is the process of treating air so as to control simultaneously its temperature, humidity, cleanliness and distribution to meet the requirements of the conditioned space.
is to control the temperature, humidity, purity (that is, removal of dust and impurities) and air movement or circulation.
air conditioning
is the process of supplying or removing air by natural or mechanical means to or from any space. Such air may or may not have been conditioned.
ventilation
is the study of the properties of air
psychrometry
is an instrument used in the study of properties of air.
psychrometer
is air whose condition is such that any decrease in temperature will result in condensation of the water vapor into liquid.
saturated air
is air containing superheated vapor.
unsaturated air
is a binary mixture of dry air and water vapor.
moist air
is the non-condensing components of the mixture, mainly the Nitrogen and Oxygen.
dry air
is the condensable component of the mixture, the water vapor which may exist in a saturated or superheated state.
vapor
is the temperature of air as registered by an ordinary thermometer.
Dry bulb temperature
is the temperature of air as registered by a thermometer whose bulb is covered by a wetted wick and exposed to a current of rapidly moving air.
Wet bulb temperature
is the difference between the readings of the wet and dry bulb thermometers.
Wet bulb depression
is the saturation temperature corresponding to the actual pressure of the steam in air or the temperature at which condensation of moisture begins when the air is cooled at constant pressure.
Dew point temperature
the total pressure of air-water vapor mixture, is the sum of the partial pressures of dry air and water vapor.
Pressure
is the ratio of the mass of water vapor to the mass of dry air. It is also known as moisture content, mixing ratio or specific humidity.
Humidity ratio
is the ratio of the partial pressure of water vapor in the air to the saturation pressure corresponding to the temperature of the air.
Relative humidity
is the number of cubic meters of mixture per kilogram of dry air.
Specific volume
is the reciprocal of specific volume.
Density
is the enthalpy of the mixture of dry air and water vapor, and is the, and is the sum of the enthalpy of the dry air and enthalpy of the water vapor
Enthalpy
is a branch of science that deals with the process of cooling of a space or substance below the environmental temperature.
Refrigeration
is an assembly of four major components, namely, the compressor, condenser, expansion valve and the evaporator through which a very low boiling point substance flow in a cycle and absorbs heat from the immediate surroundings, thereby producing the cooling effect
Refrigeration system
is a sequence of thermodynamic processes whereby heat is withdrawn from a cold body and expelled to a hot body.
Refrigeration cycle
removal of heat by utilizing a refrigerant subjected to cycles of refrigerating thermodynamics and employing a mechanical compressor.
Mechanical Refrigeration
refrigerant gas evolved in the evaporator is taken up in an absorber and released in a generator upon the application of heat.
Absorption Refrigeration
uses air as refrigerant. In many aspect, air-cycle equipment is ideally suited for use in aircraft.
Air-Cycle Refrigeration
uses water as refrigerant.
Steam-Jet Refrigeration
Last changed2 months ago