Source: https://guthlabs.ai/docs/instruments/stagnation-properties-calculator-compressible-flow/implementation/

instrument implementation / implementation-contract

# Stagnation Properties Calculator (Compressible Flow) implementation

A source-bound implementation contract for Stagnation Properties Calculator (Compressible Flow); deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t5-066

**Effect**: Computation or source lookup only

## Input and validation requirements

The stated pressure formula is undefined at γ=1 because the denominator γ−1 vanishes. The calculator needs explicit validation and rejection for this input.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "static_temperature_K": 288.15,
    "static_pressure_Pa": 101325,
    "mach_number": 0.8,
    "gamma": 1.4
  },
  "expected_outputs": {
    "stagnation_temperature_K": 325.0332,
    "stagnation_pressure_Pa": 154453.75
  },
  "working": "T0/T = 1 + ((1.4−1)/2)(0.8)^2 = 1 + 0.2×0.64 = 1.128. T0 = 288.15×1.128 = 325.0332 K. P0/P = 1.128^(1.4/(1.4−1)) = 1.128^3.5 ≈ 1.524340. P0 = 101325×1.524340 ≈ 154453.75 Pa."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/stagnation-properties-calculator-compressible-flow/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/stagnation-properties-calculator-compressible-flow/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/stagnation-properties-calculator-compressible-flow/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`