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Xls Fixed |verified| — Ejector Design Calculation

Steam surface condensers and vacuum systems rely heavily on ejectors (or thermocompressors) to maintain operational efficiency. When dealing with a , the design calculation becomes a precise balancing act between motive fluid pressure, suction requirements, and discharge back-pressure.

To build a robust calculation sheet, you must define the following input variables: A. Motive Fluid Properties Usually high-pressure steam or air. Temperature ( Tmcap T sub m ): Needed to determine specific volume. Flow Rate ( Wmcap W sub m ): The mass flow available to do the work. B. Suction Fluid Properties Suction Pressure ( Pscap P sub s ): The vacuum level you aim to maintain. Entrainment Ratio ( ): The ratio of suction gas to motive gas ( ). This is the most critical output of your calculation. C. Discharge Conditions Discharge Pressure ( Pdcap P sub d ): The pressure the ejector must overcome (back-pressure). 3. The Step-by-Step Calculation Process ejector design calculation xls fixed

Mastering Ejector Design: A Comprehensive Guide to Fixed-Geometry Calculations Steam surface condensers and vacuum systems rely heavily

Where velocity is converted back into pressure (static head) to reach the discharge requirement. Motive Fluid Properties Usually high-pressure steam or air

If your suction fluid contains air or CO2, the molecular weight changes, which drastically alters the entrainment ratio.

If you are building or using a "fixed" design XLS, ensure it includes:

) does not exceed the "critical discharge pressure." If it does, the shockwave will move back into the throat, and the ejector will stop suctioning (breaking the vacuum). 4. Structuring Your XLS for Accuracy