Ejector Design Calculation Xls [exclusive] -

This allows you to required nozzle area if $W_m$ is given. Step 3: Momentum Balance in the Mixing Section (Most Critical) This is where spreadsheets shine. Assuming constant-area mixing (most common model), apply conservation of momentum:

Then, using continuity: $$W_m = \rho_m \cdot A_n \cdot V_m$$

$$P_{discharge} = P_{throat} + \eta_d \cdot \frac{1}{2} \rho_m (V_2^2)$$ ejector design calculation xls

However, designing an ejector is not simple. The interplay of supersonic shock diamonds, boundary layer separation, and entrainment ratios requires iterative, complex thermodynamics. For decades, engineers relied on slide rules and nomographs. Today, the standard tool for rapid, reliable design is the .

Whether you are designing a vacuum ejector for a petroleum column or an eductor for a chemical reactor, master the spreadsheet. Understand every cell. Validate against real data. Then, and only then, will you truly understand the elegant physics of the motionless pump. Download this article as a PDF, open a blank Excel workbook, and begin coding the momentum balance in Section 3. Your first working ejector XLS will be the most enlightening spreadsheet you have ever built. This allows you to required nozzle area if $W_m$ is given

A simplified practical approach used in industry XLS templates: Use the by El-Dessouky (2002) for steam-jet ejectors: $$Er = 0.85 \times \left( \frac{P_m}{P_s} \right)^{0.77} \times \left( \frac{P_d}{P_s} \right)^{-1.13}$$

$$(W_m + W_s) \cdot V_2 = W_m \cdot V_m + P_s \cdot A_t - P_2 \cdot A_t$$ The interplay of supersonic shock diamonds, boundary layer

While empirical, this is highly reliable for preliminary sizing and is easily embedded in XLS. The diffuser converts velocity head back to pressure. Efficiency ($\eta_d$) typically 70-85%: