High precision turbine flow meter for low flow rates - has average density made equal to that of fluid using hollow particulate matter and synthetic resin

摘要

The device consists of a turbine (2) rotating in a fluid body and which has a cylindrical hub assembly (3) containing two openings (4) in which short shafts engage. These shafts are fixed to the body. The turbine has a series of helicoidal blades (8) fixed to the hub and inclined w.r.t. the axis. The external radial faces carry a tubular element (9) which in turn carries helicoidal blades (20) directed radially. To obtain the required density for a gas the turbine is moulded with hollow particles while for heavy fluids a metal is used. The particles are in the form of spheres, made of a metallic oxide, with dimensions of less 100 microns.