: Calculate the ejector's performance parameters, including efficiency, using the entrainment ratio, compression ratio, and other design conditions.
Calculate the velocity of the motive fluid as it exits the nozzle.
[Inputs: Pm, Ps, Pd, Ws] │ ▼ [XLS Fixed Calculations: Mach Numbers -> Throat Areas -> Diffuser Angles] │ ▼ [Outputs: Mm (Motive Consumption), D_throat, D_diffuser]
= (B6 / B4) * SQRT((B11 * B5) / (B10 * B12 * (2 / (B10 + 1)) ^ ((B10 + 1) / (B10 - 1)))) Nozzle Throat Diameter ( Dtcap D sub t = SQRT((4 * B22) / PI()) * 1000
In the world of fluid dynamics and process engineering, the ejector (or jet pump) remains one of the most elegant yet misunderstood pieces of equipment. With no moving parts, it uses the Venturi effect to convert pressure energy into velocity, suctioning a secondary fluid. However, designing an ejector is notoriously complex. The interplay between motive pressure, suction pressure, discharge pressure, and gas/vapor molecular weights requires iterative solving of conservation equations. ejector design calculation xls fixed
=(B7-B4)/(B1-B7) (Discharge - Suction) / (Motive - Discharge) Velocity of Sound ( ): =SQRT(GAMMA * (8314 / MW) * (T_m + 273.15)) Nozzle Area ( Atcap A sub t
Download a trial of a fixed ejector calculation template (PDF preview available) and input your operating conditions. Verify that the entrainment ratio matches your existing ejector performance curve. If it does, you have found your permanent design tool.
If your spreadsheet assumes supersonic flow when the pressure profile is actually sub-critical (subsonic), the geometric output will be fundamentally flawed. For steam, changes based on whether it is superheated ( ≈1.3is approximately equal to 1.3 ) or saturated/wet ( ≈1.13is approximately equal to 1.13 ). Do not use a fixed value (which is for air) across all calculations. 5. Summary Check for Validating Your Spreadsheet
To simplify the ejector design calculation process, an Excel spreadsheet can be used to perform the necessary calculations. A fixed Excel template, often referred to as an "xls fixed" file, can be used as a starting point. With no moving parts, it uses the Venturi
This is why the search for an is one of the most common queries on engineering forums. Engineers are tired of floating macros, broken iterative loops, and unprotected cells. They want a fixed —meaning stable, validated, and non-crashing—spreadsheet.
Accessible to engineers in standard design environments.
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): Find the area required to pass the motive steam at sonic speed (choked flow): your will remain an accurate
An Excel-based ejector design calculation can be a useful tool for engineers and designers to quickly evaluate and optimize ejector performance. A fixed Excel template, or "xls fixed" file, can serve as a starting point for these calculations. By including the necessary formulas and calculations, an Excel template can help ensure accurate and efficient ejector design.
By maintaining strict input validation ( Data Validation rules in Excel) and locking the structural calculation cells ( Review > Protect Sheet ), your will remain an accurate, highly repeatable asset for process engineering teams. Next Steps for Implementation
Set up these cells as your input fields (User enters data here).
