läpivirtaama
Läpivirtaama is a Finnish term that refers to a specific type of forward‑flow pump used primarily in water supply and irrigation systems. The name is a compound of the Finnish words “läpivirtat”, meaning unidirectional flow, and the suffix “‑ama”, which denotes a device or apparatus. Unlike impulse pumps that use rotating impellers, a läpivirtaama relies on a simple screw or butterfly acting as an obstructions to create pressure differences even with minimal energy input.
The first recorded designs of the läpivirtaama appeared in the 1950s within the Finnish Water Research Institute,
Modern iterations of the läpivirtaama incorporate molded plastic housings to reduce corrosion and a seal system
In environmental engineering, läpivirtaama pumps are valued for their simplicity and resilience to sediment build‑up, as