: The combined mixture enters a diffuser, where its velocity energy is converted back into pressure energy, allowing it to discharge against a predetermined back pressure. 2. Critical Design Parameters
The most critical dimensionless number in ejector design is the Area Ratio ($AR$). $$ AR = \frac\textArea of Mixing Throat\textArea of Nozzle Exit $$ This ratio dictates the operating curve of the ejector. ejector design calculation xls fixed
where P_d is the discharge pressure and P_s is the suction pressure. : The combined mixture enters a diffuser, where
Many simple spreadsheets assume a constant mixing efficiency (e.g., 0.8 or 80%). In reality, efficiency varies with flow rates. A "Fixed" efficiency input allows the engineer to tune the spreadsheet based on historical vendor data, making the tool more accurate for future predictions. $$ AR = \frac\textArea of Mixing Throat\textArea of
Create a table that shows how the suction vacuum changes if the motive steam pressure drops by 10%. 5. Common Pitfalls in Fixed Ejector Design
Use a lookup table for Steam Properties (IAPWS-IF97) to automate enthalpy and entropy shifts. Step 2: Mixing Zone Analysis