Pressure drop prediction models o Garimella et al

$Pressure drop prediction models o Garimella et al. (2005) Void fraction is calculated using$

Pressure drop prediction models o Garimella et al. (2005) Liquid and vapor friction factors:

Pressure drop prediction models o Garimella et al. (2005) Liquid superficial velocity is given

Pressure drop prediction models o Garimella et al. (2005) Interfacial friction factor: Laminar region:

Pressure drop prediction models o Garimella et al. (2005) The pressure gradient is determined

Heat transfer prediction models o Bandhauer et al. (2005) o Considered parameters o o

Heat transfer prediction models o Bandhauer et al. (2005) Interfacial shear stress: Friction velocity

Heat transfer prediction models o Bandhauer et al. (2005) Film thickness is directly calculated

Heat transfer prediction models o Bandhauer et al. (2005) Turbulent dimensionless temperature is given

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Pressure drop prediction models o Garimella et al. (2005) o Considered parameters o o Single-phase pressure gradients Martinelli parameter Surface tension parameter Fluid and geometric properties Heat and Mass Transfer Laboratory 1

$Pressure drop prediction models o Garimella et al. (2005) Void fraction is calculated using$

Pressure drop prediction models o Garimella et al. (2005) Void fraction is calculated using the Baroczy (1965) correlation: Liquid and vapor Re values are given by: Heat and Mass Transfer Laboratory 2

Pressure drop prediction models o Garimella et al. (2005) Liquid and vapor friction factors: Therefore, the single-phase pressure gradients are given and the Martinelli parameter is calculated: Heat and Mass Transfer Laboratory 3

Pressure drop prediction models o Garimella et al. (2005) Liquid superficial velocity is given by: This velocity is used to evaluate the surface tension parameter: Heat and Mass Transfer Laboratory 4

Pressure drop prediction models o Garimella et al. (2005) Interfacial friction factor: Laminar region: Turbulent region (Blasius): Heat and Mass Transfer Laboratory 5

Pressure drop prediction models o Garimella et al. (2005) The pressure gradient is determined as follows: Heat and Mass Transfer Laboratory 6

Heat transfer prediction models o Bandhauer et al. (2005) o Considered parameters o o o Pressure drop Dimensionless film thickness Turbulent dimensionless temperature Pr Fluid and geometric properties Range / applicability o 0. 4 < D < 4. 9 mm o R 134 a o 150 < G < 750 kg/m 2 s Heat and Mass Transfer Laboratory 7

Heat transfer prediction models o Bandhauer et al. (2005) Interfacial shear stress: Friction velocity is now calculated: Heat and Mass Transfer Laboratory 8

Heat transfer prediction models o Bandhauer et al. (2005) Film thickness is directly calculated from void fraction: This thickness is used to obtain the dimensionless film thickness: Heat and Mass Transfer Laboratory 9

Heat transfer prediction models o Bandhauer et al. (2005) Turbulent dimensionless temperature is given by: Therefore, the heat transfer coefficient is: Heat and Mass Transfer Laboratory 10