US3752393A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital flow calculator
Assignee: TDY Industries LLC
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Filing: 1971-08-02
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Granted: 1973-08-14
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Expires: 1991-08-02
Abstract
Abstract A pre-programmed calculator illustrated by an embodiment which repeatedly solves expressions for determining the gas flow through an orifice in a pipeline, the calculator performing its calculations using digital techniques, and the measured flow parameters, including in this example the gas temperature, pressure, specific gravity and differential pressure across the orifice, all being changed to digital form prior to such calculations. Numerical constants used in the expressions being solved are inserted into the calculator in digital form by manually presettable switches. The gas flow calculated in standard cubic feet is subsequently converted to thousands of standard cubic feet and cumulatively displayed, and the remainder after each such conversion is added to the next calculated flow value prior to its conversion so that each remainder is preserved. The expression for gas flow which is solved by the present calculator is corrected by including a supercompressibility factor which is calculated anew during each new solution of the flow expression, and all calculations are repeated at a high rate to achieve high accuracy.
Inventors
- 👤 L Moseley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:55
CPC Classifications
G; G06; G06F; G06F7/00; G06F7/38; G06F7/48; G06F7/544; G01; G01F; G01F1/00; G01F1/05; G01F1/34; G01F1/50; G01F15/00; G01F15/02; G01F15/04; G01F15/043; G01F15/046; G06F7/60; G06F7/62
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
258 words
A digital calculator of the type including periodically repeating multiple-step program means sequentially actuating digital arithmetic means for calculating the flow of gas through an orifice based upon discretely sampled measurements of gas and flow parameters made in the vicinity of the orifice at the time of each new calculation by solving a flow expression including multiple separable mathematical terms including said parameters and empirical constants, the calculator comprising: a. gate means responsive to certain steps in said program for selectively entering sample measurement terms into the calculator as needed during calculations; b. analog to digital converter means coupled in series with said gate means and with an input bus of the arithmetic means; c. adjustable means for generating said empirical constant terms as digital numbers; d. gate means responsive to certain other steps in said program for selectively entering the constant terms at said input bus; and e. plural separate storage means in said calculator, said program means including a programmer operative to deliver outputs corresponding with its steps in a sequence thereby to enable said gate means and said arithmetic means to sequentially perform a sub-calculation on each one of said separable terms one at a time thereby to obTain corresponding digital numbers representing those sub-calculations and to temporarily enter those numbers in said storage means, and said programmer being operative to deliver subsequent steps in said sequence to retrieve from said storage means said subcalculation numbers and re-enter them into said arithmetic means and perform final calculations to complete the solving of said flow expression.
Claim 2
Dependent Claim
258 words
A digital calculator of the type including periodically repeating multiple-step program means sequentially actuating digital arithmetic means for calculating the flow of gas through an orifice based upon discretely sampled measurements of gas and flow parameters made in the vicinity of the orifice at the time of each new calculation by solving a flow expression including multiple separable mathematical terms including said parameters and empirical constants, the calculator comprising: a. gate means responsive to certain steps in said program for selectively entering sample measurement terms into the calculator as needed during calculations; b. analog to digital converter means coupled in series with said gate means and with an input bus of the arithmetic means; c. adjustable means for generating said empirical constant terms as digital numbers; d. gate means responsive to certain other steps in said program for selectively entering the constant terms at said input bus; and e. plural separate storage means in said calculator, said program means including a programmer operative to deliver outputs corresponding with its steps in a sequence thereby to enable said gate means and said arithmetic means to sequentially perform a sub-calculation on each one of said separable terms one at a time thereby to obTain corresponding digital numbers representing those sub-calculations and to temporarily enter those numbers in said storage means, and said programmer being operative to deliver subsequent steps in said sequence to retrieve from said storage means said subcalculation numbers and re-enter them into said arithmetic means and perform final calculations to complete the solving of said flow expression.
Claim 3
Dependent Claim
70 words
In a calculator as set forth in claim 1, said arithmetic means and said separate storage means having bit-capability including a predetermined number of bits, and said programmer including steps actuating said arithmetic means in a sequence operative to perform said sub-calculations upon terms of the expression which are selected such that the respective sub-calculations never result in numbers whose magnitudes exceed the bit-capability of the arithmetic and storage means.
Claim 4
Dependent Claim
121 words
In a calculator as set forth in claim 1, said calculator repeatedly solving said flow expression to determine cubic feet of gas flowing during the interval of the calculation; digital display means for displaying the quantity of gas calculated reduced by a scaling factor; means in the arithmetic means for repeatedly deducting said scaling factor from the calculated solution in cubic feet and incrementing said display means, and for entering the difference after each deduction into a remainder register; means operative after each calculation to test the difference to determine whether it has gone through zero; and means responsive to the difference going through zero to leave the next preceeding difference still in the remainder register and omit incrementing the display.
Claim 5
Dependent Claim
42 words
In a calculator as set forth in claim 3, said calculator including means operative after solving of said expression for adding the content of the remainder register to the solution of the expression before commencing the steps of deducting said scaling factor.
