Engine size and measurements
What is a typical pressure in psi in an engine?
125-175 psi
Force
A push or pull exerted on an object
Prony brake
A simple dynamometer that uses friction.
mechanical efficiency
All of the ways friction is lost in an engine.
oversquare engine
An engine that has a larger bore diameter than the length of its stroke.
undersquare engine
An engine that has smaller bore diameter than the length of the stroke.
BTU
British Thermal Unit
What determines engine size?
By multiplying the amount the cylinder displacement by the amount of cylinders.
work
Force exerted on an object that causes it to move
Road horsepower
Horse power avaliable at the vehicle´s drive wheels.
Chassis dynamometer
Measures the horsepower delivered to the drive wheels. As well as the fuel consuption, emissions, or noises.
How is force measured?
Newtons
gross horsepower
Power avaliable when only the water pump and the alternator are using power.
Energy
The ability to produce motion against an opposing.
compression pressure
The amount of pressure made by the pistons moving up and down.
indicated horsepower
The amount of pressure mde in the combustion chamber.
bore
The diameter of the cylinder and is measured across the cylinder.
piston stroke
The distance the piston slides up or down from the TDC to the BDC
Net horsepower
The maximum power avaliable from the engine when all acessories are turned on.
frictional horsepower
The power lost due to friction
Mommentum
The product of an object's mass and velocity
thermal efficiency
The ratio of how effectivly an engine converts fuel into usable work.
Swept Volume
The swept volume of the number cylinders. This is determined by multiplying.
Inertia
The tendency of an object to resist a change in motion
Crank Throw
The throw of the rod journal.
Brake Horsepower
The usable horsepower at the crankshaft
engine displacement
The volume displaced by all the pistons in an engine.
What is cylinder displacement?
The volume that the piston displaces from TDC to BDC
purpose
To measure how much torque an engine can produce.
Engine Dynamometer
Used to measure the brake horsepower of modern car engines
How is pressure measured?
a barometer in pounds per inch
horsepower
a measure of an engine's power based on how much weight a horse can pull
BMEP
brake mean effective pressure
How do you determine the effciency of an engine?
by pressure
Volumetric efficiency
the efficiency with which the engine can move the charge of fuel and air into and out of the cylinders
What is Mean Effective Pressure?
the pressure within the cylinder that increases during the compression stroke and becomes highest after ignition.
Power
the rate of doing work
How is temperature measured?
thermometer
