IYAMAM / ENGINEERING TOOLS
A useful place
to work things out.
Conversions and preliminary sizing for the MEP design desk.
MECHANICAL / HVAC
Room cooling
estimate.
A quick early-stage capacity range for customers and concept discussions. Enter the room, occupancy and exposure.
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For concept discussion only.
Preliminary sizing aid only. Final cooling capacity shall be determined from a detailed heat-load calculation considering orientation, envelope U-values, glazing, occupancy, lighting, infiltration/fresh air, equipment gains and design conditions.
How this relates to your uploaded load sheet +
Your spreadsheet is a detailed component worksheet covering solar glass, walls, roof, infiltration, people, lighting, equipment, duct allowances and outdoor air. This public calculator deliberately uses fewer inputs and displays a ±15% range. IYAMAM should complete a project heat-load calculation before selecting equipment.
SI + IMPERIAL
The unit converter.
Cooling, airflow, pressure, dimensions, electrical quantities and more.
26 quantity groups. SI and explicitly labelled imperial units. Temperature and temperature difference are kept separate.
ELECTRICAL
Power, current
and energy.
Convert between kW, kVA and current with an entered power factor, or turn energy use into average demand.
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This is a balanced-load relationship, not cable, breaker, voltage-drop or fault-level selection.
ENERGY TO DEMAND
kWh ÷ operating hours = average kW
AIR DISTRIBUTION
Duct sizing, with the working shown.
Find a circular or rectangular size using equal friction or velocity criteria, with the calculation shown.
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Excludes fittings, transitions, terminals and equipment. This straight-run result is not the required fan static pressure.
| Internal size | Velocity | Friction | Criteria |
|---|
Calculation method, scope & original manufacturer tools +
The IYAMAM browser calculator uses continuity, Darcy–Weisbach and an iterative Colebrook equation. For rectangular ducts it uses the hydraulic-diameter approximation Dₕ = 2ab/(a+b), not the circular-equivalent method. Results can differ from other duct-sizing software. Candidate dimensions run from 100 to 2,000 mm in 25 mm increments; availability must be checked.
The Darcy friction factor is 64/Re in laminar circular flow. The larger of laminar and Colebrook estimates is reported in the transitional range (Re 2,300–4,000), where the result is uncertain. Hydraulic-diameter treatment of rectangular flow is approximate, particularly outside turbulent conditions. These calculations do not model fitting losses, system balancing, acoustics or leakage.
For the original manufacturer software, use Daikin Applied’s official Duct Sizer and Pipe Sizer resources ↗. The tool on this page is independently built for IYAMAM; it is not McQuay or Daikin software.
Reference: ASHRAE Fundamentals — Duct Design ↗CHILLED-WATER DISTRIBUTION
Start with flow.
Find the bore.
Compare carbon-steel Schedule 40 pipe sizes using internal diameter, velocity and straight-pipe friction.
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Excludes fittings, valves, coils and equipment. The displayed loss is not a complete pump-head selection.
| Nominal / internal bore | Velocity | Friction | Criteria |
|---|
Calculation method, assumptions & pipe dimensions +
Flow from load is Q = P/(ρcₚΔT). Velocity is flow divided by internal area. Straight-pipe friction is fρv²/(2D), using the Darcy factor from Colebrook for turbulent flow and 64/Re for laminar flow. A conservative estimate is used and flagged for the transitional range. Fluid head is Δp/(ρg), with g = 9.80665 m/s².
The candidates are DN 15–300 carbon-steel Schedule 40. Internal bore is nominal outside diameter minus twice nominal wall thickness; DN is not the internal bore. Published dimensional tolerances, the project’s material specification and actual product data still apply. User-entered velocity and friction limits are selection criteria, not a code-compliance check.
Pipe dimensions: Atlas Steels, 8 April 2021 ↗
For a complete circuit, calculate every segment and add the applicable fittings and equipment losses. In a closed hydronic loop, building height alone is not added to the circulating pump’s friction head.