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DuctGradualContraction_CL

Returns the pressure drop associated with a gradual contraction given the fluid, its flow rate and state, the upstream and downstream diameters, and the half angle.  Valid for circular duct cross-sections.  This function calls the K_gradual_contraction function from the minor loss library.

DELTAP = DuctGradualContraction_CL(F$, m_dot, T, P, D_1, D_2, theta)

Inputs:

F$:  fluid string identifier

m_dot:  mass flow rate (kg/s, lbm/hr)

T:  inlet temperature (K, C, F, or R)

P:  inlet pressure (bar, atm, Pa, kPa, or MPa)

D_1:  upstream duct diameter (m or ft)

D_2:  downstream duct diameter (m or ft)

theta:  half angle (radian or degree)

Output:

DELTAP:  pressure drop (bar, atm, Pa kPa, or MPa)

Example: 

$UnitSystem SI Mass J K Pa Degree

$Load Component Library

$VarInfo DP units=Pa

m_dot = 0.2 [kg/s]

T = 300 [K]

P = 100e3 [Pa]

D_1 = 0.15 [m]

D_2 = 0.1 [m]

theta = 20 [degree]

F$ = 'Air'

DP = DuctGradualContraction_CL(F$, m_dot, T, P, D_1, D_2, theta)

{Solution:

DP = 21.55 [Pa]}