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<< Click to Display Table of Contents >> Mid-span calculation |
  
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<< Click to Display Table of Contents >> Mid-span calculation |
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Results of the mid-span calculation are given in Dimensions on the page Values in Flow properties and Velocity triangle for inlet and outlet. These calculation are based on the fluid properties and the following set of equations:
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Perfect gas |
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Continuity equation |
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Density in accordance to fluid model |
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Velocity |
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Total temperature in accordance to fluid model |
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State change in accordance to fluid model |
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In a cross section the boundary conditions are:
•Mass flow ,
•Cross section A,
•Total state (pt, Tt),
•Swirl (cu·r).
To calculate the remaining quantities (c, cm, ρ, p, T), the above given set of equations must be solved. There is a minimum cross section Amin at which a Ma-number of 1 is reached. Below Amin a physically reasonable state cannot be determined. In that case a warning is generated (see e.g. compressor).
In case of incompressible fluids the Bernoulli equation is used instead of state change formulas:
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