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

Npsh Available

Calculates NPSH available from suction vessel absolute pressure, liquid level relative to the pump, suction pipe losses, fluid vapor pressure, and density. The template converts pressure terms to metres of fluid head and compares NPSHa with explicit NPSH required to report cavitation margin.

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

Standards

Hydraulic Institute Standards

Tags

cavitationdeterministicmechanicalnpshpump-hydraulics

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

6 inputs

Always given

Included directly in every task prompt.

6

  • Suction vessel pressure

    suction_vessel_pressure_kpa_abs

    Absolute pressure at the suction vessel free surface

    30 – 800 kPa abs

  • Liquid level above pump

    liquid_level_above_pump_m

    Static liquid level above the pump centreline

    -6 – 20 m

  • Suction pipe losses

    suction_pipe_losses_kpa

    Suction-side friction and minor losses

    0 – 150 kPa

  • Vapor pressure

    vapor_pressure_kpa_abs

    Fluid vapor pressure at operating temperature

    0.5 – 100 kPa abs

  • Fluid density

    fluid_density_kg_m3

    Fluid density

    600 – 1300 kg/m3

  • Npsh required

    npsh_required_m

    Pump manufacturer's NPSH required

    0.5 – 20 m

Scored outputs

6 outputs

Pressure head

pressure_head_m

Suction pressure head

Scores if within ±3% of the reference value.

Vapor pressure head

vapor_pressure_head_m

Vapor pressure head

Scores if within ±3% of the reference value.

Loss head

loss_head_m

Suction loss head

Scores if within ±3% of the reference value.

Npsh available

npsh_available_m

Net Positive Suction Head Available

Scores if within ±3% of the reference value.

Cavitation margin

cavitation_margin_m

NPSHa minus NPSH required

Scores if within ±3% of the reference value.

Margin ratio

margin_ratio

NPSHa divided by NPSH required

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.

All inputs remain visible at every tier

For this template, difficulty scales through parameter and scenario ranges rather than hidden information.

easy:
All parameters given for flooded water suction
medium:
All parameters given across water and process suction cases
hard:
All parameters given for hot liquid or pressurised suction cases

Task bundle

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

/workspace

  • instruction.md
  • npsh-available_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 mechanical engineer specializing in pump hydraulics.2 3## Problem4 5Calculate Net Positive Suction Head Available at a pump inlet and compare it with the pump NPSH required.6 7## Given8 9| Parameter | Value | Unit |10|-----------|-------|------|11| Suction vessel pressure | {{ suction_vessel_pressure_kpa_abs }} | kPa abs |12| Liquid level above pump centreline | {{ liquid_level_above_pump_m }} | m |13| Suction pipe losses | {{ suction_pipe_losses_kpa }} | kPa |14| Fluid vapor pressure | {{ vapor_pressure_kpa_abs }} | kPa abs |15| Fluid density | {{ fluid_density_kg_m3 }} | kg/m3 |16| NPSH required | {{ npsh_required_m }} | m |17 18{% if archetype_description is defined %}19### Pump Suction Context20 21{{ archetype_description }}22{% endif %}23 24{% if tool_available %}25## Available Tool26 27An NPSH calculation tool is available at `/workspace/{{ meta.name }}_calc.py`. Run it with:28 29```bash30python3 /workspace/{{ meta.name }}_calc.py --help31```32 33You may use this tool to verify your calculations or compute values directly.34{% endif %}35 36## Required37 38Calculate the following:39 401. Suction pressure head (m)412. Vapor pressure head (m)423. Suction loss head (m)434. NPSH available (m)445. Cavitation margin (m)456. Margin ratio NPSHa/NPSHr46 47## Constraints48 49- No internet access is available. Work from engineering knowledge and the provided tool.50- Use g = 9.81 m/s2.51- Convert pressure in kPa to head in metres of fluid using head = pressure x 1000 / (density x g).52- Use NPSHa = pressure head + static level - vapor pressure head - loss head.53- Use cavitation margin = NPSHa - NPSH required.54- Use margin ratio = NPSHa / NPSH required.55 56## Output Format57 58Show your step-by-step working in Markdown. At the end of your solution, include a JSON block with your final answers in exactly this format:59 60```json61{62 "pressure_head_m": <numeric_value>,63 "vapor_pressure_head_m": <numeric_value>,64 "loss_head_m": <numeric_value>,65 "npsh_available_m": <numeric_value>,66 "cavitation_margin_m": <numeric_value>,67 "margin_ratio": <numeric_value>68}69```70 71Write your complete solution to `/workspace/output.md`.72

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.

Flooded water suction

flooded_water_suction

Flooded suction water pump with atmospheric vented tank

water-treatment-transferbuilding-services-break-tank
Parameter ranges
suction_vessel_pressure_kpa_abs
98 – 103
liquid_level_above_pump_m
1 – 8
suction_pipe_losses_kpa
2 – 20
vapor_pressure_kpa_abs
2 – 8
fluid_density_kg_m3
990 – 1000
npsh_required_m
1 – 5

Hot process liquid

hot_process_liquid

Hot process liquid suction with elevated vapor pressure

industrial-process-skidthermal-utility-loop
Parameter ranges
suction_vessel_pressure_kpa_abs
100 – 250
liquid_level_above_pump_m
-2 – 6
suction_pipe_losses_kpa
10 – 60
vapor_pressure_kpa_abs
25 – 90
fluid_density_kg_m3
850 – 1000
npsh_required_m
3 – 12

Pressurised suction vessel

pressurised_suction_vessel

Pump drawing from a pressurised suction vessel

chemical-transfer-vesselpressure-booster-skid
Parameter ranges
suction_vessel_pressure_kpa_abs
200 – 700
liquid_level_above_pump_m
-4 – 10
suction_pipe_losses_kpa
15 – 120
vapor_pressure_kpa_abs
2 – 60
fluid_density_kg_m3
700 – 1100
npsh_required_m
4 – 18

Example task

industrial-process-skid-hot-process-liquid-preview — hard difficulty, all inputs given.

Hot process liquid suction with elevated vapor pressure. industrial-process-skid. Required outputs: pressure_head_m, vapor_pressure_head_m, loss_head_m, npsh_available_m, cavitation_margin_m, margin_ratio

The model sees

Scenario context and visible inputs.

suction_vessel_pressure_kpa_abs
100 to 250 kPa abs
liquid_level_above_pump_m
-2 to 6 m
suction_pipe_losses_kpa
10 to 60 kPa
vapor_pressure_kpa_abs
25 to 90 kPa abs
fluid_density_kg_m3
850 to 1000 kg/m3
npsh_required_m
3 to 12 m

Executable tool: npsh-available_calc.py

The model must infer

Inputs withheld at this difficulty.

Nothing. All inputs are supplied.

The model must produce

The scored JSON answer schema.

{
  "pressure_head_m": <number>,
  "vapor_pressure_head_m": <number>,
  "loss_head_m": <number>,
  "npsh_available_m": <number>,
  "cavitation_margin_m": <number>,
  "margin_ratio": <number>
}
  • pressure_head_m · scored within ±3%
  • vapor_pressure_head_m · scored within ±3%
  • loss_head_m · scored within ±3%
  • npsh_available_m · scored within ±3%
  • cavitation_margin_m · scored within ±3%
  • margin_ratio · scored within ±3%