Term
| what effect does excessive heat have on reciprocating engines |
|
Definition
shortens life of engine parts,
changes behavior of combustion, and
impairs lubrication |
|
|
Term
| what is the purpose of cooling fans |
|
Definition
| provide a larger cooling surface area for removing heat from cylinder heads of air-cooled recip engines |
|
|
Term
| what are the reasons for using engine cowlings, baffles and cowl air seals |
|
Definition
reduces drag, and
helps direct airflow over cylinders for cooling |
|
|
Term
| what is the purpose of cowl flaps and how are they operated |
|
Definition
| control the amount of airflow through the cowling, they are mechanically, electrically or hydraulically operated |
|
|
Term
| how does an augmenter cooling system work |
|
Definition
| an outer tube placed over the exiting exhaust gas creates a venturi effect that draws more airflow over the engine |
|
|
Term
| where should cowl flaps be positioned for ground operations |
|
Definition
|
|
Term
| what type of power is used to operate cowl flaps |
|
Definition
manual
hydraulic or
electrical |
|
|
Term
| what should be done when cooling fin damage is discovered |
|
Definition
| depending on the damage some cooling fins can be repaired or in extreme cases the cylinder should be replaced |
|
|
Term
| why is cowl flap adjustment important |
|
Definition
| the movement must be within tolerances to keep cylinder head temp. within allowable limits |
|
|
Term
| how are turbine engines cooled |
|
Definition
by air passing through the engine
75% cooling
25% combustion |
|
|
Term
| in a turbine engine, where does bleed air come from that is used to cool bearings and other parts |
|
Definition
|
|
Term
| what is the relationship between turbine engine upper temp. limits and power produced |
|
Definition
| the higher the combustion temp. the more power it is capable of producing |
|
|
Term
| what is the approximate % of air passing through a turbine engine that is used for cooling rather than combustion |
|
Definition
|
|
Term
| what can be done to effectively allow higher gas temp. in the turbine section of some engines |
|
Definition
| compressor bleed air ducted through hollow sections in the turbine inlet guide vanes and first stage rotor blades can lower temp. enough to prevent heat damage |
|
|
