Understanding Polynomial equations and polynomial coefficients isn't really as difficult as it sounds. For compressor sizing, the equations are long and there are a lot of coefficients, but the process is made easier by the fact that the same thing is done over and over again.

You may not need these equations and coefficients in your daily work, but it's interesting to have at least a basic understanding of how they work and how they're used.

Background

To create a table or curve of compressor performance, manufacturers take a number of measurements. Cooling capacity, power usage, and current consumption are measured on a calorimeter at many different run conditions, using several compressors of the same model. A huge amount of data is collected from these measurements.