Tecnico Alvarado

AIR CONDITIONING

ATMOSPHERIC AIR IS A MIXTURE OF GASES AND VAPORS.ANY SUBSTANCE WHICH FOLLOWS
THE PERFECT GAS LAWS IS CALLED A PERFEC GAS OR SOME TIMES JUST A GAS.A GASEOUS SUBSTANCE WHICHDOES NOT FOLLOW THE PERFECT GAS LAWS IS CALLED VAPOR.IF THE GASEOUS SUBSTANCE IS SUPERHEATED SUFFICIENTLY (TO A TEMPERATURE HIGHER THAN THE SATURATION TEMPERATURE CORRESPONDING TO THE EXISTENPRESSURE) ITS PROPERTIES MAY BE APPROXIMATE BY THE PERFEC GAS LAWS.ALTHOUGH THIS DISCUSSION OF VAPORS AND GASES APPLIES, IN GENERAL, TO ANY GAS SUCH A FREON, OR ESTEAM, IT WILL BE REFERENCED WITH THESPECIFIC VALUES OF STEAM.
AS AN EXAMPLE, WATER AT 212 F AND 14.7 PSI A WILL BOIL OR VAPORIZE TO FORM VAPOR OR STEAM.THE PROPERTIES OF THIS VAPOR FORMED CAN NOT BE OBTAINED FROM THE PERFECT GAS LAWSBUT MUST BE OBTAINED FROM SPECIAL CHARTS OR TABLES CALLED THE MOLLIER DIAGRAM OR STEAM TABLES . AS HEAT CONTINUES APPLIED , THE VAPOR BECOMES SUPERHEATED AND ABOVE A CERTAIN POINT, WHICH IS NOT WELLDEFINED , THE VAPOR WILL NEARLY FOLLOW THE PERFEC GAS LAWS WHEN IN DOUBT AS TO WHERE TO APPLY THE PERFEC GAS LAWS , PV = WRT , THE APROXIMATION SHOULD BE MADE AT THAT POINT WHERE CHARTS OR TABLESCEASE TO RECORD INFORMATION .
IN AIR - CONDITIONING WORK, LAW STEAM PARTIAL PRESSURES ARE OBTAINED AT ROOM TEMPERATURES, CAUSING THE VAPORS TO BECOME SUPERHEATED, AND TO FOLLOW THE PERFECGAS LAWS. WATER VAPOR AT PRESSURES LESS THAN 1 ATMOSPHERE IS SUPER HEATED AND THEREFORE APPROXIMATELY A PERFEC GAS.
DALTON´S LAWS OF PARTIAL PRESSURES. IN A GIVEN MIXTURES OF GASES OR VAPORS , EACHGAS OR VAPOR EXERLS THE SAME PRESSURE IT WOULD EXERT IF OCCURRED ALONG IN THE SAME SPACE AND AT THE SAME TEMPERATURE AS EXISTS IN THE MIXTURE . WHENEVER A LIQUID HAS ANY SPACE ABOVE IT, OR WHENTHE PRESSURE ABOVETHE LIQUID IS REDUCED, SOME OF THE LIQUID VAPORIZES UNTIL THERE IS A CERTAIN PRESSURE AGAINGS BUOTH THE SURFACE THE LIQUID AND THE WALLS OF THE CONTAINER. THE PRESSURE AT WHICH THIS...