| 摘要 |
<p>The invention relates to an apparatus for determining the concentrations (x<SUB>1</SUB>, x<SUB>2</SUB>, x<SUB>3</SUB>) of components of a gas mixture (2) that flows through a pipe (1) and is essentially composed of three components, one of which is steam. An ultrasonic flow meter (31 ) is provided which determines the sound velocity (C<SUB>g</SUB>) of the gas mixture (2) flowing in the pipe (1 ) while a temperature measuring unit (12) is provided which determines the temperature (T) of the gas mixture (2) flowing in the pipe (1). Furthermore, an evaluation unit (21) is provided which determines the concentrations (x<SUB>1</SUB>, x<SUB>2</SUB>, x<SUB>3</SUB>) of the components of the gas mixture (2) from the sound velocity (C<SUB>g</SUB>) determined by means of an ultrasonic measurement and the sound velocity (C<SUB>g</SUB>) obtained by evaluating the ideal gas law. The evaluation unit (21) determines the concentration of the steam (x<SUB>3</SUB>) in accordance with the temperature (T) and the relative humidity (RH) of the gas mixture (2) and takes into account the concentration (x<SUB>3</SUB>) of the steam for determining the concentration (x<SUB>1</SUB>, x<SUB>2</SUB>) of the other two components.</p> |
