ex: clay, mud, ketchup, tar…most are natural things.
Continuity Equation:
For steady flow in a pipeline the flow rate is e same for all cross sections of a pipe.
