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Bevel-edged orifice in a transition section

Bevel-edged orifice in a transition section ψ l d 2 d 1 d o
Bevel-edged orifice in a transition section

Values for calculation

d_1 \mathrm{mm}
d_2 \mathrm{mm}
d_o \mathrm{mm}
ψ \mathrm{°}
l \mathrm{mm}

Calculation

Diameter ratio

β=\cfrac{d_o}{d_1}

β\le\cfrac{1}{1+2\cdot\cfrac{l}{d_o}\cdot\tan{ψ}}

Coefficient C_b

C_b=\left(1-\cfrac{ψ}{90}\right)\cdot\left(\cfrac{ψ}{90}\right)^{\cfrac{1}{2+l/d_o}}

Jet contraction ratio

λ=1+0.622\cdot\left[1-C_b\cdot\left(\cfrac{l}{d_o}\right)^{\cfrac{1-\sqrt[4]{l/d_o}}{2}}\right]\cdot\left(1-0.215\cdot β^2-0.785\cdot β^5\right)

Loss coefficient

ζ=0.0696\cdot\left(1-C_b\cdot\cfrac{l}{d_o}\right)\cdot\left(1+0.42\cdot\sqrt{\cfrac{l}{d_o}}\cdot β^2\right)\cdot\left(1-β^5\right)\cdot λ^2+\left(λ-\left(\cfrac{d_o}{d_2}\right)^2\right)^2

Discharge coefficient

μ=\cfrac{1}{\sqrt{ζ+1}}