Radiation - Inputs

1. Overview

This panel allows describing the parameters defining the radiation phenomenon existing in the machine.

Mainly, two radiation phenomena exist in the machine:

  • From the end windings, rotor and stator ends to the frame and the end caps.
  • Between the rotor and the stator, in the airgap.
Internal cooling - Radiation design area
1 Display the axial and radial view of the machine.
2 Display the internal cooling datasheet, showing the thermal parameters defining the internal heat exchanges.
3 Radial view of the motor, where specific exchange areas can be highlighted depending on the selected input.
4 Axial view of the motor, where specific exchange areas can be highlighted depending on the selected input.
5 The section “Radiation” is selected.
6 Button to set the internal emissivity automatically by internal process
7 Selected button, to set the internal emissivities manually
8

Input related to the radiation corresponding to the selected radiation mode. In user mode, the following emissivities must be set:

  • The frame inner surface emissivity, with a default value of 0.8

  • The rotor and stator emissivity, with a default value of 0.3

    These emissivities are used for the radiation occurring in the airgap, and from the rotor end and stator end to each end space.

  • The end winding emissivity, with a default value of 0.4.This emissivity is applied to non-potted end-windings only. The assumption is made that the potted end-windings do not radiate any power.
9 Button to restore default input values.
10 Button to apply inputs. Pressing the enter key twice applies inputs too.
11 Icon to export internal cooling data into *.txt or *.xlsx files.

2. Interface – Inputs

This panel allows describing imperfect contacts between the different components of the machine.

The imperfect contacts are here modeled as a parasitic airgap between two parts, through which the heat must be conducted through to go from one part to the other.

The interface gaps are composed of air at the atmospheric pressure, at 20 °C, equivalent to 293.15K. For more information on material properties, please refer to the material database (“Materials application”).

Mainly, the imperfect contacts existing in a machine are:

  • Each interface/mounting of a laminated part on a solid material
    • Between the magnetic circuit and the frame
    • Between the magnetic circuit and the shaft
  • The imperfect contact between the magnetic circuit and the liner surrounding the slot.
  • The bearings. A single interface gap thickness is used to compute the total thermal resistance of the bearings. This single value of contact thickness is used in computations for both Connection Side bearing and Opposite Connection Side bearing.
Internal cooling - Interface design area
1 Display the axial and radial view of the machine.
2 Display the internal cooling datasheet, showing the thermal parameters defining the internal heat exchanges.
3 Radial view of the motor, where specific exchange areas can be highlighted depending on the selected input.
4 Axial view of the motor, where specific exchange areas can be highlighted depending on the selected input.
5 The section “Interface” is selected.
6 Button to set the interface gaps automatically by internal process.
7 Selected button, to set user interface gaps.
8 Parasitic interface thicknesses corresponding to the selected interface mode. In user mode, the following thicknesses must be set:
  • Magnetic circuit – frame interface thickness, with a default value of 30 micrometers.

  • Magnetic circuit – slot interface thickness, with a default value of 100 micrometers

    This corresponds to the imperfect contact between the liner and the iron core.

  • Magnetic circuit – shaft interface thickness, with a default value of 15 micrometers.
  • Bearings equivalent interface thickness, with a default value of 15 micrometers.
9 Button to restore default input values.
10 Button to apply inputs. Pressing the enter key twice applies inputs too.
11 Icon to export internal cooling data into *.txt or *.xlsx files.