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 mass, m, of the substance in lbm is equal to n times the molecular weight, i.e., m = nM. Specific gas constant ï· The specific gas constant (R, sometimes R gas) is not universal, and its value depends on the specific gas being considered. R is defined as the universal gas constant divided by the molecular weight of the substance, u RRM ï½ . The dimensions of R are not the same as those of R u, since molecular weight is a not a dimensionless quantity, although some authors treat it as such.