CST2013: Thermal Transient Result Overview

The transient solver creates many 1D results and the start solution result automatically after the simulation process was finished. To get time-dependent temperature- or heat flow density-fields it is necessary to define field monitors before the solver is started.

1D Results

Convergence

The convergence curve shows the residual of the linear or nonlinear solver versus iteration step for the computation of the start solution. The gradient of the curve indicates if the linear equation system is well conditioned or not. This curve is created automatically.

Timescale

This curve shows the current time for a given iteration step number. Integrating the "Timesteps" curve delivers the "Timescale" curve. This curve is created automatically.

Timesteps

This plot shows the time-step size versus the step number of the integration scheme. If the time step is small rapid transient changes are probably taking place - for instant if a source is steep ramped up with a time signal. This curve is created automatically.

Energy

During the simulation process the thermal energy inside all regions with a finite heat capacity is integrated and recorded.

with:

E(t): time dependent energy

T(t): time dependent temperature

Cp: heat capacity

rho: density

dV: volume element

This curve is created automatically.

Power

This curve shows the total amount of power entering all regions with a finite heat capacity.

with:

Pstored: Power stored in the structure

Ploss: Power added  by external loss distributions

Pcond: Power lost by thermal conduction to PTC regions. If power is added through PTC regions this is a negative value.

Prad: Power lost by radiation

Pconv: Power lost by convection

The power-curve is the derivative of the energy-curve with respect to the time. This curve is created automatically.

Temperature0D

This folder stores all temperature curves vs. time on points previously defined with the Monitor at Point tool.

Heatflow

The Heatflow folder contains the heatflow curves vs. time for all temperature and heat sources on PTC objects. These curves are created automatically.

Temperature

The Temperature folder contains the temperature curves vs. time for all temperature and heat sources on PTC objects. These curves are created automatically.

2D/3D results

Temperature

The transient temperature distribution is a scalar 3D field which is recorded at times previously defined with a 3D Field Monitor. It can be evaluated also on a 2D cut-plane.

Heat Flow Density

The stationary heat flow is a 3D vector field, which is recorded at times previously defined with a 3D Field Monitor. This field type shows were heat is transferred inside a structure, it can be evaluated also on a 2D cut-plane.