Fundamentals Of Diesel Engines, Heat Exchangers, Pumps And Valves

Quiz Questions:

   
1. The compression ratio is a measure of how much the engine compresses the gasses in the engine's cylinder. In a gasoline engine the compression ratio (which controls the compression temperature) is limited by the air-fuel mixture entering the cylinders.
       
    True
    False
       
2.

The crankshaft transforms the linear motion of the pistons into a rotational motion that is transmitted to the load. Crankshafts are made of forged steel. The forged crankshaft is machined to produce the crankshaft bearing and connecting rod bearing surfaces.

       
    True
    False
       
3. ____________ refers to the diameter of the engine's cylinder, and _________ refers to the distance the piston travels from the top of the cylinder to the bottom.
       
    Stroke, bore
    Bore, stroke
       
4. Turbo charging an engine occurs when the engine's own exhaust gasses are forced through a turbine (impeller), which rotates and is connected to a second impeller located in the fresh air intake system. The impeller in the fresh air intake system compresses the fresh air.
       
    True
    False
       
5. The ratio of an engine's brake horsepower and its indicated horsepower is called the ___________________ of the engine.
     
  Mechanical efficiency
  Electrical efficiency
       
 
Heat Exchangers:
   
6.

_________________ heat exchangers use the same fluid for heating and cooling.

       
    Regenerative
    Non-regenerative
       
7. Single-pass heat exchangers have fluids that pass each other more than once through the use of U tubes and baffles.
       
    True
    False
       
8. The most familiar example of an air-to liquid heat exchanger is a ____________________.
       
    Car radiator
    Inverter
       
9.

A vacuum pump may be any type of motor-driven air compressor. Its suction is attached to the condenser, and it discharges to the atmosphere.

       
    True
    False
       
10.

The __________________ is the area at the bottom of the condenser where the condensed steam is collected to be pumped back into the system feed water.

       
    Radiator
    Hotwell
       
11.

The purpose of a ______________________ is to remove the latent heat of vaporization, condensing the vapor into a liquid.

       
    Condenser
    Radiator
       
 
Pumps:
   
12. The purpose of the diffuser is to increase the efficiency of the centrifugal pump by allowing a more gradual expansion and less turbulent area for the liquid to reduce in velocity.
       
    True
    Fase
       
13.

The enclosed impeller is constructed with a circular plate (the web) attached to one side of the blades. The semi-open impeller has circular plates attached to both sides of the blades.

       
    True
    False
       
14.

What are the indications that a centrifugal pump has cavitations?

       
    Noise
    Fluctuating discharge pressure and flow
    Fluctuating pump motor current
    None of the above
    All of the above
       
15. Shutoff head is the ________________ that can be developed by a centrifugal pump operating at a set speed.
       
    Minimum head
    Maximum head
   
16.

A ________________ pump, sometimes referred to as a single pump, is a pump having a single liquid (pump) cylinder.

       
    Simplex
    Duplex
       
17.

Slippage is the rate at which the liquid leaks from the discharge of the pump back to the pump suction.

       
    True
    False
       
18.

Positive displacement pumps are protected from over pressurization by a relief valve on the upstream side of the pump discharge valve.

       
    True
    False
       
19.

The characteristic curve for a positive displacement pump operating at a certain speed is a _______________ on a graph of head versus flow.

       
    Horizontal line
    Vertical line
       
20.

As the viscosity of a liquid increases the maximum speed at which a reciprocating positive displacement pump operates decreases. Therefore, as viscosity increases, the maximum flow rate through the pump _____________.

       
    Decreases
    Increases