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Impinging_Jets_ARNHex



Procedure Impinging_Jets_ARNHex(Fluid$, T, P, u, D, H, L : h_bar, Nusselt, Re) calculates the average heat transfer and Nusselt number for a hexagonal array of round nozzles with diameter D positioned perpendicular to a plate with its exit a distance H from the plate.  The nozzle centers are positioned a distance L apart  as shown in the figure.  

Inputs
Fluid$ is a string or string variable that can be any fluid in the EES data base.  The fluid can be an ideal gas, a real fluid, a brine, or an incompressible fluid in the Solid-Liquid_Props fluids library.  
T - the temperature of fluid exiting the jet  [C], [K], [F], or [R]
P -  pressure can be in [Pa], [kPa], [bar], [MPa], [atm] or [psia]    (Note that for brines, this parameter provides the concentration in % instead of pressure.)  
u  - the velocity of the flow exiting the nozzle [m/s] or [ft/min]
D -  the diameter of the nozzle in [m] or [ft]
H -  the distance between the nozzle exit and the surface that the jet impinging on in [m] or [ft]
L - the distance between nozzle centers in [m] or [ft]. 

Outputs
h_bar -  average heat transfer coefficient in [W/m^2-K] or [Btu/hr-ft^2-R]
Nusselt - average Nusselt number [-]
Re - Reynolds number [-]

Notes:
This procedure is responsible for determining the property data of the fluid specified and calculating the Reynold and Prandtl numbers. This procedure then passes dimensionless information to the non-dimensional procedure Impinging_Jets_ARNHex_ND. The non-dimensional procedure returns the values for  Nusselt njmber which is used to calculate the heat transfer coefficient.

Example
$UnitSystem SI C kPa J mass
$VarInfo h_bar units=W/m^2-K
Fluid$='air'
T=25 [C]
P=100 [kPa]
Vel=20 [m/s]
D=0.005 [m]
L=0.025 [m]
H=0.02 [m]
Call impinging_jet_arnhex(Fluid$, T, P, Vel, D, H, L:h_bar, Nusselt, Re)

{Solution: 
h_bar=168.4 [W/m^2-K]
Nusselt=33 
Re=6,320  
}

Impinging Jets Index