Source: https://guthlabs.ai/docs/instruments/flywheel-energy-storage-calculator/implementation/

instrument implementation / implementation-contract

# Flywheel Energy Storage Calculator implementation

A source-bound implementation contract for Flywheel Energy Storage Calculator; deployment and executable qualification remain separate.

Status: **VERIFIED_WITH_ERRATA**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-with-binding-errata

**Evidence ID**: t4-249

**Effect**: Computation or source lookup only

## Input and validation requirements

The zero-average-speed input makes Cs and required inertia undefined because the denominator vanishes; the calculator should reject it. The unit probe also exposes a large numerical error if rpm is interpreted as rad/s without conversion.

## Required corrections

````
[
  {
    "vector": 2,
    "field": "required_I_kg_m2",
    "wrong": 0.5066059,
    "correct": 5.0660592,
    "cause": "reported target/ΔE (dimensionless scale factor) instead of I×that"
  },
  {
    "vector": 4,
    "field": "required_I_kg_m2",
    "wrong": 1.4248291,
    "correct": 1.1398633,
    "cause": "same scale-factor bug"
  }
]
````

## Inspectable interface fixture

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

````
{
  "inputs": {
    "I_kg_m2": 2.5,
    "omega_min_rad_s": 98,
    "omega_max_rad_s": 102,
    "omega_avg_rad_s": 100,
    "target_deltaE_J": 1000
  },
  "expected_outputs": {
    "KE_at_omega_avg_J": 12500,
    "Cs": 0.04,
    "deltaE_J": 1000,
    "required_I_kg_m2": 2.5
  },
  "working": "KE=0.5*2.5*100^2=1.25*10000=12500 J. Cs=(102-98)/100=4/100=0.04. deltaE=2.5*100^2*0.04=2.5*10000*0.04=1000 J. I_required=1000/(100^2*0.04)=1000/400=2.5 kg·m²."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/flywheel-energy-storage-calculator/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/flywheel-energy-storage-calculator/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/flywheel-energy-storage-calculator/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-tranche4/tranche4-results.json`

- `tranche errata record`