tyhjiöeristystä

Tyhjiöeristystä, known in English as vacuum insulation, is a method of thermal insulation that utilizes a vacuum to minimize heat transfer. It achieves this by creating a space between two or more surfaces from which most of the air has been removed. Since heat transfer through conduction and convection relies on the presence of a medium, eliminating air significantly reduces these modes of heat loss or gain.

The effectiveness of vacuum insulation stems from the near-complete absence of molecules that can carry heat. While some heat transfer still occurs through radiation and conduction across any remaining supports or seals, it is substantially lower than in traditional insulation materials like fiberglass or foam. This makes vacuum insulated panels (VIPs) highly efficient for their thickness.

Vacuum insulation is commonly employed in applications where space is limited and high thermal performance is required. Examples include high-performance refrigerators and freezers, building insulation for specialized projects, and in thermal containers for transporting temperature-sensitive goods. The construction typically involves an absorbent core material, often a silica aerogel or fiberglass, placed within an airtight envelope. The air is then evacuated from the space around the core, creating the vacuum. The integrity of the seal is crucial for maintaining the insulation's performance over time.