The SCUFL2 language is the abstract set of constructs that define a Taverna workflow.
This has been formalized in an OWL ontology,
which is used by the scufl2-rdfxml module of the SCUFL2 API
to serialise the Taverna workflow bundle.
At the core of this is a workflow bundle, which combines a set of workflows and profiles.
You can browse a serialisation of using the SCUFL2 ontology within a Taverna workflow bundle in this example.