LIVEdataset aec-bench@releasetasks 552models 18last submission … · built …
civilwith-tool

Orifice Outlet Design

Sizes a circular orifice outlet for a stormwater detention basin by rearranging the orifice equation Q = Cd*A*sqrt(2gH) to solve for the required orifice area and diameter given a target discharge flow rate and available head. Commonly applied in urban stormwater management to control post-development peak flows.

with-tool: The model is given an executable Python calculator script.

Standards

Hydraulics textbooks

Tags

civildetentionhydraulicsorificestormwater

How this task is generated

One template produces many comparable benchmark tasks while keeping the scoring contract fixed.

  1. 01

    Template

    The reusable contract shown on this page.

  2. 02

    Scenario

    An archetype and site context are sampled.

  3. 03

    Difficulty tier

    Inputs may be hidden at harder tiers.

  4. 04

    Task prompt

    The model responds with the declared outputs.

Parameters

Inputs the model receives, and the outputs it is scored on.

Inputs

3 inputs

Always given

Included directly in every task prompt.

1

  • Design flow

    design_flow_m3_s

    Target discharge flow rate Q

    0.005 – 2 m³/s

Derived from scenario

Sampled from the scenario and inferable from its description.

1

  • Head above centreline

    head_above_centreline_m

    Head of water above orifice centreline H

    Derived from the archetype scenario. Hidden at hard difficulty.

    0.1 – 5 m

Optional

Used only when the sampled task needs this part of the contract.

1

  • Discharge coefficient

    discharge_coefficient

    Orifice discharge coefficient Cd

    Derived from the archetype scenario. Optional input. Hidden at hard difficulty.

    0.4 – 0.8

Scored outputs

3 outputs

Required orifice area m2

required_orifice_area_m2

Required orifice area A (m²)

Scores if within ±3% of the reference value.

Orifice diameter

orifice_diameter_mm

Orifice diameter D (mm)

Scores if within ±3% of the reference value.

Discharge velocity m s

discharge_velocity_m_s

Discharge velocity through orifice v (m/s)

Scores if within ±3% of the reference value.

Difficulty

Each template is sampled at three tiers. Harder tiers may hide inputs, forcing the model to infer them from the scenario description.

easy

All inputs given

All parameters given, standard discharge coefficient

Discharge coefficient restricted to: 0.61

medium

All inputs given

All parameters given, variable discharge coefficient

hard

Some inputs hidden

Discharge coefficient and head hidden, agent must infer from site context

Hidden inputs

  • Discharge coefficientdischarge_coefficient
  • Head above centrelinehead_above_centreline_m

Prompt replacement text

The detention basin is a {{ archetype.description }} ({{ archetype.site_context }})

Task bundle

The exact instruction and parameter contract used to generate this task, pinned to the published library source.

/workspace

  • instruction.md
  • orifice-outlet-design_calc.py

Teal lines show Jinja input conditions, not task visibility policy. A line renders only when that input or tool is visible.

1You are a senior civil engineer specializing in stormwater management and detention basin design.2 3## Problem4 5Size an orifice outlet to achieve a target release rate from a detention basin using the orifice flow equation.6 7## Given8 9| Parameter | Value | Unit |10|-----------|-------|------|11| Design discharge (Q) | {{ design_flow_m3_s }} | m³/s |12{% if head_above_centreline_m is defined %}13| Head above orifice centreline (H) | {{ head_above_centreline_m }} | m |14{% endif %}15{% if discharge_coefficient is defined %}16| Discharge coefficient (Cd) | {{ discharge_coefficient }} | - |17{% endif %}18{% if archetype_description is defined %}19 20### Site Conditions21 22{{ archetype_description }}23{% endif %}24 25{% if tool_available %}26## Available Tool27 28An orifice sizing calculation tool is available at `/workspace/orifice-outlet-design_calc.py`. Run it with:29 30```bash31python3 /workspace/orifice-outlet-design_calc.py --help32```33 34You may use this tool to verify your calculations or compute values directly.35{% endif %}36 37## Required38 39Calculate the following:40 411. Required orifice area A (m²)422. Orifice diameter D (mm)433. Discharge velocity through the orifice v (m/s)44 45## Applicable Standards46 47- Standard hydraulics textbook orifice flow equations48 49## Constraints50 51- No internet access is available. Work from engineering knowledge and the provided tool.52- Use the orifice flow equation:53 - **Q = Cd × A × √(2gH)**54 - Rearranged for area: **A = Q / (Cd × √(2gH))**55 - Diameter from area: **D = √(4A / π)**56 - Discharge velocity: **v = √(2gH)**57- Use g = 9.81 m/s²58- If no discharge coefficient is given, use Cd = 0.61 (sharp-edged circular orifice)59- The orifice is assumed to be circular and fully submerged60 61## Output Format62 63Show your step-by-step working in Markdown, including formulas and intermediate calculations. At the end of your solution, include a JSON block with your final answers in exactly this format:64 65```json66{67 "required_orifice_area_m2": <numeric_value>,68 "orifice_diameter_mm": <numeric_value>,69 "discharge_velocity_m_s": <numeric_value>70}71```72 73Write your complete solution to `/workspace/output.md`.74

Scenario archetypes

Each generated task is drawn from one of these realistic scenario bands.

Site contexts ground each scenario in a real locale the model can use to infer hidden values.

Small urban basin

small_urban_basin

Small urban detention basin with low head

sydney-infill-residentialmelbourne-suburban-subdivision
Parameter ranges
head_above_centreline_m
0.3 – 1
discharge_coefficient
0.59 – 0.63

Medium commercial basin

medium_commercial_basin

Medium commercial development detention basin

brisbane-commercial-parkadelaide-retail-precinct
Parameter ranges
head_above_centreline_m
0.8 – 2
discharge_coefficient
0.58 – 0.62

Large regional basin

large_regional_basin

Large regional stormwater detention facility

perth-regional-wetlandgold-coast-flood-control
Parameter ranges
head_above_centreline_m
1.5 – 4
discharge_coefficient
0.6 – 0.65

Shallow linear basin

shallow_linear_basin

Shallow linear detention basin along road corridor

canberra-road-corridortownsville-drainage-channel
Parameter ranges
head_above_centreline_m
0.1 – 0.5
discharge_coefficient
0.55 – 0.6

Example task

sydney-infill-residential-small-urban-basin-preview — hard difficulty, some inputs hidden.

Small urban detention basin with low head. sydney-infill-residential. Required outputs: required_orifice_area_m2, orifice_diameter_mm, discharge_velocity_m_s

The model sees

Scenario context and visible inputs.

design_flow_m3_s
0.005 to 2 m³/s

Executable tool: orifice-outlet-design_calc.py

The model must infer

Inputs withheld at this difficulty.

  • Head above centreline

    head_above_centreline_m

  • Discharge coefficient

    discharge_coefficient

Stand-in text in the prompt

The detention basin is a {{ archetype.description }} ({{ archetype.site_context }})

The model must produce

The scored JSON answer schema.

{
  "required_orifice_area_m2": <number>,
  "orifice_diameter_mm": <number>,
  "discharge_velocity_m_s": <number>
}
  • required_orifice_area_m2 · scored within ±3%
  • orifice_diameter_mm · scored within ±3%
  • discharge_velocity_m_s · scored within ±3%