# Compressor Approximate Application Ranges

Approximate application ranges in terms of ICFM and discharge pressure for four categories of compressors can be quickly approximated using Figure 100-11. Figures 100-12 through…

# Compressor Gas Analysis

A gas analysis should be provided for all present and future operating conditions, and it should be checked for the presence of sulfides, chlorides, or…

# Compressor Characteristic Curve

General characteristic curves for the four types of compressors at constant speed are shown in Figure 100-10.

# Compressor System Resistance Curve

The system resistance met by a compressor can vary from a constant discharge pressure to a variable relationship as shown in the generalized system resistance…

# Compressor Duty

The first step in specifying compressors is to define the required compression duty. This includes defining: • flow rate • gas composition • suction pressure…

# Polytropic Compression

Polytropic compression is commonly assumed for dynamic (centrifugal and axial) compressors. The previous discussion of the adiabatic process showed that its relationships need mathematical corrections…

# Thermodynamic Diagrams

Thermodynamic-property diagrams account directly for deviations of a real gas from ideal relationships. These diagrams are a plot of gas properties, commonly including: enthalpy, entropy,…

# Adiabatic Relationships

Isentropic means constant entropy (a definition of entropy is beyond the scope of this manual). Adiabatic describes a process wherein no heat is added or…

# Isothermal Compression

In an isothermal process, the temperature is unchanged during compression. Although it is impossible to build a machine that will compress isothermally, isothermal performance is…

# Comparison of the Isothermal, Isentropic and Polytropic Processes

The two actual methods used to calculate thermodynamic relationships are isentropic (adiabatic) and polytropic. These calculations are the basis for determining capacity, driver size, and…