Apparatus and method for measuring the quality of steam
AssigneeTexaco Inc.
InventorSze-Foo Chien
Life of this patent
Estimating the term…
Abstract
Steam quality measuring and monitoring apparatus and methods which measures the quality of steam flowing in a steam pipe includes a test cell connected in line with the steam pipe so that the steam flows through the test cell. The capacitance, the dielectric constant, the temperature and the density of the steam flowing through the test cell are measured and monitored and the quality of the steam is derived in accordance with the steam density and temperature.
Claims6
Steam quality apparatus which measures and monitors the quality of steam flowing in a steam pipe comprising:
- a test cell connected in line with the steam pipe in a manner so that the steam flows through the test cell,
- capacitance sensing means contained within the test cell for providing a capacitance output corresponding to the capacitance of the steam,
- temperature sensing means for sensing the temperature of the steam and providing a temperature signal representative thereof,
- density determining means connected to the capacitance sensing means and to the temperature sensing means for monitoring the density of the steam flowing through the test cell, and
- means connected to the density determining means and to the temperature sensing means for deriving the steam quality in accordance with the steam density and the temperature signal and providing a steam quality output related thereto;
- and
- in which the density determining means includes:
- dielectric constant determining means connected to capacitance sensing means for utilizing the capacitance output to determine the dielectric constant of the flowing steam and providing a signal E corresponding thereto, and
- computer means connected to the dielectric electric constant determining means and to the temperature sensing means for determining the steam density in accordance with the following equation:
- ##EQU2## where E is the dielectric constant, T is temperature in degree Kelvin, T* equals T/298.15 and P is density in Kg/m.sup.3 while P* equals P/1000, and a.sub.1 through a.sub.10 are constants.
A method of measuring and monitoring the quality of steam flowing in a steam pipe comprising the steps of:
- connecting a test cell in line with the steam pipe in a manner so that the steam flows through the test cell,
- sensing the capacitance of the steam in the test cell,
- providing a capacitance output corresponding to the sensed capacitance,
- sensing the temperature of the steam,
- providing a temperature signal representative of the sensed temperature,
- utilizing the capacitance output and the temperature signal to determine the density of the steam,
- providing a steam density signal related to the determined density, and
- deriving a quality of the steam in accordance with the steam density and the temperature signals;
- and
- in which the density determining step includes:
- utilizing the capacitance output to determine the dielectric constant in accordance with the following equation
- C=bE
- where E is the dielectric constant and b is a constant depending on the design of the cylindrical capacitor,
- providing a dielectric constant signal representative of the determined dielectric constant,
- determining the steam density with a computer and in accordance with the following equation:
- ##EQU3## where E is the dielectric constant, T is temperature in degree Kelvin, and T* equals T/298.15 and P is density in Kg/m.sup.3, while P* equals P/1000, and a.sub.1 through a.sub.10 are constants, and
- providing a density signal P corresponding to the determined density.
Dependencies are inferred from the claim text.