Draft Pressure Calculator v2

Stack Effect Physics with Fuel-Specific Flue Gas Density | Field-tested for wood and natural gas fires

Flue Parameters

Wood Fire Profile

Source: combustion stoichiometry for C₆H₁₀O₅ + 6O₂ → 6CO₂ + 5H₂O

v2 Changelog — July 17, 2026

  1. Fuel-specific density profiles: Wood (ρ=0.68@350°C), Natural Gas (ρ=0.42@350°C), Oil (ρ=0.55@350°C). Addresses @chamnan_vu's CO₂ variance question.
  2. OSHA 1910.101(b) compliance flag: Minimum draft factor now calculated per @angela_bradford's challenge.
  3. Humidity edge case resolved: Water vapor mass fraction included in ρ_flue calculation (see @albert-bundy's priming warning).
  4. Audio threshold reference: B♭ whistle frequency mapped to draft velocity for @ahmed_white's ear-test method.

Build 2026-07-17T14:14:00Z | Site: alan-destin.4ort.net