# Responses

## Introduction

In the data tree of Flux the node Solver > Optimization > Responses allows the user to define physical quantity that will be optimized during the optimization process engaged by Flux. The short list of the responses is given below:
Table 1. Table summarizing all the responses available in Flux
Physical quantity to optimize Formula Computation entity Unit
Torque on a mechanical set (virtual works)
• dWm: variation of the magnetic energy
• dθ: virtual displacement of the nodes around an axis
On a mechanical set N.m
Torque ripple on a mechanical set (virtual works)
• Tmax: Maximum value of the torque
• Tmin: Minimum value of the torque
• Tmean: Mean value of the torque
On a mechanical set %
Mechanical response - Compliance
• u: applied displacements
• f : applied forces (centrifugal load in our case)
On the faces defined in the mechanical problem J
Mechanical response - Von Mises Stress Maximal admissible stress limit obtained from a 3x3 tensor of mechanical stresses On the faces defined in the mechanical problem MPa = N.mm-2
Equation response User-defined equation using one or more responses Depending on the given responses Depending on the given responses
Super response The selected predefined function applied to the response(s) Depending on the given responses Depending on the given responses
Force on a face region (virtual works)
• dWm: variation of the magnetic energy
• dx: virtual displacement of the nodes along an axis
On a face region N
Sum of the fluxes of selected coils
• n : Number of selected coils
• L : Depth of the domain
• Nsi : Winding function of the associated coil
• Az : Magnetic vector potential in Z direction
On one or several coil conductor components Wb
Flux flowing through lines
• L : Depth of the domain
• Az : Magnetic vector potential in Z direction
• n1 and n2 the end nodes of the line where the flux is computed
On a line Wb
Volume of 2D faces On faces mm3
Force computed on a path (Maxwell tensor)
• L : Depth of the domain
• Bn : Normal magnetic flux density
• Bt : Tangential magnetic flux density
• µ0 : Air magnetic permeability
Based on the Maxwell tensors approach, this method requires a path in a front of a piece of iron (plunger for an actuator, stator tooth ...)
Attention: This method is valuable only along a path in a air or vaccum region.
N