SURF design study workflow

neqsim surf-study turns a structured study specification (surf_study.v1) into a generated and solved NeqSim field network, a concept comparison, 15 A3 drawings, quantities and cost, and a 20-chapter report with a fail-closed validation report. The toolkit reuses FieldNetworkTopology over LoopedPipeNetwork, FieldWellNetworkCoupler, FieldWellNetworkProcessUnit, SubseaProductionSystem and SURFCostEstimator (see SURF network integration) and the shared report kit of the flow-assurance study report. It adds no solver.

The result is a screening-level deliverable. The software never assigns the REVIEWED label and never approves a design.

For generic single-phase Darcy edges, the canonical network uses the steady passive-edge balance $h_{out} + g z_{out} = h_{in} + g z_{in}$ before applying the configured lumped heat transfer. This keeps elevation work direction-aware for risers and descending injection lines. The workflow checks the resulting arrival temperature against an independent plug-flow calculation; Beggs-Brill and two-fluid edges retain their dedicated energy models.

Commands

neqsim surf-study --init study_inputs
neqsim surf-study study.yaml --out surf_report --strict
neqsim surf-study --demo --out demo --no-word
neqsim surf-study study.yaml --out surf_report --stage report --task my_task

Stages: build-model (validate, generate plans, builders and the mapping manifest), run (solve every concept and case, cached on the generated plan), report (dataset, drawings, document, validation) and all. Exit codes: 0 ok, 1 strict validation failure, 2 input or usage error.

Specification

import sys
sys.path.insert(0, "devtools")
import surf_spec
spec, findings, model = surf_spec.load_spec("devtools/surf_examples/four_well_tieback/study.yaml")
assert not [f for f in findings if f["level"] == "error"]
assert len(spec["concepts"]) >= 2

Units are in key suffixes (_barg is rejected; use absolute _bara). Missing, unavailable or non-finite values stop the run before anything is solved. The specification must contain at least two concepts, three cases, flexible-line supplier U-values and acceptance criteria with sources.

Output layout

study_inputs/, model/ (builders, topology JSON, mapping_manifest.json), cache/, dataset/, drawings/, figures/, handoff/ (HO-01 to HO-08), layout_spec.json, the DOCX/PDF report and validation_report.md.

Maturity

Numerical screening, supplier confirmation, specialist analysis, independent verification and approval are separate states. Severe slugging, pigging dynamics, dynamic riser response, fatigue, seabed structural response and manufacturer umbilical or flexible-pipe construction are hand-offs, not results. The riser sheet is a concept schematic, geometry not analysed.

Agent skill map, the surf-design-study agent and the skills neqsim-surf-design-study, neqsim-surf-model-generation and neqsim-surf-report-drawings.