Stream table and energy summary¶

After a solve, the stream table lists every stream of the flowsheet — temperature, pressure, molar and mass flows, composition, vapour fractions and, per phase, enthalpy, entropy and density — and the energy summary lists each unit's duty, work and energy balance and the flowsheet's overall balance. It is computed from the run's bundle each time it is asked for, with the property basis the run used, and is stored nowhere: it adds nothing to the run and changes none of its identities. All values are in SI units.

Getting it¶

Transport	Call
Python	`app.get_stream_table(job_id)` — a `Projection` whose `value` is the document
CLI	`openflowsheet streams --project <dir> --job <job_id> [--format text\\|json\\|csv] [--output FILE]`
CLI, a bundle directory	`openflowsheet streams <bundle dir>`
HTTP	`GET /v1/jobs/{job_id}/stream-table`
MCP	the tool `get_stream_table`

The job must have ended and written a replay bundle with a solution. A run that did not converge has no solution state, and the request is refused not_found, naming the files the bundle does hold and the run's outcome. A property basis that is not installed (CoolProp, for example) is refused unsupported with what to install.

A Rankine energy check in one call¶

Checking a cycle's energy balance used to take a property provider, an evaluation context and a phase chosen by hand for each stream. With the table it is one call:

from openflowsheet.application.local import LocalApplication

with LocalApplication.open("plant") as app:
    table = app.get_stream_table("job-000001").value

for stream in table["streams"]:
    mixed = stream["substreams"][0]
    print(stream["id"], stream["T"], stream["P"], mixed["vapor_fraction_molar"], mixed["H_flow"])

overall = table["energy"]["overall"]
print(overall["H_products"] - overall["H_feeds"], overall["Q"] + overall["W"], overall["closure"])
for unit in table["energy"]["units"]:
    print(unit["id"], unit["model"], unit["Q"], unit["W"], unit["closure"])

closure is (Q + W) − (H_out − H_in), the verifier's sign, with duty and work counted positive into the unit; next to it, each unit and the overall balance quote the certificate's own energy check, with its tolerance and result.

What the document holds¶

The document (stream-table-v1, schema stream-table.schema.json) has a header — the job, run, revision, the state and certificate it was computed from, verification_status, judged_at and the property basis with its reference convention — then components, streams and energy.

A stream has T, P, its two ends, dormant, the checks the certificate holds for it, and one substream (mixed in this version).
The substream has the flows n (mol/s) and m (kg/s) per component and in total, the mole and mass fractions x and w, the enthalpy, entropy and volume flows, h, s per mole and per kilogram, the density rho, the two vapour fractions, and its phases.
A phase is identified by its family (VAPOR, LIQUID) and carries its own amounts, fractions and properties, including the molar volume v.
The vapour fractions vapor_fraction_molar and vapor_fraction_mass are the vapour's share of the stream on a mole and on a mass basis; they are 0 or 1 for a single-phase stream. There is no member called "quality".
phase_source says where the phases came from: declared (the stream's declared phase), carried_split (the vapour and liquid the solution carries), carried_lifted_split (the vapour and liquid split the solution carries where the verifier could not recompute it by a flash: a stream at its boiling point, for example), flash (an equilibrium flash at the stored temperature and pressure) or zero_flow. A flashed stream close to a phase boundary has flash_near_phase_boundary true: there the solve's verifier may have decided the phases differently.

Enthalpy and entropy are on the basis's reference convention, named in every substream (convention); values from different bases are not comparable.

Absent values¶

A value that cannot be given is null, and its object's absent map says why, with a message code: a dormant stream has no temperature (zero_flow); a basis may not provide a property (property_not_provided, for example the density of the Wilson basis's ideal-gas vapour); a property call or a flash may fail (property_evaluation_failed, flash_failed); a value may not be finite (value_not_finite); an energy total needs every stream's enthalpy flow (stream_enthalpy_absent); and a unit model whose energy balance the certificate does not check has no balance (energy_balance_undefined). Each code is explained in Notices and Refusals, and by openflowsheet explain <code>. The text form shows an absent value as - with a footnote, the CSV form as an empty cell.

Reading it safely¶

The table describes the solution the run stored; it is not a verification. Read verification_status (and judged_at, the state the verifier judged) before relying on the numbers: the text form starts with a warning when the status is not VERIFIED.

Over HTTP and MCP the document arrives as a projection: the default depth (12) holds a whole stream, and pointer="/streams" with limit and cursor pages the streams of a large flowsheet. The CLI pages and assembles the document for you.