Skip to main content

Popular posts from this blog

AIR TEMPERATURE  Temperature and Temperature Scales  The temperature of a substance is a measure of how hot or cold it is. Two systems are said to have equal temperatures only if there is no change in any of their observable thermal characteristics when they are brought into contact with each other. Various temperature scales commonly used to measure the temperature of various substances are illustrated in Fig. 2.2. In conventional inch-pound (I-P) units, at a standard atmospheric pressure of 14.697 psia (101,325 Pa), the Fahrenheit scale has a freezing point of 32°F (0°C) at the ice point, and a boiling point of 212°F (100°C). For the triple point with a pressure of 0.08864 psia (611.2 Pa), the magnitude on the Fahrenheit scale is 32.018°F (0.01°C). There are 180 divisions, or degrees, between the boiling and freezing points in the Fahrenheit scale. In the International System of Units (SI units), the Celsius or Centigrade scale has a freezing point of 0°C and a boilin...
Post a Comment
Read more

how to work refrigeration cycle work

How Does an Air Conditioner Work? There are  two laws of physics  that we should review before explaining the inner workings of your air conditioning system. Combined Gas Law The first is the relationship between pressure and temperature, known as  the combined gas law  since it combines  Boyle’s Law ,  Charles’s Law , and  Gay-Lussac’s Law : Boyle’s Law  states that the pressure-volume product is constant. Charles’s Law  shows that the volume is proportional to the absolute temperature. Gay-Lussac’s Law  says that the pressure is proportional to the absolute temperature. In simple English, the combined gas law says that whenever you heat up a gas, pressure also increases. And vice versa, whenever you pressurize a gas, heat also increases. If pressure increases, so does its temperature. This is why a tire heats up as you pump it with air. If pressure decreases, so does its temperature. This is why an aeros...
2 comments
Read more

POTENTIALS AND CHALLENGES

DISTRIBUTION OF SYSTEMS USAGE  According to surveys conducted in 1995 by the Department of Energy/Energy Information Administration (DOE/EIA) of the United States, for a total floor space of 58,772 million ft2 (5462 million m2 ) in commercial buildings in 1995 and for a total of 96.6 million homes in 1993 (among these, 74.1 million homes were air conditioned), the floor space, in million square feet, and the number of homes using various types of air conditioning systems are as follows: Much of the floor space may be included in more than one air conditioning system. Given the possibility that the floor space may be counted repeatedly, the original data listed in the DOE/EIA publication were modified. The 8 percent of the space system includes part in central hydronic systems and part in unitary packaged systems. Among the air conditioned homes in 1993, the unitary packaged system is the predominate air conditioning system in U.S. homes. HISTORICAL DEVELOPMENT The his...
Post a Comment
Read more