THERMAL TYPE FLOWMETER

A thermal, flow measuring device for determining and/or monitoring a mass flow of a measured medium, comprising a sensor element (1, 11, 21) having a measuring tube (2, 12, 22) with a tube wall (7, 17, 27) and with at least a first and a second temperature sensor element, which are especially embodied as resistance thermometers (3, 13, 23, 33), wherein at least one of the temperature sensor elements is heatable, wherein the measuring tube (2, 12, 22) has a longitudinal axis (A) and a tube contour (8, 18, 28) with a first tube cross section in the end regions of the measuring tube (2, 12, 22), wherein the measuring tube (2, 12, 22) includes a narrowing having a second tube cross section, which differs in form and/or area from the first tube cross section, wherein the narrowing is divided into at least two segments (6, 16, 26), wherein at least one of the segments (6, 16, 26) is angled relative to the longitudinal axis (A) of the measuring tube (2, 12, 22) by an angle (α) of at least 5° and wherein, in each case, one of the temperature sensor elements is arranged in a respective one of the two segments (6, 16, 26) externally on the tube wall (7, 17, 27) of the measuring tube (2, 12, 22) and is located in thermal contact with the measured medium.