Detailed explanation of core parameters of centrifugal compressor

As the core power equipment in modern industry, centrifugal compressor’s running state directly determines the consistency and economy of production process. To master this equipment, we must deeply understand its key parameters. These parameters are not only the basis of design and manufacture, but also the important basis for user selection, monitoring and optimization maintenance.
Detailed explanation of core parameters of centrifugal compressor: key indicators from type selection to operation
I. Basic performance parameters
1. Flow parameters
Flow rate is the core index to measure the conveying capacity of compressor, which is divided into two forms:
Volume flow: the volume of gas passing through the inlet cross section per unit time, usually in m3/min or nm3/h.. This value is greatly influenced by the intake state.
Mass flow: the mass of gas passing through the compressor in unit time, measured in kg/s or t/h. It is more critical in process calculation, because it directly reflects the total amount of medium transportation.
2. Pressure parameters
The pressure parameter reflects the “work capacity” of the compressor;
Exhaust pressure: the gas pressure at the outlet must meet the requirements of the process pipe network.
Pressure ratio: the ratio of exhaust pressure to intake pressure, reflecting the degree of gas compression. Multi-stage compressor realizes high total pressure ratio through step-by-step compression.
3. Power parameters
Shaft power: the actual power required by the compressor spindle is the basis for selecting the driving machine.
Internal power: the power directly used for gas compression, reflecting the pneumatic perfection of the compressor.
Specific power: the power consumed per unit flow is an important comparison index for evaluating energy efficiency.
Second, the structural parameters
1. Series and number of paragraphs
Stage: consists of an impeller and its supporting fixed components.
Section: compression stage group that completes primary intermediate cooling.
2. Import and export dimensions
Determine the interface size and pipeline configuration, which will affect the flow loss of the system.
3. Design speed
The critical speed design of rotor system directly affects the stability and reliability of operation.
Correlation between parameters and engineering application
These parameters do not exist in isolation, but are interrelated and constrained as a whole. For example:
The change of flow rate will cause the corresponding changes of pressure, power and efficiency.
Speed adjustment will change the position of the whole performance curve.
The change of intake conditions (pressure, temperature, medium composition) will affect the actual operating parameters.
In practical engineering, it is necessary to:
Correct selection of rated parameter points to make them fall within the high efficiency zone.
Parameter variation range considering variable operating conditions.
Ensure that the operating point is far away from dangerous working conditions such as surge.
Give consideration to initial investment and long-term operation cost.
The above is a detailed explanation of the core parameters of centrifugal compressor. Mastering the parameters of centrifugal compressor is just like reading the “language” of equipment. Only by deeply understanding the technical connotation and relationship of each parameter can we make a scientific selection decision and realize the stable operation of the equipment.