Powerplants Flashcards
(27 cards)
What is the definition and formula of “force”?
Force=Mass x Acceleration / F=M x A
Measured in units of newtons or pounds force.
What is the definition and formula of “work done”?
Work Done=Force x Distance / W=F x D
Measured in units of Joules or Foot pounds
What is the definition of ‘’Power” and what is the units used?
Work done per unit time.
Measured in joules/second (watts)
Or
Foot pounds per minute, expressed in horsepower (HP)
1HP=33,000 foot pounds/minute
What is Newton’s first law of motion (The Inertia Law)
A body will remain at rest or in uniform motion in a straight line unless acted on by an external force.
What is Newton’s second law of motion (The Momentum Law).
The acceleration of a body from a state of rest or uniform motion in a straight line, is PROPORTIONAL to the applied force and INVERSELY PROPORTIONAL to the mass of the body.
What is the acceleration formula?
Acceleration= Velocity(final) - Velocity(initial) / Time(t) in m/s
What is Newton’s third law of motion (The Reaction Law)
For every action there is an equal and opposite reaction.
What is the first law of thermodynamics?
Heat and mechanical energy are mutually convertible. The rate of exchange is constant and can be measured.
What is the second law of thermodynamics?
Heat cannot be transferred from a region at a lower temperature to one at a higher temperature without the expenditure of energy from an external source.
Bernoulli’s Theorem - What are the three forms of energy?
1) The energy due to it’s height or position (the potential energy).
2) The energy due to it’s pressure.
3) The energy due to it’s movement (the kinetic energy)
note: In the streamline flow of an ideal fluid the sum of all these is constant.
What is the definition of the ‘’Continuity Equation’’?
For a flow of air to remain streamlined, the mass flow passing a particular point in a set period of time must remain constant.
What is the formula for Bernoulli’s Continuity Equation (Constant Mass Flow)?
Mass = Area (A)
x Density (D)
x Velocity (V)
= a constant (K)What happens at the ‘’convergent duct’’ in a Venturi tube?
Velocity Increases
Pressure Decreases
Temperature Decrease
What happens at the “narrowest point (throat)’’ in a Venturi tube?
Maximum Velocity
Minimum Pressure
Minimum Temperature
What happens at the “divergent duct” in a Venturi tube?
Velocity decreases
Pressure increases
Temperature increases
How is a Venturi useful in a carburettor?
At the narrow section of the Venturi, fuel can be sucked into the throat of the carburettor as the pressure will have dropped, causing a vacuum effect.
What is the definition for Boyle’s Law?
If a fixed gas is held at temperature, the volume of that gas is inversely proportional to it’s absolute pressure.
What is the formula for Boyle’s Law?
Pressure (P) x Volume (V) = a constant (K)
What’s is the definition of ‘’Charles’s Law /Gay-Lussacs Law’’?
If a fixed mass of gas is held at a constant pressure, it’s volume is directly proportional to it’s absolute temperature.
What is the formula for Charles’s Law /Gay-Lussacs Law’’?
Volume (V) / Temperature (T) = constant (K)
What is the ‘’Combined Gas Law (Ideal gas Law)’’ ?
By combining Boyle’s Law and Charles’s law’s together we can get a combined gas law which represents the relationship between the volume, pressure and temperature of a fixed mass of gas.
What is the formula for the ‘’Combined Gas Law (Ideal gas Law)’’ ?
Pressure (P) x Volume (V) / Absolute Temperature (T) = a constant (K)
P1 x V1 / T1 = P2 x V2 / T2
Describe the induction stroke in a theoretical internal combustion engine.
The piston moves down, volume increases, pressure reduces, temperature falls.
Describe the compression stroke in a theoretical internal combustion engine.
The piston rises, volume reduces, pressure increases, temperature rises.
