SME
Fluid Mechanics · Problem type
Which number must the model match?
Use this for “A model of a spillway is tested in a lab. Should it match the Reynolds, Froude, Mach or Weber number?”
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Which dimensionless number must a model of each flow match?
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Ask which force, besides inertia, shapes the flow.
Assumptions
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Match the number of the force that rules the flow, alongside inertia.
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Reynolds VL ÷ ν: viscosity. Froude V ÷ √(gL): gravity at a free surface.
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Mach V ÷ c: compressibility. Weber ρV²L ÷ σ: surface tension.
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Related lessons
Dimensional analysis
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