Spacesuit Liquid Cooling Garment Simulator (2D)

Astronaut Workload

Cooling Garment Controls

Cooling water flow 2.0 L/min

Inlet water temperature 15.0 °C

⚠ Core temperature rising toward heat-stress limit — increase flow or lower inlet temperature.

Live Readouts

Core body temp

37.0 °C

Outlet water temp

15.0 °C

Metabolic heat

117 W

Cooling removed

0 W

How it works

A network of narrow tubing carries chilled water against the astronaut's skin. Blood-borne metabolic heat conducts into the tube wall and is carried away by the flowing water — real convective heat transfer, governed by the water's mass flow rate and the temperature rise it picks up along the tube.

Q_cooling = ṁ · cp · ΔT_water           [convective transfer, ΔT = T_out − T_in]
ε = 1 − e^(−UA / (ṁ·cp))                [heat-exchanger effectiveness, NTU method]
Q_cooling = ε · ṁ·cp · (T_core − T_in)  [heat actually picked up this pass]
T_out = T_in + Q_cooling / (ṁ·cp)

C_core · dT_core/dt = Q_metabolic − Q_cooling   [core temperature integration]

Workload — sets metabolic heat production, from ~117 W at rest to ~700 W during heavy EVA work.
Cooling water flow — raises both the water's heat-capacity rate (ṁ·cp) and the tube-to-skin conductance UA, up to a saturation limit — more flow, more heat carried away per second.
Inlet water temperature — the chiller/ice-water temperature entering the garment; lower inlet widens ΔT and increases cooling for the same flow.

If Q_metabolic exceeds Q_cooling for long enough, the body's thermal mass keeps absorbing the surplus and core temperature climbs toward the ~38 °C heat-stress threshold — genuinely integrated here, not scripted.

Cool water (inlet) Warm water (heat picked up)