Stationary Engine Fundamentals
How efficient are most engines?
25 - 35%
1 HP equals how many watts?
746 watts
What is the formula for piston displacement?
Area of the bore multiplied by the length of stroke.
Torque produced by the engine is dependent on what?
BMEP (Break mean effective pressure)
The thermal efficiency of an engine is best described as the ability of the engine is to what?
Change the energy in the fuel to usable heat energy and power
Blowby happens on what two strokes of the engine?
Compression stroke and power stroke
A 2 stroke engine makes twice as much power as a 4 stroke engine of the same capacity. True or False?
False
Integral engines require proper alignment with the driven equipment. True or False?
False
Indicated horsepower is the power at the flywheel of the engine. True or False? and why?
False. Indicated horsepower is the theoretical power of an engine.
The classification for an engine with normal operating speed of 800 rpm is a low speed engine. True or False?
False. It's considered medium speed
The basic requirement for combustion are air, spark and compression. True or false? If not what are they?
False. They are Fuel, air and ignition
What does stroke equal when talking about the crankshaft?
It equals two times the throw distance of the crankshaft
Where is brake horsepower measured and what is it?
It is measured at the flywheel or the end of the crankshaft and is the actual engine power
The SI metric system measures pressure in what?
Pascals
The description of compression ratio is best stated as
The cylinder volume plus the displacement volume. Divided by the clearance volume
An undersquare engine is an engine with a larger stroke than bore. True or False?
True
At the end of the exhaust stroke, the intake and exhaust valves are open at the same time. True or False?
True
The amount of air an engine is able to take into the cylinder compared with the volume of the cylinder is called what?
Volumetric efficiency
What are the units potentially used for piston displacement?
inches cubed, centimeters cubed and liters
What are the 3 speed classifications for industrial engines?
low speed = 500 rpm or less Medium speed = 500-1000 rpm High speed = 1000 rpm or more
When you are determining engine rotation using the SAE standard, you view the engine from what?
the main power end of the engine (Flywheel)