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Transparent Area Washing Systems for Aircraft

1997-10-01
HISTORICAL
AIR1102A
This information report presents data and recommendations pertaining to the design and development of transparent area washing systems for aircraft.
Standard

Thermodynamics of Incompressible and Compressible Fluid Flow

2017-12-27
WIP
AIR1168/1A
The fluid flow treated in this section is isothermal, subsonic, and incompressible. The effects of heat addition, work on the fluid, variation in sonic velocity, and changes in elevation are neglected. An incompressible fluid is one in which a change in pressure causes no resulting change in fluid density. The assumption that liquids are incompressible introduces no appreciable error in calculations, but the assumption that a gas is incompressible introduces an error of a magnitude that is dependent on the fluid velocity and on the loss coefficient of the particular duct section or price of equipment. Fit 1A-1 shows the error in pressure drop resulting from assuming that air is incompressible. With reasonably small loss coefficients and the accuracy that is usually required in most calculations, compressible fluids may be treated as incompressible for velocities less than Mach 0.2.
Standard

Aerothermodynamic Systems Engineering and Design

1989-09-01
CURRENT
AIR1168/3
This section presents methods and examples of computing the steady-state heating and cooling loads of aircraft compartments. In a steady-state process the flows of heat throughout the system are stabilized and thus do not change with time. In an aircraft compartment, several elements compose the steady-state air conditioning load. Transfer of heat occurs between these sources and sinks by the combined processes of convection, radiation, and conduction in the following manner: Convection between the boundary layer and the outer airplane skin. Radiation between the external skin and the external environment. Solar radiation through transparent areas directly on flight personnel and equipment and on the cabin interior surfaces. Conduction through the cabin walls and structural members. Convection between the interior cabin surface and the cabin air. Convection between cabin air and flight personnel or equipment.
Standard

Heat and Mass Transfer and Air-Water Mixtures

2011-07-25
CURRENT
AIR1168/2A
Heat transfer is the transport of thermal energy from one point to another. Heat is transferred only under the influence of a temperature gradient or temperature difference. The direction of heat transfer is always from the point at the higher temperature to the point at the lower temperature, in accordance with the second law of thermodynamics. The fundamental modes of heat transfer are conduction, convection, and radiation. Conduction is the net transfer of energy within a fluid or solid occurring by the collisions of molecules, atoms, or electrons. Convection is the transfer of energy resulting from fluid motion. Convection involves the processes of conduction, fluid motion, and mass transfer. Radiation is the transfer of energy from one point to another in the absence of a transporting medium. In practical applications several modes of heat transfer occur simultaneously.
Standard

Heat and Mass Transfer and Air-Water Mixtures

2001-08-01
HISTORICAL
AIR1168/2
Heat transfer is the transport of thermal energy from one point to another. Heat is transferred only under the influence of a temperature gradient or temperature difference. The direction of heat transfer is always from the point at the higher temperature to the point at the lower temperature, in accordance with the second law of thermodynamics. The fundamental modes of heat transfer are conduction, convection, and radiation. Conduction is the net transfer of energy within a fluid or solid occurring by the collisions of molecules, atoms, or electrons. Convection is the transfer of energy resulting from fluid motion. Convection involves the processes of conduction, fluid motion, and mass transfer. Radiation is the transfer of energy from one point to another in the absence of a transporting medium. In practical applications several modes of heat transfer occur simultaneously.
Standard

Spacecraft Life Support Systems

2012-10-15
CURRENT
AIR1168/14A
A life support system (LSS) is usually defined as a system that provides elements necessary for maintaining human life and health in the state required for performing a prescribed mission. The LSS, depending upon specific design requirements, will provide pressure, temperature, and composition of local atmosphere, food, and water. It may or may not collect, dispose, or reprocess wastes such as carbon dioxide, water vapor, urine, and feces. It can be seen from the preceding definition that LSS requirements may differ widely, depending on the mission specified, such as operation in Earth orbit or lunar mission. In all cases the time of operation is an important design factor. An LSS is sometimes briefly defined as a system providing atmospheric control and water, waste, and thermal management. The major subsystems required to accomplish the general functions mentioned above are: Breathing and pressurization gas storage system. Temperature and humidity control system.
Standard

Spacecraft Equipment Environmental Control

2011-07-25
CURRENT
AIR1168/13A
This part of the manual presents methods for arriving at a solution to the problem of spacecraft inflight equipment environmental control. The temperature aspect of this problem may be defined as the maintenance of a proper balance and integration of the following thermal loads: equipment-generated, personnel-generated, and transmission through external boundary. Achievement of such a thermal energy balance involves the investigation of three specific areas: Establishment of design requirements. Evaluation of properties of materials. Development of analytical approach. The solution to the problem of vehicle and/or equipment pressurization, which is the second half of major environmental control functions, is also treated in this section. Pressurization in this case may be defined as the task associated with the storage and control of a pressurizing fluid, leakage control, and repressurization.
Standard

