Abstract: A device for measuring a volume flow in a ventilation pipe (1) comprises a sensor element (13) disposed on the mounting (8) and configured as a thermal anemometer. Upstream of the sensor element is a turbulence-generating element, which is configured and disposed at a distance from the sensor surface (18.1) such that highly turbulent flow is generated in the region of the sensor surface in a targeted manner. Downstream of the sensor surface is a flow element (20), which widens in the cross-section thereof in the flow direction (L), wherein starting from a height level of the sensor surface a height is reached that is greater than the height of the break-away edge (17.1) opposite the sensor surface.

Abstract: A device for measuring a volume flow in a ventilation pipe (1) comprises a mounting (8) that can be fixed in the ventilation pipe (1) and a sensor element (13) having a sensor surface (18.1), said element being disposed on the mounting (8) and configured as a thermal anemometer. Upstream of the sensor element (13) is a turbulence-generating element, for example in the form of a break-away edge (17.1), which is configured and disposed at a distance from the sensor surface (18.1) such that highly turbulent flow is generated in the region of the sensor surface (18.1) in a targeted manner. Downstream of the sensor surface (18.1) is a flow element (20), which widens in the cross-section thereof in the flow direction (L), wherein starting from a height level of the sensor surface (18.1) a height is reached that is greater than the height of the break-away edge (17.1) opposite the sensor surface (18.1).