![]() ![]() The specific humidity of air remains constant during a simple cooling process,īut its relative humidity increases. This is accomplished by passing the airįirst through a heating section and then through a humidifying section. Problems with the low relative humidity resulting from simple heating can beĮliminated by humidifying the heated air. Heating and cooling appear as a horizontal line since no moisture is added to or The air in these systems is heated by circulating it through aĭuct that contains the tubing for the hot gases or the electric resistance wires.Ĭooling can be accomplished by passing the air over some coils through which a Many residential heating systems consist of a stove, a heat pump, or an electric Simple Heating and Cooling ( = constant)ĭuring simple heating, specific humidity remainsĬonstant, but relative humidity decreases. Small relative to the other terms in the energy balance relation. The work term usually consists of the fan work input, which is Processes with the following general mass and energy balances: Most air-conditioning processes can be modeled as steady-flow Pressure, T wbis approximately equal to the These equations by measuring the pressureĪnd temperature of air at the inlet and theįor air–water vapor mixtures at atmospheric The enthalpy of moist (atmospheric) air isĮxpressed per unit mass of dry air, not per Pv Partial pressure of vapor (vapor pressure) Then theĪtmospheric air can be treated as an ideal-gas Water vapor in air behaves as if it existed aloneĪnd obeys the ideal-gas relation Pv = RT. Therefore, it is an important consideration Water vapor in the air plays a major role in humanĬomfort. DRY AND ATMOSPHERIC AIRĪtmospheric air: Air in the atmosphere containingĭry air: Air that contains no water vapor. ![]() Apply the principles of the conservation of mass and energy to various air-conditioning processes.Use the psychrometric chart as a tool to determine the properties of atmospheric air.Relate the adiabatic saturation temperature and wet-bulb temperatures of atmospheric air.Calculate the dew-point temperature of atmospheric air.Define and calculate the specific and relative humidity of atmospheric air.Differentiate between dry air and atmospheric air.Hassan ElattarĪdiabatic saturation and wet-bulb temperatures Thermodynamics II GAS–VAPOR MIXTURES AND AIR- CONDITIONING Dr. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |