# 📐 L2 Spec — Incompressible Navier-Stokes — low-Mach viscous flow Mismatch-Only Spec
**ID:** `L2-170-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-170`](/artifact/l1/L1-170)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.48 · **Delta tier:** 5
> **⛓ On-chain block:** 41553968
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| H | px | 32 – 4096 |
| W | px | 32 – 4096 |
| Z | — | 16 – 1024 |
| Re | — | 1 – 100000000.0 |
| Snr db | dB | 0 – 40 |
| N times | — | 50 – 100000 |
| Bc error | — | 0.0 – 0.2 |
| Nu error | — | 0.0 – 0.1 |
| Initial condition error | — | 0.0 – 0.3 |
## 2. Tolerance (ε)
**Type:** `fn`
```
15.0 + 0.3*SNR_dB - 30.0*nu_error - 10.0*bc_error - 10.0*initial_condition_error
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.48 |
| Delta tier | 5 |
## 4. Fingerprint
`e588b39f4364d0413121c00f1176362cdf3aa2e1fadf5e5e6b3de9f891ef40cc`
## 5. On-chain Registration
- **Chain hash:** `0x2e2eba2cce4d51e026d7a19e403a84bf6b86aa28e724b83860e313baf46c0771`
- **Chain tx hash:** `0x06c22ca96a1bd1205a3fb8712dcf910a84277f93cd2612bd24eb3d7f681634e4`
- **Chain block:** `41553968`
---
## File Mapping
This bundle consists of: `L2-170-001.md`, `L2-170-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-170-001.md` | Source of truth — edit this | Human or LLM |
| `L2-170-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |
**Prompt for your LLM after editing this Markdown:**
> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.
_This Markdown was auto-synthesized from the catalog row for `L2-170-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._