Spacecraft Life Support Systems

1994-01-01
HISTORICAL
AIR1168/14
A life support system (LSS) is usually defined as a system that provides elements necessary for maintaining human life and health in the state required for performing a prescribed mission. The LSS, depending upon specific design requirements, will provide pressure, temperature, and composition of local atmosphere, food, and water. It may or may not collect, dispose, or reprocess wastes such as carbon dioxide, water vapor, urine, and feces. It can be seen from the preceding definition that LSS requirements may differ widely, depending on the mission specified, such as operation in Earth orbit or lunar mission. In all cases the time of operation is an important design factor. An LSS is sometimes briefly defined as a system providing atmospheric control and water, waste, and thermal management. The major subsystems required to accomplish the general functions mentioned above are: Breathing and pressurization gas storage system. Temperature and humidity control system.
Standard

Spacecraft Equipment Environmental Control

1999-11-01
HISTORICAL
AIR1168/13
This part of the manual presents methods for arriving at a solution to the problem of spacecraft inflight equipment environmental control. The temperature aspect of this problem may be defined as the maintenance of a proper balance and integration of the following thermal loads: equipment-generated, personnel-generated, and transmission through external boundary. Achievement of such a thermal energy balance involves the investigation of three specific areas: Establishment of design requirements. Evaluation of properties of materials. Development of analytical approach. The solution to the problem of vehicle and/or equipment pressurization, which is the second half of major environmental control functions, is also treated in this section. Pressurization in this case may be defined as the task associated with the storage and control of a pressurizing fluid, leakage control, and repressurization.
Standard

Aerospace Pressurization System Design

2011-07-25
CURRENT
AIR1168/7A
The pressurization system design considerations presented in this AIR deal with human physiological requirements, characteristics of pressurization air sources, methods of controlling cabin pressure, cabin leakage control, leakage calculation methods, and methods of emergency cabin pressure release.
Standard

Characteristics of Equipment Components, Equipment Cooling System Design, and Temperature Control System Design

1993-04-01
HISTORICAL
AIR1168/6
This section relates the engineering fundamentals and thermophysical property material of the previous sections to the airborne equipment for which thermodynamic considerations apply. For each generic classification of equipment, information is presented for the types of equipment included in these categories, and the thermodynamic design considerations with respect to performance, sizing, and selection of this equipment.
Standard

Aerothermodynamic Test Instrumentation and Measurement

1990-02-01
HISTORICAL
AIR1168/5
Like the technologies to which it contributes, the science of instrumentation seems to be expanding to unlimited proportions. In considering instrumentation techniques, primary emphasis was given in this section to the fundamentals of pressure, temperature, and flow measurement. Accent was placed on common measurement methods, such as manometers, thermocouples, and head meters, rather than on difficult and specialized techniques. Icing, humidity, velocity, and other special measurements were touched on briefly. Many of the references cited were survey articles or texts containing excellent bibliographies to assist a more detailed study where required.
Standard

Thermophysical Characteristics of Working Fluids and Heat Transfer Fluids

2017-05-19
CURRENT
AIR1168/10A
This AIR is arranged in the following two sections: 2E - Thermodynamic Characteristics of Working Fluids, which contains thermodynamic diagrams for a number of working fluids currently in use and supplied by various industrial firms. 2F - Properties of Heat Transfer Fluids, which contains data, primarily in graphical form, on fluids that are frequently used in fluid heat transfer loops. Other properties of the environment, gases, liquids, and solids, can be found, as follows, in AIR1168/9: 2A-Properties of the Natural Environment 2B-Properties of Gases 2C-Properties of Liquids 2D-Properties of Solids
Standard

THERMOPHYSICAL CHARACTERISTICS OF WORKING FLUIDS AND HEAT TRANSFER FLUIDS

1992-04-01
HISTORICAL
AIR1168/10
This AIR is arranged in the following two sections: 2E - Thermodynamic Characteristics of Working Fluids, which contains thermodynamic diagrams for a number of working fluids currently in use and supplied by various industrial firms. 2F - Properties of Heat Transfer Fluids, which contains data, primarily in graphical form, on fluids that are frequently used in fluid heat transfer loops. Other properties of the environment, gases, liquids, and solids, can be found, as follows, in AIR1168/9: 2A-Properties of the Natural Environment 2B-Properties of Gases 2C-Properties of Liquids 2D-Properties of Solids
Standard

Thermodynamics of Incompressible and Compressible Fluid Flow

1989-03-01
CURRENT
AIR1168/1
The fluid flow treated in this section is isothermal, subsonic, and incompressible. The effects of heat addition, work on the fluid, variation in sonic velocity, and changes in elevation are neglected. An incompressible fluid is one in which a change in pressure causes no resulting change in fluid density. The assumption that liquids are incompressible introduces no appreciable error in calculations, but the assumption that a gas is incompressible introduces an error of a magnitude that is dependent on the fluid velocity and on the loss coefficient of the particular duct section or piece of equipment. Fig. 1A-1 shows the error in pressure drop resulting from assuming that air is incompressible. With reasonably small loss coefficients and the accuracy that is usually required in most calculations, compressible fluids may be treated as incompressible for velocities less than Mach 0.2.
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