The Simulation Mapper Class maps the Features in the FeatureFile to arguments required as simulation inputs in the OpenStudio workflow files (OSW).
Recall that a Feature refers to a single object in a district energy analysis, such as a building, district system, or transformer. The FeatureFile includes all data for all Features and could be written by a third party application or user interface; for our example we use the
GeoJSON format. The input GeoJSON file must be valid and must meet the additional requirements for data supported or required by the appropriate URBANopt™ GeoJSON Gem sub-schema. The Simulation Mapper only supports mapping the Building feature_type and has the capability to support mapping the following building types from the building_properties schema in the GeoJSON Gem:
- Office
- Outpatient health care
- Inpatient health care
- Lodging
- Food service
- Strip shopping mall
- Retail other than mall
- Education
- Nursing
- Mixed use*
*Note - The Mixed use building type can accommodate up to 4 building types and their corresponding fractions of total floor area. If the number of building types is fewer than 4, additional building use types must be added but the fraction of total area can be entered as 0.
Within the Mapper Classes, functionality can be added to apply measures based on the Feature properties. For example, Measures can be implemented only for a certain building type, or can be implemented only if the number of floors is greater than a particular number, etc.
The URBANopt GeoJSON Example Project includes a default Simulation Mapper Class to translate an URBANopt GeoJSON Feature to an OpenStudio Model. The HighEfficiency mapper class inherits from the BaselineMapper class and can override measures that were skipped in the BaselineMapper.
When the Scenario is run, a new Simulation Mapper instance is created and the create_osw method is implemented for each Feature assigned to the Simulation Mapper Class in the Scenario CSV.
The default Simulation Mapper Class can be used directly, extended, or modified. Alternatively, a completely different Simulation Mapper Class can be created.
In case the user wants to use an existing OpenStudio Model of a Feature in the simulation, the name of the OpenStudio model should be added in the detailed_model_filename property of the Building Feature in the Feature File. The OpenStudio model should be added to the detailed_osms folder in the project directory.This OpenStudio model is loaded as a seed model for the Feature during simulation and measures such as create_typical_building_from_model and urban_geometry_creation are skipped for the Feature.
Alternatively, the absolute path of the OpenStudio Model can be added to the detailed_model_filename property of the Building Feature in the Feature File.
The user can choose to use OpenStudio Models for some Features and the urban_geometry_creation for other Features. In this case, Features with OpenStudio Models should include the id , name, detailed_model_filename and number_of_stories properties in the FeatureFile.