HomeEnergy & ThermodynamicsThermal Mass & Night-Flush Cooling

Thermal Mass & Night-Flush Cooling

Interactive 3D building thermal-mass simulator: watch a lumped RC thermal model track indoor temperature against a day/night outdoor swing, toggle night-flush ventilation, and see how much peak cooling load a heavy building shell avoids versus a lightweight one.

Energy & Thermodynamics3DModerate60 FPS📱 Mobile-adapted⇄ 2D version
energy-topic-78 ↗ Open standalone

Buildings with heavy thermal mass — exposed concrete, masonry, thick rammed earth — absorb the day's heat slowly and release it hours later, flattening the indoor temperature swing that a lightweight structure would otherwise transmit almost instantly. This simulator runs a simplified RC (resistance-capacitance) thermal model of a single building zone against a sinusoidal outdoor day/night cycle, lets you switch the shell's thermal mass and toggle night-flush ventilation (pulling in cool night air to purge stored heat before the next day), and tracks how many degrees of peak indoor temperature — and therefore cooling load — that combination avoids compared to a lightweight, unflushed reference building.

⚙ Under the hood

Interactive 3D building thermal-mass simulator: a lumped RC thermal model tracks indoor temperature against a day/night outdoor swing, with toggleable night-flush ventilation that purges stored heat before the next day.

thermal massbuilding physicsnight flushpassive coolingRC thermal modelenergy balance

3D · Three.js / WebGL renderer · 60 FPS target · runs fully client-side, no install

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