About the author: This guide was compiled using ASME PTC 37, ESDU Data Item 86030, and 12 years of process engineering experience with fixed-format calculation sheets.
A higher compression ratio requires a tighter mixing throat to prevent backflow or "break" conditions, where the ejector fails to maintain vacuum.
)—is already set, meaning performance is dictated by varying inlet fluid conditions and discharge pressure. DSpace@MIT Key Calculation Principles Entrainment Ratio ( This is the ratio of mass flow rate of entrained vapor ( ) to motive steam ( Choked Flow: When the compression ratio is is greater than 1.8 ejector design calculation xls fixed
When using a calculation spreadsheet or manual method, the following parameters are critical: Entrainment Ratio ( The ratio of the mass flow rate of the secondary fluid ( ) to the mass flow rate of the primary fluid ( Compression Ratio ( cap C cap R The ratio of discharge pressure to suction pressure. Area Ratio ( cap A cap R
To illustrate the ejector design calculation XLS fixed process, let's consider an example: About the author: This guide was compiled using
Implement an open-source IAPWS-IF97 steam table add-in for Excel. Replace static
Converts high-pressure energy into high-velocity kinetic energy. ESDU Data Item 86030
At=mmCd⋅γ⋅ρm⋅Pm⋅(2γ+1)γ+1γ−1cap A sub t equals the fraction with numerator m sub m and denominator cap C sub d center dot the square root of gamma center dot rho sub m center dot cap P sub m center dot open paren the fraction with numerator 2 and denominator gamma plus 1 end-fraction close paren raised to the the fraction with numerator gamma plus 1 and denominator gamma minus 1 end-fraction power end-root end-fraction Cdcap C sub d = Discharge coefficient (typically 0.95 - 0.98) = Specific heat ratio ρmrho sub m = Motive fluid density Pmcap P sub m = Motive fluid pressure 3. Step-by-Step .xls Sheet Architecture