Verified calculation capability

Composite wall Calculation Capability

Plane composite wall from a layer list. R_i = L_i/(k_i A), optional films 1/(h A), R = R_in + ΣR_i + R_out. Optional Q=ΔT/R. Not Fourier/Newton Q, not lumped R-network, not heatsink θ, not steam, not cylindrical. · Physics · Thermo

Capability ID physics.thermo.composite_wall · version 1.0.0

Open calculator REST API MCP Evidence Evidence JSON Review policy

Model

Layer

Layer: R_i = L_i / (k_i A)
Film: R = 1 / (h A)
Wall: R = R_in + Σ R_i + R_out
Heat rate: Q = ΔT / R

Solve modes: plane

Inputs / Outputs

Canonical symbols for this capability. Agent schemas remain the contract.

Symbol	Quantity	Unit	Role
`A`	Shared face area in m².	—	input / output
`k1`	Layer 1 conductivity in W/(m·K). Alternative: layers[].	—	input
`L1`	Layer 1 thickness in m.	—	input
`k2`	Layer 2 conductivity in W/(m·K).	—	input
`L2`	Layer 2 thickness in m.	—	input
`layers`	Layer list {k, L}. Alternative: k1/L1…. Do not send both.	—	input / output
`h_in`	Optional inner film coefficient in W/(m²·K).	—	input / output
`h_out`	Optional outer film coefficient in W/(m²·K).	—	input / output
`dT`	Optional temperature difference in K. If given, Q=ΔT/R.	—	input / output
`R`	—	—	output
`Q`	—	—	output
`n`	amount of substance	—	output
`R_in`	—	—	output
`R_out`	—	—	output
`model`	—	—	output

Assumptions / Validity

Declared scope for this capability. Do not use it outside this domain.

Assumptions

Plane composite wall; 1-D; shared A; R_i = L_i/(k_i A)
Optional films R = 1/(h A); series only; Q=ΔT/R
Not Fourier/Newton Q pages
Not lumped R-network, not heatsink θ, not steam, not cylindrical

Not supported

Fourier/Newton Q as the primary product
lumped R-network of already-computed R
heatsink θJC/θSA
steam
cylindrical/spherical walls
radiation
transient Zth
CFD

Example

One numerical check. The calculator page holds worked steps and FAQ.

k1=1 L1=0.5 k2=0.5 L2=0.2 A=2 → R=0.45 K/W

Open this example in the calculator

Trust

Review-policy: engine tested — automated tests, sources, version lock, and evidence published. Supplemental to CVP; not Domain Expert Review. See CVP and Review policy.

Tier: Engine tested — catalog token engine_tested
Calculation version: 1.0.0
Evidence tests: 14/14 calculation tests · golden 1/1 · boundary 8/8 · property 5/5
Engine tested: Yes
Source checked: Yes
Supplemental domain review: Not performed
Named expert review: Not performed
Version lock: Supported (409 VERSION_MISMATCH)
Artifact consistency: Build verified · 1.0.0 (workspace artifacts agree)

Production attestation: Embedded snapshot: STALE · Last attested schema matched 1.0.0 snapshot / local build · Semantic contract ✓ · Last attestation PASS · current evidence changed · re-attestation required · Public/cache ✓ · Origin ✓ · Live production status PASS (0 stale; 163 CURRENT) @ 2026-09-17T03:09:03.307Z
Semantic contract: PASS
Evidence attested at: 2026-09-17T03:09:02.494Z
Last production check: 2026-09-17T03:09:02.494Z
Public / cache: PASS
Origin: PASS

Call this capability

Human page, REST, and MCP share the same engine and calculation_version. Build verified hashes workspace artifacts only. After deploy, attest:production GETs canonical URLs twice — the public/cached view an Agent actually hits, and origin — including every /capabilities/{id} HTML page. Public Capability HTML version must match catalog before production attestation passes. Live Trust rows above fetch /.well-known/calculatorx-production-attestation.json and the output schema const. Build hashes: release integrity. That proves currently published page / engine / schema / evidence / MCP agree — not that a historical version is independently immutable. Reference Calculation Standard — Production surface contract 4/4.

Tool id: composite-wall
Engine: composite-wall
REST: POST /api/v1/calc/composite-wall
MCP: execute_calculation with capability_id: "physics.thermo.composite_wall"
Agent input schema: Canonical (MCP / Agent)
Output schema: JSON Schema (latest)
Versioned input schema: Immutable pin (1.0.0)
Versioned output schema: Immutable pin (1.0.0)

References

Human-readable sources plus CVP reference evidence classes.

Sources

Incropera, F.P. and DeWitt, D.P. Fundamentals of Heat and Mass Transfer — Composite walls
ISO 80000-5 — Thermodynamics — Heat rate and temperature difference

Try with an agent

Inspect this capability via same-origin MCP, then call execute_calculation.

curl -sS -X POST 'https://www.calculatorx.com/mcp' \
  -H 'Content-Type: application/json' \
  -H 'MCP-Protocol-Version: 2026-07-28' \
  -H 'Mcp-Method: tools/call' \
  -H 'Mcp-Name: inspect_capability' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"inspect_capability","arguments":{"capability_id":"physics.thermo.composite_wall"}}}'

Inspect the trust tier and required assurance level before execution. Pin calculation_version (1.0.0) when reproducibility matters. Full protocol notes: MCP docs.