New calculation strategy with routing between individual systems
New calculation strategy with routing between individual systems
Description
Changes the calculation strategy in systems_design. So far, the power requirements of systems have all been added to one vector to then calculate the required source power. This works for conventional power supply (shaft power and bleed air from an engine and APU), but not for new technologies like a fuel cell APU. The new methodology adds input and output ports to each system and connects these. This way, power is actually routed between systems, leading to a more precise and flexible representation of the aircraft system architecture. The new methodology also enables accounting for the power/fuel requirement of an APU, which becomes relevant when it is used as a power source during the mission (e.g., fuel cell, batteries). The system architecture definition in the config file is also updated to allow for the routing between systems. Also, this simplifies the architecture definition for the user.
The new methodology has been tested for the standard and virtual strategy. In the standard strategy, the total system mass changes in the order of magnitude of 10^-3 due to small changes in the power conducted by the electric and hydraulic systems. These are less than 1 W and result from the slightly different calculation steps and resulting rounding.
A significant change can be seen in the shaft power required by the engine. It is lower with the new calculation methodology. In the old methodology power required by both hydraulic pumps was considered when calculating the required shaft power from the engine, even though only one of them is powered by shaft power, the other by electric power. Thus, the power requirement of the electric-driven pump is considered through the electric system and should not be accounted for a second time.
Related Issue(s)
- N/A
Screenshots/Logs
Comparison of acxml (left new, right old)
Changes in system mass:
Changes of shaft power required:
Testing Instructions
- Build systems_design
- Test the standard and virtual strategy with an aircraft from the aircraft references
- Compare the results to old systems_design methodology results
Example config file for virtual strategy: systems_design_conf_virtual.xml
I've tested with the current status of BWB, tandem wing, and strut braced wing and they all worked with both standard and virtual strategy.
Developer Checklist
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Code has been tested locally and/or in pipeline. -
(if applicable) documentation updated see unicado.gitlab.io!90 -
(if applicable) impact of new dependencies reviewed and included in project. -
Merge conflicts resolved with the target branch.
Additional Notes
While this MR is still a draft I am:
-
checking that shaft power should actually be lower -
removing unused debug statements -
testing that tandem wing, strut braced wing, and BWB also work