ME 116
Fluid Mechanics
TEST 1: Fluid Properties, Pressure Measurement, Hydrostatic Forces, Rigid Body Motion, Newton's 2nd Law, Bernoulli's Equation
TEST 2: Velocity and Acceleration Fields, Reynold's Transport Theorem, Finite Control Volume Analysis, Dimensional Analysis and Similitude
TEST 3: Internal Flow, External Flow, Boundary Layer Theory, Drag and Lift
Test 1 Concepts and Materials
Fluid Properties and Pressure Measurement
Important Concepts:
Units used when measurement units and their meaning (Imperial v. Metric)
The difference between absolute and gauge pressure
The concept of fluid shear
Vapor Pressure, Compressibility, and the Speed of Sound in a fluid.
Fluid shear is the nature by which fluid flows along a wall or boundary. One of the most important rules and concepts in fluid dynamics is the "Zero Boundary Condition." This assumption states that due to friction forces along a wall, average velocity along the wall is ZERO. As distance from the wall increases, velocity increases.
In a gas of mixed composition, such as normal air, the total pressure can be described as the sum of component vapor pressures.
Example: The absolute pressure in a canister is 10 psi, and it consists of helium and hydrogen gas. The hydrogen gas has a partial pressure of 7 psi. What is the partial pressure of the helium?
Answer: Subtract the known partial pressure from the total pressure to find the unknown. The partial pressure of the helium is 3 psi.
Hydrostatic Forces
Hydrostatic forces involve the change in pressure caused by gravity in a fluid. This pressure is linearly related to depth in the fluid by the following equation
Pressure = density * gravity constant * depth
For example, a person can swim underwater in a pool, but it would take a very advanced submarine to journey to the bottom of the ocean. This is due to hydrostatic pressure increasing as depth increases.
