| 摘要 |
<p>The invention relates to a method of measuring the stream of a physical magnitude correlating with the mass stream of a medium flowing through a duct, for example, the mass stream itself or the heat stream given off by said medium to a consumer station or derived therefrom. The invention has for its object to provide a method and a device of the kind set forth operating with excellent accuracy and reproduceability for long and short periods within a very large range of values. The invention proposes to measure the mass stream of the medium by arranging in the medium a streamline element, by imparting to at least one predetermined, thermally active part of the wall of said streamline element a predetermined temperature, which may vary along said wall part, by measuring the temperature of the medium in the thermally undisturbed medium, for example, upstream with respect to the streamline element, by measuring the temperature of the medium affected by said wall part in thermal respect such as the heat conduction capacity, the density, the viscosity and the specific heat and by assessing the mass stream from said temperatures and the physical properties of the medium.</p> |
