# 📐 L2 Spec — Compressible Navier-Stokes — viscous shock/boundary-layer Mismatch-Only Spec
**ID:** `L2-171-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-171`](/artifact/l1/L1-171)
> **🎯 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 – 8192 |
| W | px | 32 – 8192 |
| Z | — | 16 – 2048 |
| M mach | — | 0.01 – 30 |
| Snr db | dB | 0 – 40 |
| N times | — | 100 – 1000000 |
| K error | — | 0.0 – 0.2 |
| Bc error | — | 0.0 – 0.3 |
| Mu error | — | 0.0 – 0.2 |
| Eos error | — | 0.0 – 0.1 |
## 2. Tolerance (ε)
**Type:** `fn`
```
14.0 + 0.3*SNR_dB - 15.0*mu_error - 15.0*k_error - 30.0*eos_error - 8.0*bc_error
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.48 |
| Delta tier | 5 |
## 4. Fingerprint
`ac45dc31747cdb3e9a27eb75ecc6721880adc511cd3887e3f19fa0cc36a569e8`
## 5. On-chain Registration
- **Chain hash:** `0x98ebcf9e139a63dc05b43b65edcfbd2b1d1bf9dbfe7d37072c47da1dbea0140d`
- **Chain tx hash:** `0xe4b3f21bb583570cbb00cf637f83de19c970f0f39fe1e6f8e67166be26143943`
- **Chain block:** `41553968`
---
## File Mapping
This bundle consists of: `L2-171-001.md`, `L2-171-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-171-001.md` | Source of truth — edit this | Human or LLM |
| `L2-171-001.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 `L2-171-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._