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h1. Linear Flow Orifice Meter Equations


h3. Total Flow Rate Through Weir

{latex} $$ Q = cC_o [h + {2 \over 3} s] $$ {latex}
The constant of proportionality, cCo :
{latex} $$ cC_o = C_d W k\sqrt{2 g s} = {s^Q_{1max} \over 2H_{dmax}} $$ {latex}
The variable k :


h3. Flow Through Rectangular Base of Weir

{latex} $$ kq_w = {2 C_d \sqrt{2g} $$ {latex}
*Combined and substitued* :
{latex} $$ Q = W 2over 3} W C_d \sqrt{2g} {s^{1[{{(h + s)}^{3 \over 2}} [h + - {h^{2 \over 3}} s] $$ {latex}

h3. Flow Through Rectangular Base of WeirWidth

{latex} $$ q_wW = {4Q_max \over 3} W {C_d \sqrt{2g} [{{(h + s)}^{2 {H_dmax^{3 \over 32}} - {h^{2 \over 3}}]\sqrt{3 g Pi_Sutro}} $$ {latex}


h3. Rectangular Base Height

{latex} $$ s = {3 \over 2} \Pi_{sutro}H_{dmax} $$ {latex}
{latex} $$ Pi_{sutro} = {Q_min \over Q_max =  {{2 \over 3}s} \over {H_dmax}$$ {latex}

Pi sutro is equal to 0.1 = Q

h3. Profile of Curved Portion

{latex} $$ y = {W \over 2} [1 - {s \over \Pi} tan^{-1} \sqrt{x \over s} ]$$ {latex}