STIRLING ENGINES
Our revolutionary S3 uses advanced technology from Stirling engines. These engines stand out for approaching the theoretical maximum performance, known as Carnot efficiency, making them the optimal choice in terms of efficiency for thermal engines.
A Stirling engine is a thermal device that operates based on the expansion and compression of a gas, typically helium, through cycles of heating and cooling. Its fundamental principle is the transfer of heat between the gas and the external environment, without any exchange of mass.
The Stirling cycle is divided into four phases:
- Phase 1 – Isochoric Heating: The gas heats up, causing it to expand and push the piston.
- Phase 2 – Isothermal Expansion: The piston moves outward due to the expansion of the gas, performing mechanical work.
- Phase 3 – Isochoric Cooling: The gas cools, causing the piston to move inward.
- Phase 4 – Isothermal Compression: The piston moves inward while the gas is compressed.
The reverse cycle of the Stirling engine is a concept that involves reversing the working flow of the engine to function as a refrigeration machine instead of an engine. In contrast to a conventional Stirling engine that converts thermal energy into mechanical work, the Stirling cooler uses mechanical work to transfer heat from one space to another.
Our design incorporates two reverse Stirling engines in an innovative way. One engine is dedicated to cooling the samples, providing a controlled environment for freezing, while the second engine cools the condenser, enabling efficient removal of moisture released by the samples during the freeze-drying process. The notable advantage of these engines lies in their lack of circulating fluids, which not only eliminates the need of a compressor, minimising the risk of failure, but also simplifies software control avoiding fluctuations and heat losses associated with conventional fluid systems.
The use of Stirling engines in our S3 reflects our commitment to technological excellence and the optimal preservation of biological samples.
