Heating System & Cooling System Flashcards
BLEED AIR HEAT SYSTEM USES _______________ IN HELICOPTER CABINS TO COMBINE BLEED AIR WITH CABIN AIR.
MINI-EJECTORS
SOME TURBINE-POWERED AIRCRAFT NOT EQUIPPED WITH AIR CYCLE SYSTEMS STILL MAKE USE OF ______________________ TO HEAT THE CABIN.
ENGINE COMPRESSOR BLEED AIR
TEMPERATURES AT HIGH ALTITUDES IN WHICH AIRCRAFT OPERATE CAN BE WELL BELOW _____.
0 °F
______________________THAT USE AIR CYCLEAIR CONDITIONING SYSTEMSMIX BLEED AIR WITH COLD AIR PRODUCED BY THE ________________________________ TO OBTAIN WARM AIR FOR THE CABIN.
PRESSURIZED AIRCRAFT
AIR CYCLE MACHINE EXPANSION TURBINE
AIRCRAFT ___________ WITH AIR CYCLE AIR CONDITIONING MAY BE HEATED BY ONE OF A FEW POSSIBLE METHODS.
NOT EQUIPPED
THE BLEED AIR IS MIXED WITH AMBIENT AIR, OR CABIN RETURN AIR, AND DISTRIBUTED THROUGHOUT THE ______________________.
AIRCRAFT VIA DUCTING
THE MIXING OF AIR CAN BE DONE IN A VARIETY OF WAYS.
4 ways
- MIXING AIR VALVES
- FLOW CONTROL VALVES
- SHUTOFF VALVES
- VARIOUS CONTROL VALVES CONTROLLED BY SWITCHES IN THE COCKPIT
OCCASIONALLY, AN _____________________ IS USED TO HEAT THE AIRCRAFT.
ELECTRIC HEATING DEVICE
ELECTRICITY FLOWING THROUGH A _______________ MAKES THE ELEMENT WARM. A FAN TO BLOW AIR OVER THE ELEMENTS AND INTO THE CABIN IS USED TO TRANSFER THE HEAT.
HEATING ELEMENT
OTHER ___________________ SIMPLY RADIATE HEAT TO WARM THE CABIN.
FLOOR OR SIDEWALL ELEMENTS
_______________________________ REQUIRE A SIGNIFICANT AMOUNT OF THE AIRCRAFT’S GENERATOR OUTPUT, WHICH IS BETTER DEDICATED TO THE OPERATION OF OTHER ELECTRICAL DEVICES. FOR THIS REASON, THEY ARE NOT VERY COMMON. HOWEVER, THEIR USE ON THE GROUND WHEN POWERED BY A GROUND ELECTRICAL POWER SOURCE PREHEATS THE CABIN BEFORE PASSENGERS BOARD AND DOES NOT TAX THE ELECTRICAL SYSTEM.
ELECTRIC HEATING ELEMENT HEATERS
MOST ________________ LIGHT AIRCRAFT USE EXHAUST SHROUD HEATING SYSTEMS TO HEAT THE CABIN.
SINGLE-ENGINE
AMBIENT AIR IS DIRECTED INTO A METAL SHROUD, OR JACKET, THAT ENCASES PART OF THE ENGINE’S_________________. THE AIR IS WARMED BY THE EXHAUST AND DIRECTED THROUGH A FIREWALL HEATER VALVE INTO THE CABIN. THIS SIMPLE SOLUTION REQUIRES NO ELECTRICAL OR ENGINE POWER AND IT MAKES USE OF HEAT THAT WOULD OTHERWISE BE WASTED.
EXHAUST SYSTEM
MOST INVOLVE PRESSURIZING THE EXHAUST SYSTEM WITH AIR, WHILE INSPECTING FOR LEAKS WITH A _________________. SOME REQUIRE THE EXHAUST TO BE REMOVED AND PRESSURIZED WHILE SUBMERGED UNDER WATER TO DETECT ANY LEAKS.
SOAPY SOLUTION
FREQUENCY OF EXHAUST HEAT LEAK DETECTION CAN BE EVERY _____ HOURS.
100
_________________ ARE SIMILAR TO EXHAUST SHROUD HEATERS IN THAT AMBIENT AIR IS HEATED AND SENT TO THE CABIN. THE SOURCE OF HEAT IN THIS CASE IS AN INDEPENDENT COMBUSTION CHAMBER LOCATED INSIDE THE CYLINDRICAL OUTER SHROUD OF THE HEATER UNIT. THE CORRECT AMOUNT OF FUEL AND AIR ARE IGNITED IN THE AIR-TIGHT INNER CHAMBER. THE EXHAUST FROM COMBUSTION IS FUNNELED OVERBOARD.
