Ejector Design Calculation Xls Fixed Site

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).

) will lead to 'choking' or 'backflow' in fixed-nozzle designs." Efficiency (

Here, the spreadsheet solves the normal shock wave equations. A fixed XLS uses pre-calculated gas dynamic functions (Prandtl-Meyer, Rayleigh flow) embedded as array formulas, not macros. This ensures that the shock location calculation does not crash when switching from subsonic to supersonic regimes. ejector design calculation xls fixed

An ejector uses a high-pressure motive fluid to entrain and compress a low-pressure suction fluid. The process relies entirely on the conversion of pressure energy into kinetic energy, and back into pressure energy.

: $$A_d = \frac\dotm_d R T_dP_d V_d$$ (Note: $T_d$ rises slightly due to compression). The area ratio (R_a = Area of mixing

When using a fixed Excel workbook for ejector calculations, minor structural errors can lead to major physical miscalculations. Keep an eye on these technical points:

The spreadsheet should automate the following steps using standard fluid mechanics (often based on the Heenan and Gilbert isentropic expansion Expansion Ratio ( Compression Ratio ( Entrainment Ratio ( This is the "heart" of the calculation. Text for XLS: A fixed XLS uses pre-calculated gas dynamic functions

Whether you are designing a steam ejector for a vacuum drier, a gas ejector for a flare gas recovery system, or a liquid ejector for a chemical reactor, demand a fixed spreadsheet. Look for no iterative loops, no hidden macros, and a validation sheet. In the words of senior process engineers: "A fixed ejector XLS is worth a thousand simulations."

) cell into your inputs. Multiply the specific gas constant ( across your velocity and area formulas. B. Resolving Circular References in the Mixing Zone

For a standard steam jet ejector, a common empirical correlation used in Excel-based models to find the Entrainment Ratio (

Calculate the overall adiabatic efficiency to validate the design. 4. Results Summary Table Motive Nozzle Diameter cap D sub n Mixing Tube Diameter cap D sub m Diffuser Exit Diameter cap D sub e Actual Entrainment Ratio 5. Troubleshooting & "Fixed" Design Checks Add a "Validation" column using statements in Excel: ? (Required for operation) Is the Mach number at the nozzle exit is greater than 1.0 ? (Ensures supersonic flow for high-pressure recovery) "Fixed Geometry Status": [Stable / Critical / Unstable] for the entrainment ratio calculation?