Claim 6
Dependent Claim
85 words
In a calculator as set forth in claim 1, said expression including a gas supercompressibility factor calculatable by solving a second expression having constant terms and variable terms including gas pressure and temperature and serving to compensate the flow expression for the difference in behavior between a perfect gas and the particular gas mixture passing the orifice, and said programmer including steps to actuate the arithmetic means to calculate the supercompressibility factor as one of said sub-calculations performed during each solution of the flow expression.
Claim 7
Independent Claim
219 words
The method of automatically calculating the flow of a gas mixture through an orifice using a fixed program controlling a digital calculator to solve an arithmetic expression having certain empirically determined pre-entered constants; including the steps of: a. measuring gas flow parameters including the pressure and temperature and specific gravity of the gas mixture approaching the orifice and including the differential pressure across the orifice; b. stepping the program through a sub-series of steps to actuate the calculator to perform a first sub-calculation based on measured parameters including the square root of the differential pressure divided by a term including the specific gravity multiplied by the temperature, and storing a first digital signal representing said first sub-calculation; c. stepping the program through a sub-series of steps to actuate the calculator to perform a second sub-calculation including the product of said first digital signal times a constant term representing the orifice constant, and storing a second digital signal representing said second sub-calculation; and d. stepping the program through a sub-series of steps to actuate the calculator to perform a third sub-calculation based on measured parameters comprising the square root of a term including the gas pressure and multiplying it by said second digital signal, and storing a third digital signal representing the gas flow and resulting from the third sub-calculation.
Claim 8
Independent Claim
219 words
The method of automatically calculating the flow of a gas mixture through an orifice using a fixed program controlling a digital calculator to solve an arithmetic expression having certain empirically determined pre-entered constants; including the steps of: a. measuring gas flow parameters including the pressure and temperature and specific gravity of the gas mixture approaching the orifice and including the differential pressure across the orifice; b. stepping the program through a sub-series of steps to actuate the calculator to perform a first sub-calculation based on measured parameters including the square root of the differential pressure divided by a term including the specific gravity multiplied by the temperature, and storing a first digital signal representing said first sub-calculation; c. stepping the program through a sub-series of steps to actuate the calculator to perform a second sub-calculation including the product of said first digital signal times a constant term representing the orifice constant, and storing a second digital signal representing said second sub-calculation; and d. stepping the program through a sub-series of steps to actuate the calculator to perform a third sub-calculation based on measured parameters comprising the square root of a term including the gas pressure and multiplying it by said second digital signal, and storing a third digital signal representing the gas flow and resulting from the third sub-calculation.
Claim 9
Dependent Claim
60 words
The Method as set forth in claim 6, including the steps of stepping the program through a sub-series of steps to actuate the calculator to determine a supercompressibility factor including a term comprising the gas pressure divided by a term including the temperature, and then multiplying the stored third sub-calculation by said supercompressibility factor to obtain a corrected gas flow.
Claim 10
Dependent Claim
70 words
The method as set forth in claim 6, including the steps of cyclically calculating said gas flow; dividing each calculated gas flow by a scaling factor; accumulating the number of times the scaling factor divides into each successively calculated gas flow; and preserving the remainder resulting from integral division by the scaling factor, and adding it to the next calculated gas flow before dividing the latter by said scaling factor.
Claim 11
Independent Claim
160 words
The method of determining the flow of a hydrocarbon gas mixture through an orifice, comprising the steps of measuring the pressure and temperature and specific gravity of the gas mixture approaching the orifice and the differential gas pressure across the orifice; automatically actuating a digital arithmetic calculator controlled by a fixed program to repeatedly calculate the solution of an empirical formula including the expression: Qh C'' . Fpv Square Root ( Delta P . Pf . 520)/(G(T+460)) where Qh is the flow of gas in cubic feet per hour, C'' is an orifice constant, Fpv is a supercompressibility factor, Pf is gas pressure within the range of zero to 1200 p.s.i., T is the gas temperature in the range of 30* to 120* F, G is the specific gravity ratio as compared to air and roughly falling between 0.58 and 0.68, and Delta P is the differential pressure across the orifice; and accumulating the gas flow Qh after each calculation.
Claim 12
Independent Claim
160 words
The method of determining the flow of a hydrocarbon gas mixture through an orifice, comprising the steps of measuring the pressure and temperature and specific gravity of the gas mixture approaching the orifice and the differential gas pressure across the orifice; automatically actuating a digital arithmetic calculator controlled by a fixed program to repeatedly calculate the solution of an empirical formula including the expression: Qh C'' . Fpv Square Root ( Delta P . Pf . 520)/(G(T+460)) where Qh is the flow of gas in cubic feet per hour, C'' is an orifice constant, Fpv is a supercompressibility factor, Pf is gas pressure within the range of zero to 1200 p.s.i., T is the gas temperature in the range of 30* to 120* F, G is the specific gravity ratio as compared to air and roughly falling between 0.58 and 0.68, and Delta P is the differential pressure across the orifice; and accumulating the gas flow Qh after each calculation.
Claim 13
Dependent Claim
33 words
In the method as set forth in claim 9, the step of calculating the supercompressibility factor Fpv during each new calculation of the gas flow Qh by solving the expression: Fpv 1+ (Pf)/(100(T+60))
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-13 | 1977-02-12 | 1977-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-13 | 1981-02-12 | 1981-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-13 | 1985-02-12 | 1985-08-14 | $7700.00 | Window Closed / Lapsed |