P O I N T H E A T S O U R C E

Enter the quantity Qp in unit power (SI unit: W). Positive Qp is heating while a negative Qp is cooling.

Convective Cooling

The Convective Cooling node adds the following heat flux contribution to its

boundaries:

h Text – T

B O U N D A R Y S E L E C T I O N

From the Selection list, choose the boundaries to add a convective cooling contribution. For information about selecting boundaries.

H E A T F L U X

Select a Heat transfer coefficient h (SI unit: W/m2K) to control the type of convective cooling to model—User defined (the default), External natural convection, Internal natural convection, External forced convection, or Internal forced convection. If convective flux is required on the downside, use the default, which sets h 0.

•For all of the options, enter an External temperature, Text (SI unit: K).

•For all of the options (except User defined), follow the individual instructions below and select an External fluid—Air, Transformer oil, or water. If Air is selected, also enter an Absolute pressure, pA (SI unit: Pa). The default is 1 atm.

External Natural Convection

Select Vertical wall or Horizontal plate from the list.

•If Vertical wall is selected, enter a Wall height L (SI unit: m).

•If Horizontal plate is selected, define the Plate diameter (area/perimeter) L (SI unit: m). L is approximated by the ratio between the surface area and its perimeter.

The defaults are 0.

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Internal Natural Convection

Select Narrow chimney, parallel plates or Narrow chimney, circular tubes from the list.

•If Narrow chimney, parallel plates is selected, enter a Plate distance L (SI unit: m) and a Chimney height H (SI unit: m). The defaults are 0.

•If Narrow chimney, circular tubes is selected, enter a Tube diameter D (SI unit: m) and a Chimney height H (SI unit: m). The defaults are 0.

External Forced Convection

Select Plate, averaged transfer coefficient or Plate, local transfer coefficient from the list.

•If Plate, averaged transfer coefficient is selected, enter a Plate length L (SI unit: m) and a Velocity, external fluid Uext (SI unit: m/s). The defaults are 0.

•If Plate, local transfer coefficient is selected, enter a Position along the plate xpl

(SI unit: m) and a Velocity, external fluid Uext (SI unit: m/s). The defaults are 0.

Internal Forced Convection

The only option is Isothermal tube. Enter a Tube diameter D (SI unit: m) and a Velocity, external fluid Uext (SI unit: m/s). The defaults are 0.

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