Cooling calculations & sources
Mechanical cooling · setpoint met
- Liquid duty
- 2,070 / 2,070 kW · delivered / requested
- Facility water
- 73°F → 92°F
- Primary flow
- 2880 L/min
- Secondary flow
- 2150 L/min
- External Δp
- 161 kPa · assumed system curve
- Compressor
- 207 kW · estimated COP 10.0
- Pumps + fans
- 37 kW · estimate; heat excluded
- Residual air load
- 306 kW · separate air system
- Liquid heat rejection
- 2,277 kW
- Tower water
- 85°F → 93°F
- Evaporation
- 11.9 GPM · 80% latent assumption
- Blowdown
- 3.9 GPM · 4 cycles
- Total makeup
- 15.8 GPM · includes drift
GB200 NVL72
Blackwell · 2025
18 compute + 9 NVLink trays; 72 GPUs, 36 CPUs. Design assumptions: 82°F supply, 132 kW rack, 115 kW liquid.
- Supply water
- 82°F
- Return water
- 107°F · ΔT 25°F
- Loop flow
- 568 GPM · 119 L/min per rack
- Per GPU
- 1,200 W · 4,095 BTU/h
- Per rack
- 132 kW · 115 to water · 17 air
- 18 racks
- 2.4 MW · 8.1 MBTU/h · 676 tons
- Junction estimate
- 127°F · uncalibrated
Die basis: assumed junction-to-mean-water resistance 0.027 °F/W; no verified throttle limit.
Model basis & sources
Design-point explainer, not an OEM equipment selection. Treated water: 995 kg/m³, 4.18 kJ/kg·K. No glycol/freeze model. Sea level, 5–46°C outdoor range. Wet bulb uses an approximate ventilated-psychrometer relation.
Rack powers, GPU TDP, thermal resistance, pipe sizes, pump system curve, 3 MW plant rating and COP are assumptions. Temperatures at a capacity limit describe the deliverable load only. Auxiliaries are reported separately; their heat is outside the liquid balance. Residual rack air cooling is outside this plant.
Trane centrifugal chiller / water-box arrangement
Water-box isolation and service principles. Internal geometry here is representative.
Baltimore Aircoil / counterflow towers
Opposed air/water flow, fill, and overhead spray distribution.
NVIDIA Blackwell / two-die GPU
Two linked dies per Blackwell GPU package. Floorplan and package scale are illustrative.
NVIDIA GB200 hardware / tray inventory
Published inventory; cabinet dimensions are representative.
NVIDIA Vera Rubin / 45°C inlet
Published inlet and dry-cooling capability; remaining Rubin values are assumptions.
Vertiv XDU1350 planning guide
Cabinet dimensions and 20 L/s dual-pump reference. 1,350 kW at 5 K is a conservative scenario, not an OEM rating.
DOE cooling tower water balance
Makeup = evaporation + blowdown + drift.