aneroidisolu

Aneroidisolu, meaning "aneroid cell" in Finnish, refers to the sealed, flexible diaphragm within an aneroid barometer. This diaphragm is typically made of a corrugated metal, often a brass or beryllium-copper alloy, designed to expand and contract in response to changes in atmospheric pressure.

The interior of the aneroid cell is either partially evacuated to a near vacuum or contains a low-pressure gas. As external atmospheric pressure fluctuates, the difference in pressure between the inside and outside of the cell causes the diaphragm to move. When atmospheric pressure increases, the diaphragm is pushed inward; when it decreases, the diaphragm expands outward.

These small movements are then mechanically amplified and transmitted to a needle that indicates the atmospheric pressure on a calibrated dial. Aneroid barometers, utilizing aneroid cells, are commonly used for weather forecasting and altimetry due to their portability and robustness compared to mercury barometers. The sensitivity and accuracy of an aneroid barometer depend on the quality of the aneroid cell and the precision of the amplification mechanism.