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US 6,474,137 B1Granted
Measuring relative density of a gas
AssigneeLattice Intellectual Property Limited
InventorsPaul Stephen Hammond, Robert Richard Thurston
Life of this patent
Estimating the term…
Abstract
A method and apparatus for measuring the relative density of a gas, for example natural gas. The gas is supplied through an inlet to a chamber and is output through an outlet. Using a control and an ultra-sonic transducer emitter and an ultra-sonic transducer receiver, the speed of sound in the gas corrected to standard conditions is calculated. Then, the control operates to measure the relative density RD of the gas using the formula RD=a×SoSsc+b, where SoSsc is the speed of sound in the gas corrected to standard conditions, and a and b are constants.
Claims18
A method of determining a relative density of a gas comprising:
- precalculating a slope and an intercept of a linear relationship, between the relative density and a speed of sound, by taking a predetermined number of measurements of an initial relative density and a corresponding initial speed of sound in the gas;
- measuring the speed of sound in the gas;
- and
- calculating the relative density of the gas from the linear relationship using the slope, the intercept and the corresponding measured speed of sound.
1 more element
An engine comprising:
- means for receiving a supply of oxygen;
- means for receiving a supply of fuel gas;
- an oxygen/fuel gas ratio control system;
- control means for adjusting an oxygen/fuel gas ratio of a gas fired process, comprising,
- means for precalculating a slope and an intercept of a linear relationship between a relative density and a speed of sound,
- means for measuring the speed of sound in the oxygen/fuel gas, and
- means for using a measured speed of sound for determining the relative density of a fuel gas for the gas fired process;
- and
- means for adjusting an oxygen/fuel gas ratio control system for the gas fired process in accordance with the determined relative density,
- wherein said control means is programmed to precalculate the slope and the intercept of the linear relationship between the relative density and the speed of sound by taking a predetermined number of measurements over an initial relative density and a corresponding initial speed of sound in the gas,
- wherein said control means is programmed to measure the speed of sound in the gas, and
- wherein said control means is programmed to calculate the relative density of the gas from the linear relationship using the slope, the intercept and the corresponding measured speed of sound.
9 more elements
An apparatus for measuring a relative density of a gas, comprising:
- means for precalculating a slope and an intercept of a linear relationship between the relative density and a speed of sound;
- eans tor measuring the speed of sound in the gas;
- and
- means for calculating the relative density of the gas,
- wherein said apparatus is programmed to precalculate the slope and the intercept of the linear relationship between the relative density and the speed of sound by taking a predetermined number of measurements over an initial relative density and a corresponding initial speed of sound in the gas,
- wherein said apparatus is programmed to measure the speed of sound in the gas, and
- wherein said apparatus is programmed to calculate the relative density of the gas from the linear relationship using the slope, the intercept and the corresponding measured speed of sound.
4 more elements
A furnace comprising:
- means for receiving a supply of oxygen;
- means for receiving a supply of fuel gas;
- an oxygen/fuel gas ratio control system;
- control means for adjusting an oxygen/fuel gas ratio of gas fired process, comprising,
- means for precalculating a slope and an intercept of a linear relationship between a relative density and a speed of sound,
- means for measuring the speed of sound in the oxygen/fuel gas, and
- means for using a measured speed of sound for determining the relative density of a fuel gas for the gas fired process;
- and
- means for adjusting the oxygen/fuel gas ratio control system for the gas fired process in accordance with the determined relative density,
- wherein said control means is programmed to precalculate the slope and the intercept of the linear relationship between the relative density and the speed of sound by taking a predetermined number of measurements over an initial relative density and a corresponding initial speed of sound in the gas,
- wherein said control means is programmed to measure the speed of sound in the gas, and
- wherein said control means is programmed to calculate the relative density of the gas from the linear relationship using the slope, the intercept and the corresponding measured speed of sound.
9 more elements
A kiln comprising:
- means for receiving a supply of oxygen;
- means for receiving a supply of fuel gas;
- an oxygen/fuel gas ratio control system;
- control means for adjusting an oxygen/fuel gas ratio of a gas fired process, comprising,
- means for precalculating a slope and an intercept of a linear relationship between a relative density and a speed of sound,
- means for measuring the speed of sound in the oxygen/fuel gas, and
- means for using a measured speed of sound for determining the relative density of a fuel gas for the gas fired process;
- and
- means for adjusting an oxygen/fuel gas ratio control system for the gas fired process in accordance with the determined relative density,
- wherein said control means is programmed to precalculate the slope and the intercept of the linear relationship between the relative density and the speed of sound by taking a predetermined number of measurements over an initial relative density and a corresponding initial speed of sound in the gas,
- wherein said control means is programmed to measure the speed of sound in the gas, and
- wherein said control means is programmed to calculate the relative density of the gas from the linear relationship using the slope, the intercept and the corresponding measured speed of sound.
9 more elements
A compressor comprising:
- means for receiving a supply of oxygen;
- means for receiving a supply of fuel gas;
- an oxygen/fuel gas ratio control system;
- control means for adjusting an oxygen/fuel gas ratio of a gas fired process, comprising,
- means for precalculating a slope and an intercept of a linear relationship between a relative density and a speed of sound,
- means for measuring the speed of sound in the oxygen/fuel gas, and
- means for using a measured speed of sound for determining the relative density of a fuel gas for the gas fired process;
- and
- means for adjusting an oxygen/fuel gas ratio control system for the gas fired process in accordance with the determined relative density,
- wherein said control means is programmed to precalculate the slope and the intercept of the linear relationship between the relative density and the speed of sound by taking a predetermined number of measurements over an initial relative density and a corresponding initial speed of sound in the gas,
- wherein said control means is programmed to measure the speed of sound in the gas, and
- wherein said control means is programmed to calculate the relative density of the gas from the linear relationship using the slope, the intercept and the corresponding measured speed of sound.
9 more elements
Dependencies are inferred from the claim text.