Internal cooling outputs

1. End-space

Three plots exist for each end space, showing the convection coefficients and resistances in the end space, and the radiation resistances through the end space. The result structure is the same for Connection Side and Opposite Connection Side.

1.1 End-space convection (Coefficient and resistance)

These curves show the convection coefficients and resistances existing for each component having an exchange surface with the considered end space:

  • The frame inner surface (including the surfaces of the end cap and of the straight extension of the frame)
  • The stator and rotor ends
  • The end winding
  • The shaft

The curves are plotted for a range of rotor speed going from zero to the maximum speed set by the user in the X-Factor settings of COOLING subset, INTERNAL panel, and for the temperature of the internal fluid specified in the X-Factor settings.

1.2 End space radiation

These curves show the radiation resistances existing in the considered end space:

  • From the end winding to the frame. This resistance exists only when the end winding is not potted on the considered side.
  • From the rotor end to the frame.

No radiation resistance is considered from the stator ends to the frame, the end winding blocking the radiations between both surfaces.

These curves are plotted for active part temperatures going from the internal fluid temperature set by the user in X-Factor subset of COOLING subset, INTERNAL panel, to 150 Kelvin above this reference temperature.

2. Airgap

2.1 Airgap convection (Coefficient and resistance)

These curves give an overview of the total convection resistances existing when summing all exchange areas on the borders on the rotor side, and on the stator side. Two curves exist, showing the total convection resistance from the stator border and the airgap fluid, and from the rotor border to the airgap fluid.

The curves are plotted for a range of rotor speed going from zero to the maximum speed set by the user in the X-Factor settings of COOLING subset, INTERNAL panel, and for the temperature of the internal fluid specified in the X-Factor settings.

2.2 Airgap radiation

This curve shows an estimation of the overall radiation resistance between the stator and the rotor. To plot this curve, one of the borders is considered at the temperature of the internal fluid specified in the X-Factor settings, and the temperature of the hottest border take a range of temperature value from this reference temperature until 150 Kelvin above it.

3. Interface conduction resistances

This table shows the thermal resistances equivalent to the interface thicknesses set in the Interface settings.

Note: The resistances computed here do not consider the conduction through the material around the gaps. For instance, the resistance « magnetic circuit-frame » computed here does not take into account the conduction through the stator magnetic circuit or through the frame, but only the thermal resistance corresponding to the conduction through the parasitic thickness of air contained between the magnetic circuit and the frame.

4. Slot model characteristic

This table reminds to the user the slot fill factors and the thermal conductivities of the material composing the winding and the insulation, and then shows the equivalent axial and radial thermal conductivities of the slot.

The shown conductivities depend on the input mode selected by the user in Slot model settings.

In automatic mode, it is the conductivities computed by the FluxMotor model.

In user mode, these are the conductivities set manually by the user.

The thermal resistance between the in-slot winding and each of the end windings is computed at the end of the table, based on the slot axial equivalent conductivity.