A method for determining a thermal transport size and / or to a flow velocity in a flowing medium which is proportional to the size and flow - measuring arrangement

摘要

The invention relates to a method for determining a thermal transport size and / or to a flow velocity in a flowing medium (36) variable proportional to (v, d, m), comprising the steps of: (i) pulsed heating of the medium to be measured (36) by means of a heat source (12), (ii) measuring a first temperature (t₁), the a first distance (x₁) from the heat source (12) can be assigned, by means of a first temperature measuring means (14) as a function of time (t), (iii) measuring at least a second temperature (t₂) by means of a second temperature measuring means (16) in a second distance (x₂) from the heat source into a function of time (t), (iv) determining the thermal transport size (a) from – a only temperature - maximum value (t_{max (1)}), the maximum achieved first temperature and – a second temperature - maximum value (t_{max (2)}), the maximum achieved second temperature and / or (v) determining the flow velocity (v) with reference to – a first maximum temperature - point in time (t_{max (1)}), to which the first temperature (t₁) the only temperature - maximum value (t_{max (1)}) passes through, and – of a second maximum temperature - point in time (t_{max (2)}), to said second temperature (t₂) the second temperature - maximum value (t_{max (2)}) passes through. According to the invention, it is provided that the determination of the quantity that is proportional to the flow velocity (v) and / or of the thermal transport size (a) with the use of at least of a shape factor (f), which for at least one temperature measuring means (14), a deviation of the heat source (12) from an ideal point - or lines heat source describes.