Lesson 1: Fundamental Properties of Fluid Flashcards
___________________ is the science that deals with the action of forces on fluids at rest, as well as in motion.
Fluid mechanics
the study of fluids at rest
Fluid statics
the study of fluids in motion
Fluid kinematics
the study of the effect of forces on fluid motion.
Fluid dynamics
It is a branch of science concerned with the practical applications of fluids, primarily liquids, in motion.
Hydraulics
_________ exists in two states – the solid state and the fluid state.
Matter
Because molecules in solid state are spaced very closely, solids possess __________________ and __________ of form
compactness, rigidity
fluids do not possess any ___________ of form.
rigidity
____________ exists in two forms: liquid and gas.
Fluid
A liquid has a free surface and gas does not.
True or false?
True
Liquids are practically incompressible while gases are compressible.
True or false?
True
The mass per unit of volume.
Density
The weight per unit of volume of a fluid.
Unit weight
The volume occupied by a unit mass of fluid.
Specific volume
The ratio of specific weight of a given liquid to the specific weight of water at a standard reference temperature (4°C)
Specific gravity
The amount of resistance of a fluid to shearing forces. It describes the internal friction of a moving fluid.
Absolute or Dynamic Viscosity
The ratio of dynamic viscosity of the fluid, μ, to its mass density, ρ.
Kinematic Viscosity
Variation of Viscosity with Temperature
Liquids – ___________________
where Viscosity decreases as temperature increases.
cohesion and momentum transfer
Variation of Viscosity with Temperature
Gases – _______________________________________ where Viscosity increases as temperature increases.
molecular momentum transfer
bonding of dissimilar molecules
adhesion
bonding of similar molecules
cohesion
A contractive tendency of the surface of a fluid that allows it to resist an external force.
Surface tension
The movement of a liquid through a thin-bore tube
Capillarity
the force exerted by the vapor.
vapor pressure
The vapor should meet the following conditions in order to exert the vapor pressure:
The vapor should be in _____________ with its liquid or solid phase.
Vapor should be at a _____________ temperature.
Both vapor and its condensed form should exist in a _____________ system.
equilibrium, constant, closed
A fluid that is both incompressible and have no viscosity. Its bulk modulus is infinite. It has no surface tension.
Ideal fluid
A fluid that possesses viscosity, finite compressibility and surface tension.
Real fluid
A fluid in which the shear stress is directly proportional to the shear strain or velocity gradient
Newtonian fluid
A real fluid that doesn’t follow the Newton’s law of viscosity.
Non-Newtonian fluid
The viscosity of these fluids decreases as the stress increases
Pseudoplastic fluid
A fluid which viscosity increases as stress is applied
Dilatant fluid
It does not flow until a critical stress (yield stress) is exceeded and then flows at a rate proportional to the excess of stress over the yield stress
Bingham plastic
There is a decrease in viscosity with time under a constant applied shear stress.
Thixotropic fluid
Fluid that has an increase in their viscosity as the time of application of stress increases
Rheopectic fluid
Water
Newtonian
Air
Newtonian
Oobleck
NN, dilatant
Toothpaste
NN, Bingham
Ketchup
NN, Pseudoplastic
Egg white
NN, Rheopectic
Nail polish
NN, Thixotropic
Mayonnaise
NN, Bingham
Quick sand
NN, Pseudoplastic
Honey
Newtonian
