The variable speed control of the chilled water pumps achieves an additional chilled water plant. power savings of around 5% [2]. These systems put even more demands on the variable speed chiller control. system, while not affecting the fixed-speed control system at all. However, the difference in compressor map.
The density of dry air can be calculated using the ideal gas law, expressed as a function of temperature and pressure: where: The specific gas constant for dry air is 287.058 J/(kgÂ·K) in SI units, and 53.35 (ftÂ·lbf)/(lbmÂ·Â°R) in United States customary and Imperial units. This quantity may vary slightly depending on the molecular composition of air at a particular location.
The Gas Constant (R). The gas constant is measure of the weight of the number of molecules of a gas. In the atmosphere around us we have air which is about 78% Nitrogen (N 2) , about 21% Oxygen (O 2) and about 1% other gases. Nitrogen has a molecular weight of 14 so a N 2 molecule has a molecular weight of 28.Oxygen has a molecular weight of 16 so an O 2 molecule has a molecular weight of 32. Given the mixture of gases found in air the average molecular weight of air is around 29.Water is made up of two hydrogen and one oxygen atoms (H 2 O). Hydrogen is the lightest element and has a molecular weight of one.So a water molecule has a molecular weight of 18 (2 * 1 + 1 * 16 = 18). Water is a very light molecule and much lighter than the average weight of the molecules found in air.xygen has a molecular weight of 16 so an O 2 molecule has a molecular weight of 32. Given the mixture of gases found in air the average molecular weight of air is around 29. Water is made up of two hydrogen and one oxygen atoms (H 2 O).