COMBUSTION HEATERS
AMBIENT AIR IS DIRECTED BETWEEN THE COMBUSTION CHAMBER AND THE OUTER SHROUD. IT ABSORBS THE COMBUSTION HEAT BY _________ AND IS CHANNELED INTO THE CABIN.
CONVECTION
5 Types of aircraft heating system
Bleed air systems
electric heating systems
exhaust shroud haters
combustion heaters
ventilating air system
A major concern of exhaust shroud heat systems is the possibility that exhaust gases could __________ the cabin air
Contaminate
Occasionally, the exhaust system is slightly modified in a shroud heat configuration. For example, an exhaust muffler may have numerous ________ attached, which increase heat transfer to the cabin air
welded studs
Regardless of age or condition, aircraft with exhaust shroud heating systems could contain a _____________________ in the cockpit
carbon monoxide detection device
An aircraft ______________ is used on many small to medium sized aircraft. It is a heat source independent from the aircraft’s engine
Combustion heater
Combustion heaters are manufactured by a few different companies that supply the aviation industry. The most up-to-date units have ______________ and ________________.
electronic ignition and temperature control switches
______________ is the name of the air that is warmed and sent into the cabin. Typically, it comes into the combustion heater through a ram air intake.
Ventilating air
When the aircraft is on the ground, a ventilating air fan controlled by a ___________________ operates to draw in the air.
landing gear squat switch
Aircraft cooling systems also called _________________ are used to reduce the temperature inside an aircraft for crew and passenger comfort
air conditioning systems
The two basic methods of reducing the temperature of aircraft are the _______________ and the ______________.
Freon Vapor-Cycle machine and the Air-Cycle Machine
The ________________ is a closed system using the evaporation and condensation of freon to remove heat from the cabin interior
Vapor - cycle machine
The ____________ uses the compression and expansion of air to lower the temperature of the cabin air
Air - cycle machine
The ________ heat exchanger cools the engine/APU bleed air
Primary
The _______ heat exchanger removes the heat of compression of the ACM
Secondary
An air cycle machine (ACM) is the refrigeration unit of the _________________ used in pressurized gas turbine-powered aircraft. Normally an aircraft has two or three of these ACM.
environmental control system (ECS)
Each ACM and its components are often referred as an _______________.
air conditioning pack
The _____________________ is used in reciprocating engine powered aircraft and in smaller turboprop aircraft that do not make use of air-cycle machines to reduce the cabin interior temperature
vapor-cycle air-conditioning system
The operation of ____________ is controlled by the pilot and may incorporate automatic cutout or interrupt systems
vapor cycle machine
This ____________________ are used to disengage the refrigerant compressor during demand for high engine power output, such as during takeoff operations or when one engine of multi engine aircraft has failed
cutout and interrupt systems
This _________ in compressor operation allows all available power to be used to maintain controllable flight
Interruption
In aircraft basic science, where the nature of gases is discussed, it is shown that the temperature of a gas is _______ proportional to its pressure and volume
Directly
As a liquid change to gas (or are vaporized), they absorbed heat. This heat is called the ___________
latent heat of vaporization
A vapor cycle cooling system takes advantage of these laws of nature using two heat-exchangers to control the temperature of the _____ and _____
cockpit and cabin
One heat exchanger works in a fashion similar to the one previously discussed, taking heat from the closed system, and is called an ________
evaporator
The other heat exchanger draws heat from the air and adds it to the closed system. This heat exchanger is called a _______
condenser
The cooling process starts at the _______, where the refrigerant is in a gaseous form
compressor
The function of the compressor is to ______________, under pressure through the entire system as the gas enters the condenser it is drawn from the refrigerant and passed to the atmosphere
push the refrigerant
A system of this type usually employs Refrigerant 12, also known as _______, as the refrigerant
Freon 12
The refrigeration cycle, beginning with the _______ involves the impression of the refrigerant gas which is comparatively cold and at a low pressure as it leaves the evaporator and flows to the compressor
compressor
The ________ is the source of energy required for the operation of the system
compressor
From the compressor, the hot, high-pressure gas (vapor) flows into the _________, which is a heat radiator through which cool air is passed to remove heat from the vapor.
condenser
The _____________ is essentially a reservoir containing a filter and a desiccant
receiver-dryer-filter
A ________ is usually located on top of the receiver to allow observation of the fluid flow through the unit.
Sight glass
Modern large turbine-powered aircraft make use of ______________ to adjust the temperature of the air directed into the passenger and crew compartments of these large aircraft
air cycle machines
These large aircraft utilize air cycle cooling because of its simplicity, freedom from troubles and economy. In these systems, the refrigerant is ___.
air
