Source S and Resistive-Source RS Power Calculation

Source S and Resistive-Source RS Power Calculation

Source submodels

Thermal source submodels have a source power variable and its associated energy variable:

To respect the sign convention, the dh variable is signed as oriented toward the exterior of the source component such that:

• if the source is giving energy to the rest of the system;

• if the source is receiving energy from the rest of the system.

Resistive-Source RS elements with thermal ports

The completion of the Bond Graph framework to address the Thermal port aspects requires some additional types of variables. These Resistive-SourceRS variables illustrate the amount of power transformed into heat but kept inside the system. These variables ensure consistency between a bond graph model and a non-bond graph model and also ensure a valid power balance.

The part of the resistive R power that is transmitted via the thermal port to other component parts of the system must be represented by a Resistive-Source RS power variable and a corresponding energy variable:

To respect the sign convention, the dh variable must be signed as oriented towards the exterior of the system, which is usually the case.

The corresponding energy is calculated as the integral value of this power.

It is worth mentioning that the RSpowers do not appear in the power balance. This is due to the fact that these powers are only transformed from a power type (mechanical, hydraulic, electrical) to heat that stays in the system. RS illustrates the amount of power/energy transformed into heat and kept in the Simcenter Amesim model (transferred to the heat port or kept inside the fluid).