Method for thermally determining mass flow of a gaseous medium and thermal mass flow meter
US9671266B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 2013 |
| Grant date | Jun 6, 2017 |
| Priority date | — |
| Expiry date | Nov 13, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/6965
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for determining mass flow of a gas by means of a mass flow meter, which has a first and a second temperature sensor, which can be flowed around by the gas. The first temperature sensor is heated with a heating power Q, wherein the mass flow of the medium is determined by means of a power coefficient PC=Q/ΔT as a function of a heating power Q and a temperature difference ΔTm=T1−T2 between the measured values of the temperature sensor. A corrected power coefficient PCcorr is determined, wherein at least one correction occurs by means of at least one recovery correction term Ki, wherein the recovery correction term Ki has the form Ki=Δx·u2/(2·cp), wherein u is the flow velocity and cp the heat capacity of the medium, Δx is an element of the set {Δ1; Δ2; Δ12}, Δ1:=e1−cr, Δ2:=e2−cr and Δ12:=e1−e2=Δ1−Δ2, e1 and e2 are the recovery factors of the first, respectively second, temperature sensors, and wherein cr is a constant reference value, for which holds cr≦1, especially cr=1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.