Centrifugal Compressor - Fan Laws

This application uses the affinity laws to calculate the volume capacity, head when the speed of the impeller is changed. Understanding the ratio of specific heat for the gas being used in the compressor may present challenges.

Gas volume flow is proportional to the impeller rotation speed:

PTLB Compressors 2.4_Intro.png

 

Head is proportional to the square of the impeller rotation speed:

PTLB Compressors 2.4_Intro 2.png

 

Brake horsepower is proportional to the cube of the impeller rotation speed:

PTLB Compressors 2.4_Intro 3.png

𝑄1 βˆ’ Initial Flow[𝑀𝑀𝑆𝐢𝐹𝐷]
𝑄2 βˆ’ Final Flow[𝑀𝑀𝑆𝐢𝐹𝐷]
𝐻1 βˆ’ Initial Compressor head[ft β€’ lb/ lbm]
𝐻2 βˆ’ Final Compressor head[ft β€’ lb/ lbm]
𝐡𝐻𝑃1 βˆ’ Initial Brake Horsepower[HP]
𝐡𝐻𝑃2 βˆ’ Final Brake Horsepower[HP]
𝑛1 βˆ’ Initial Rotational Speed[rpm]
𝑛2 βˆ’ Final Rotational Speed[rpm]

 

Input Parameters

  1. To create a new case, click the β€œAdd Case” button
  2. Select the Centrifugal Compressor – Fan Laws application from the Pipeline Compressor module.
  3. Enter Case Name, Location, Date and any necessary notes.
  4. Fill out all required fields.
  5. Make sure the values you are inputting are in the correct units.
  6. Click the CALCULATE button.

  • Q1 – Initial Flow Rate(MMSCFD)
  • H1 – Initial Compressor Head (ft lbf/lbm)
  • BHP1 – Initial Shaft Horsepower(HP)
  • N1 – Initial Impeller Rotational Speed(rpm)
  • N2 – Final Impeller Rotational Speed(rpm)

PLTB Compressors 2.4_Input Rev_090120.png

 

Outputs/Reports

  1. View the results.
  2. If an input parameter needs to be edited be sure to hit the CALCULATE button after the change.
  3. To SAVE, fill out all required case details then click the SAVE button.
  4. To rename an existing file, click the SAVE As button. Provide all case info then click SAVE.
  5. To generate a REPORT, click the REPORT button.
  6. The user may export the Case/Report by clicking the Export to Excel/PowerPoint icon.
  7. To delete a case, click the DELETE icon near the top of the widget.

  • Q2 – Final Flow Rate (MMSCFD)
  • H2 – Final Compressor Head (ft lbf/lbm)
  • BHP2 – Final Shaft Horsepower(HP)

PLTB Compressors 2.4_Output Rev_090120.png

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