# Trapezoidal Channel Manning Normal & Critical Depth Energy Calculator

> Trapezoidal Channel Manning Normal & Critical Depth Energy Calculator is a paid API for AI agents from detect.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-11-04).

Computes normal depth, critical depth, flow states, and energy for a trapezoidal open channel using Manning's equation.

## Facts

- Endpoint: POST https://detect.halowerk.com/v1/F-TD2000-GEO-INDUSTRY-B007/trapezoidal-channel-manning-normal-critical-depth-energy?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-04
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/trapezoidal-channel-manning-normal-critical-depth-energy-calculator-6a2a8546
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_GnLlpws8pp2_V8HGsrOm8

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability trapezoidal-channel-manning-normal-critical-depth-energy-calculator-6a2a8546 -d '<json body>'
```

Example prompt: Calculate the normal and critical depth for a trapezoidal channel with a bottom width of 3 meters, side slopes of 2 (H:V), Manning's n of 0.013, bed slope of 0.001, discharge of 10 cubic meters per second, and gravity of 9.81 m/s².

## When to prefer this

Use this endpoint when you need precise hydraulic computations for a trapezoidal open channel cross-section, specifically when both normal depth and critical depth are needed simultaneously along with energy and flow regime classification. Prefer this over generic fluid dynamics tools when the channel geometry is explicitly trapezoidal and Manning's equation is the governing flow model.

## Known failure modes

- Discharge too low or too high (outside 0.000001–1,000,000 range) returns validation error
- Bottom width outside 0.01–10,000 m range returns schema error
- Manning's n outside 0.001–1 range returns invalid input error
- Bed slope at or below 1e-8 or above 0.5 triggers range validation failure
- Side slope above 10 or below 0 returns invalid parameter error
- Gravity outside 0.1–100 range returns validation error
- Non-convergence of iterative normal depth solver may return computation error

## How this service works

Compute normal and critical flow states for an explicit trapezoidal channel model.

## Output

Returns computed hydraulic properties including normal depth, critical depth, flow velocity, hydraulic radius, cross-sectional area, wetted perimeter, specific energy, and Froude number for the specified trapezoidal channel, along with classification of flow regime (subcritical, critical, or supercritical).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "artifact": {
   "type": "object",
   "required": [
    "openChannel"
   ],
   "properties": {
    "openChannel": {
     "type": "object",
     "required": [
      "data",
      "claim"
     ],
     "properties": {
      "data": {
       "type": "object",
       "required": [
        "bottom_width",
        "side_slope",
        "manning_n",
        "bed_slope",
        "discharge",
        "gravity"
       ],
       "properties": {
        "gravity": {
         "type": "number",
         "maximum": 100,
         "minimum": 0.1
        },
        "bed_slope": {
         "type": "number",
         "maximum": 0.5,
         "minimum": 1e-8
        },
        "discharge": {
         "type": "number",
         "maximum": 1000000,
         "minimum": 0.000001
        },
        "manning_n": {
         "type": "number",
         "maximum": 1,
         "minimum": 0.001
        },
        "side_slope": {
         "type": "number",
         "maximum": 10,
         "minimum": 0
        },
        "bottom_width": {
         "type": "number",
         "maximum": 10000,
         "minimum": 0.01
        }
       },
       "additionalProperties": false
      },
      "claim": {}
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/trapezoidal-channel-manning-normal-critical-depth-energy-calculator-6a2a8546/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from detect.halowerk.com](https://www.zero.xyz/host/detect.halowerk.com/llms.txt)