Book 2 - Burners Flashcards
to alleviate ___-spots in the combustion section and turbine due to effect of ________ on the fuel in the burner rail, _______, sometimes ______-loaded, are put into the burner rial to equalise the fuel flow around the burners
to alleviate HOT-spots in the combustion section and turbine due to effect of GRAVITY on the fuel in the burner rail, WEIGHTS, sometimes SPRUNG-loaded, are put into the burner rial to equalise the fuel flow around the burners
the fuel flow from the FCU can either be a ______ stream, or a _______ stream. when there is a double stream, the streams are called ________ and ____. primary is always available when the HP ____ is open and main will join it when sufficient ________ has been built up in the system. ____ carries the bulk of the fuel at normal running RPM’s and can usually be identified by larger _________ on the burner rail
the fuel flow from the FCU can either be a SINGLE stream, or a DOUBLE stream. when there is a double stream, the streams are called PRIMARY and MAIN. primary is always available when the HP COCK is open and main will join it when sufficient PRESSURE has been built up in the system. MAIN carries the bulk of the fuel at normal running RPM’s and can usually be identified by larger DIAMETER on the burner rail
where there are two fuel flows, a ____________ valve can be fitted against the main flow to ensure a high enough _________ in the primary flow to provide adequate _____________ at lower fuel pressures. on other systems, this is achieved by _______-loading the distributor weights in the distribution system
the other occasion where a pressurising valve may be fitted, is to ensure an adequate ________ pressure in the fuel _______ systems, in which case it is renamed a ____-pressure valve and can be seen in either single or partial ______ flow systems.
where there are two fuel flows, a PRESSURISING valve can be fitted against the main flow to ensure a high enough PRESSURE in the primary flow to provide adequate ATOMISATION at lower fuel pressures. on other systems, this is achieved by SPRING-loading the distributor weights in the distribution system
the other occasion where a pressurising valve may be fitted, is to ensure an adequate WORKING pressure in the fuel CONTROL systems, in which case it is renamed a BACK-pressure valve and can be seen in either single or partial DOUBLE flow systems.
burners are fitted to ______ the fuel into the combustion chambers in such a way as to ensure rapid burning and to give a ______ flame
burners are fitted to INJECT the fuel into the combustion chambers in such a way as to ensure rapid burning and to give a STABLE flame
what are the two main types of burners?
- atomising
- vaporising
vaporising type burners vaporise the fuel by pre-_______ it prior to combustion. they are generally known as _______-stick burners
vaporising type burners vaporise the fuel by pre-HEATING it prior to combustion. they are generally known as HOCKEY-stick burners
atomising type burners atomise the fuel by passing it through a _____ chamber where ___________ disposed holes or slots impart swirl to the fuel by converting its pressure into _______ energy. the fuel then passes through the ________ orifice where the swirl motion is removed and the fuel is atomised to produce a ____-shaped spray
at low pressures, a continuous flow of fuel is formed, called a _______
at intermediate pressures, the flow begins to break up and is called a _____
at high pressures, the tulip shortens and becomes a finely atomised spray
atomising type burners atomise the fuel by passing it through a SWIRL chamber where TANGENTIALLY disposed holes or slots impart swirl to the fuel by converting its pressure into KINETIC energy. the fuel then passes through the DISCHARGE orifice where the swirl motion is removed and the fuel is atomised to produce a CONE-shaped spray
at low pressures, a continuous flow of fuel is formed, called a BUBBLE
at intermediate pressures, the flow begins to break up and is called a TULIP
at high pressures, the tulip shortens and becomes a finely atomised spray
simplex burners, used where there is only ___ flow of fuel
simplex burners, used where there is only ONE flow of fuel
duplex burners require two flows, one ____ and one _______. each flow has an independent orifice, a smaller (______) one for the primary and a larger (_______) orifice for the main flow
duplex burners require two flows, one MAIN and one PRIMARY. each flow has an independent orifice, a smaller (CENTRAL) one for the primary and a larger (ANNULAR) orifice for the main flow
spray nozzles carry a proportion of the primary combustion ___ with the injected fuel. by aerating the spray, the load fuel rich concentrations produced by other types of burners are avoided, leading to a _________ in carbon formation and exhaust smoke.
also, due to lower fuel ________ required for atomisation, a lighter ____-type pump is permitted
spray nozzles carry a proportion of the primary combustion AIR with the injected fuel. by aerating the spray, the load fuel rich concentrations produced by other types of burners are avoided, leading to a REDUCTION in carbon formation and exhaust smoke.
also, due to lower fuel PRESSURE required for atomisation, a lighter GEAR-type pump is permitted
an airspray nozzle is an development of the spray nozzle, using air to _____ the fuel instead of tangential slots, thereby creating more _________ atomisation
an airspray nozzle is an development of the spray nozzle, using air to SWIRL the fuel instead of tangential slots, thereby creating more EFFICIENT atomisation
for all types of burners, the primary air being used for combustion is compressor ________ air at high temperatures - possibly ___-___ celsius
for all types of burners, the primary air being used for combustion is compressor DELIVERY air at high temperatures - possibly 500-600 celsius
burners often come as a ______ set and should only be replaced individually with the permission of the manufacturer
burners often come as a MATCHED set and should only be replaced individually with the permission of the manufacturer
