High temperature heat pipes (also known as alkali metal heat pipes) are typically defined as heat pipes that operate between 400 and 1100°C. They are often used to provide precise temperature uniformity or provide high-temperature heat transfer. In these temperature ranges, many traditional heat transport methods and materials are not suitable for practical operations; whereas alkali-metal heat pipes provide robust, high power transport.
Fluid Options for High Temperature Heat Pipes
- Cesium 300 to 600°C (572 to 1,112°F)
- Potassium 400 to 1000°C (752 to 1,832°F)
- NaK 500 to 800°C (932 to 1472°F)
- Sodium 500 to 1100°C (932 to 2,012°F)
Envelope Material Options for Alkali Heat Pipes
ACT has experience with a variety of traditional and superalloys to withstand the high internal pressure associated with multi-phase metals. Some common envelope materials include Stainless Steel, Inconel Alloy 600, and Haynes. ACT will select the appropriate envelope for the working fluid and operating conditions.
Alkali Metal Heat Pipes Examples
Applications for Alkali Metal Heat Pipes
- Temperature Calibration & Control; Isothermalizing furnace elements
- Nuclear power
- Solar Thermal
- Heat Engine Receivers (Steam, Stirling, Brayton, Rankine)
- Heat Exchangers
- Hypersonic wing leading edges
- Waste heat recovery
- Thermoelectric Generators
Why choose ACT for your high temperature heat pipes?
The alkali metals used in high-temperature heat pipes are extremely reactive to water or air, so achieving purity and containment is of the utmost importance. The ACT facility is one of the few commercial facilities set up to safely handle the construction of these types of heat pipes. We have the dedicated lab space, safety measures, and experienced personnel to make and deliver properly sealed vessels that will safely operate for a long lifetime.
ACT engineers and technicians are able to draw on the experience gained from the company’s work with NASA on the Kilopower project starting in 2015, to deliver both alkali metal and titanium-water heat pipes to support NASA’s investigation into using small fission reactors for future space transportation and surface power applications.
We look forward to learning about your high-temperature application, contact ACT today!