History of Heat Pipes and NASA’s Contribution

The concept of the heat pipe was first introduced by U.S. engineer Richard S. Gaugler in 1942, but its development into a mature technology was largely driven by NASA in the 1960s.
In 1963, George M. Grover at Los Alamos National Laboratory conducted systematic research and experiments on modern heat pipes, coining the term “heat pipe.” NASA quickly recognized the value of this device for spacecraft thermal control: it could transfer heat efficiently in zero gravity, with no moving parts, minimal weight, and outstanding reliability.
NASA subsequently applied heat pipes extensively in satellites and spacecraft to dissipate heat from electronics, regulate cabin temperatures, and cool propulsion components—laying a solid foundation for today’s energy-saving applications in cleanroom HVAC and building air-handling systems.

How Heat-Pipe Dehumidification Works

– Temperature-Driven Operation – The pre-cool and reheat sections of a U-type heat pipe use the temperature difference across a cooling coil to drive phase-change heat transfer. No external energy is required; only the cooling section consumes a small amount of chilled water or DX capacity.
– Pre-Cool + Reheat – Incoming air passes through the pre-cool section, lowering enthalpy and enhancing moisture removal. The reheat section then raises the supply air temperature, avoiding overcooling and reducing terminal reheat demand.
– Calculation Formula – Heat transfer can be estimated using Q = V × ρ × Cₚ × ΔT / 3600 (V: airflow, ρ: air density, Cₚ: specific heat, ΔT: temperature difference).

Key Benefits

– Significant Energy Savings – The pre-cool section reduces sensible load on the coil, while the reheat section recovers energy from the leaving air stream. This combination reduces mechanical reheat. Typical projects report 20–30% energy savings, with sample data showing annual savings of 66,528 kWh and 115 t of steam.
– Low Maintenance & Reliability – With no moving parts and low airside resistance, heat pipes offer stable performance and minimal upkeep.
– Stable Supply Air – The reheat section controls supply air temperature, avoiding overcooling and excessive terminal reheat.
– GMP Compliance – Adding heat pipes does not alter AHU structure or airflow parameters, so GMP and ISO validations remain unaffected.

Design and Installation Notes

– Space Requirements – Allow at least 300 mm of unit length for both pre-cool and reheat sections. The U-bend (insulated end) requires ~150 mm of space.
– Filtration & Drainage – Install at least a pre-filter upstream of the pre-cool section. Place the section over a drain pan and include baffles to prevent bypass air.
– Unit Size & Fan Power – Adding a heat pipe increases coil section length by 400–600 mm and width by ~150 mm. Airside pressure drop rises by 100–120 Pa, adding only about 2–3% fan power.
– Installation Options – Heat pipes can be factory-mounted inside AHU cooling sections or installed in two parts upstream and downstream of the coil, connected at the rear of the unit. Left- and right-hand configurations are available.

Sizing Example: At 10,000 m³/h, a standard heat-pipe module provides approximately 21.7 kW of capacity with an airside resistance of 147 Pa. Non-standard configurations and energy-monitoring panels are available.

Typical Applications

– Semiconductor wafer fabs and electronics clean zones
– Biopharmaceutical research and aseptic production rooms
– Optical, LED, and display manufacturing lines
– Food and packaging clean areas
– Hospital operating rooms and advanced laboratories

These environments often require enhanced dehumidification and reduced reheat energy while maintaining ISO or GMP supply air conditions.

CLEEMS Implementation Strategy

– Integrated Solutions – Combine heat-pipe dehumidification with FFU + LED lighting + airflow control systems for a triple optimization of cleanliness, humidity, and energy consumption.
– Turnkey Delivery – CLEEMS provides self-supporting, column-free enclosures, modular ceilings, and flexible return air layouts that meet ISO 6–8 and GMP requirements.
– Energy Audits & ROI – We evaluate local climate and process conditions, validate savings (kWh, steam, cost), and provide a clear return-on-investment plan.

Contact Us

Interested in integrating NASA-grade heat-pipe dehumidification into your cleanroom or AHU/MAU system? Contact CLEEMS Cleanroom System Engineering & Material  Ltd. for a tailored energy analysis and turnkey implementation plan.