Based on correlations for steam ejectors, the following equations are standard for design:
For a standard steam jet ejector, a common empirical correlation used in Excel-based models to find the Entrainment Ratio ( ejector design calculation xls fixed
The area ratio (R_a = Area of mixing throat / Area of nozzle throat) is the single most critical variable. A fixed XLS provides a based on discharge pressure, preventing the user from entering physically impossible values (e.g., R_a < 1.5 for sonic flow). Based on correlations for steam ejectors, the following
Must be higher than the discharge pressure. For weeks, the plant’s vacuum system had been
For weeks, the plant’s vacuum system had been underperforming. The steam ejector, meant to pull a vacuum on the main distillation column, was failing to reach its design critical back pressure. Elias had run every CFD simulation in the book, but the real-world results were stubbornly off by 15%.
To illustrate the ejector design calculation XLS fixed process, let's consider an example:
Calculated to ensure the primary gas reaches the necessary supersonic speeds for efficient operation. ScienceDirect.com Calculation Methodology Motive Nozzle Sizing: