Patent US3817100A successfully refreshed from Google Patents.
US3817100A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Critical flow venturi
Assignee: Ford Motor Co
•
Filing: 1972-11-03
•
Granted: 1974-06-18
•
Expires: 1992-11-03
Abstract
Abstract An apparatus for determining the total mass of exhaust gas constituents emitted from an internal or external combustion engine, the apparatus having a through-flow duct to receive the exhaust gases and into which is introduced dilution air for thorough mixing with the exhaust gases. The apparatus has means for measuring not only the total mixed flow but also the total flow of dilution air introduced to the duct. Unique means is utilized for extracting and measuring a proportional sample of said mixed flow. Collection and measuring apparatus is used to determine the concentration of dilution air constituents as well as the combined concentration of gaseous constituents in the mixed flow. Utilizing the above two flow measurements and the two constituent concentration measurements, the total mass of exhaust gas from the engine is simply determined on a theoretically correct basis.
Inventors
- 👤 R Anderson
- 👤 N Azelborn
- 👤 W Wade
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:55
CPC Classifications
G; G01; G01F; G01F1/00; G01N; G01N1/00; G01N1/02; G01N1/22; G01N1/2247; G01N1/2252; G01N1/24; G01N2001/2264; G01N2001/242; G01N2001/244
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
191 words
In an apparatus useful in determining the total mass of exhaust gas constituents emitted from an engine, the apparatus having a through-flow duct to receive the exhaust gases and into which is introduced dilution air in a manner to mix with the exhaust gases, the apparatus having means for measuring the total mixed flow and having means for measuring the concentration of constituents, an improvement in said apparatus comprising: a. means for extracting and measuring a truly proportional sample of said mixed flow for determining the combined concentration of gaseous constituents in said mixed flow, b. means for measuring the total flow of dilution air introduced to said duct, whereby a determination of the mass of gaseous constituents emitted by said engine for a predetermined period will be obtained by taking the product of the mixed flow, constituent concentration in the mixed flow, and the constituent density, and then subtracting the product of dilution air flow, constituent concentration in said dilution air flow, and the constituent density, said determination being independent of variations in the flow rate, flow temperature or flow pressure in either of said dilution air or exhaust gases.
Claim 2
Dependent Claim
191 words
In an apparatus useful in determining the total mass of exhaust gas constituents emitted from an engine, the apparatus having a through-flow duct to receive the exhaust gases and into which is introduced dilution air in a manner to mix with the exhaust gases, the apparatus having means for measuring the total mixed flow and having means for measuring the concentration of constituents, an improvement in said apparatus comprising: a. means for extracting and measuring a truly proportional sample of said mixed flow for determining the combined concentration of gaseous constituents in said mixed flow, b. means for measuring the total flow of dilution air introduced to said duct, whereby a determination of the mass of gaseous constituents emitted by said engine for a predetermined period will be obtained by taking the product of the mixed flow, constituent concentration in the mixed flow, and the constituent density, and then subtracting the product of dilution air flow, constituent concentration in said dilution air flow, and the constituent density, said determination being independent of variations in the flow rate, flow temperature or flow pressure in either of said dilution air or exhaust gases.
Claim 3
Dependent Claim
76 words
The improvement of claim 1, in which the proportional measuring means comprises: a. a flow restriction in said duct, b. drive means for drawing said mixed flow through said restriction at a rate effective to achieve at least a substantially choked flow condition, and c. a sampling passage for extracting a proportional quantity of mixed flow from said duct and having an inlet disposed in a region of said duct where substantially choked flow conditions exist.
Claim 4
Dependent Claim
39 words
The improvement as in claim 2, in which the means for measuring dilution air flow comprises a protuberance interposed in the dilution air flow and a sensing mechanism for determining the degree of flow vortex shed by said protuberance.
Claim 5
Dependent Claim
67 words
The improvement as in claim 2, in which the means for measuring dilution air flow comprises a venturi restriction operating upon said dilution air flow and having a throat area of sufficient size to provide for continuous unchoked flow therethrough, and a sensing mechanism for determining the degree of potential energy converted to kinetic energy bY the venturi restriction thereby providing for determination of the flow therethrough.
Claim 6
Dependent Claim
27 words
The improvement as in claim 1, in which said through-flow duct is arranged to convey mixed flow at a rate no less than 1.5 lbs. per second.
Claim 7
Dependent Claim
43 words
The improvement as in claim 2, in which said sampling passage additionally contains a second restriction, and means for drawing sampled flow through said second restriction at a rate to achieve substantially choked flow conditions, said first and second restrictions being in parallel.
Claim 8
Dependent Claim
105 words
The improvement as in claim 1, in which said apparatus has a fuel measuring means substituted for the measuring means of the total mixed flow passing through said duct, whereby the mass of an exhaust gas constituent can be computed by determining the constituent concentration from said proportional measuring means, ratioing the resultant to the sum of all carbon-containing constituent concentrations, and multiplying said ratio by the total fuel consumed, specific gravity of fuel, and by the ratio of the molecular weights of the constituent to fuel, and then subtracting the mass of the constituent contained dilution air as calculated by the same mathematical procedure.
Claim 9
Independent Claim
224 words
A system for measuring the total mass of certain gaseous constituents emitted by a gas turbine engine during a predetermined test cycle, the system comprising: a. a through-flow duct effective to receive all exhaust gases emitted by said engine, b. a dilution air passage effective to introduce a variable amount of dilution air into said duct as required by the flow conditions in said duct, c. means in said duct for homogeneously mixing said dilution air and exhaust gases, d. a pair of parallel arranged venturi restrictions in said duct, one located so as to operate upon said total mixed flow for converting a portion of the flow potential energy to kinetic energy, and the other located so as to operate upon a sample of said mixed flow no greater than 2 percent thereof, each venturi restriction having a flow entrance arranged and related to the other so as to obtain accurate proportionality between the respective flows passing therethrough, e. means to maintain a choked flow condition through each of said venturi restrictions, f. means for measuring the total flow of each of said dilution air and said mixed flow for said test cycle, g. means for determining the concentration of a selected gaseous constituent present in the flow passing through said sampling restriction and in the dilution air flow introduced through said duct.
Claim 10
Independent Claim
224 words
A system for measuring the total mass of certain gaseous constituents emitted by a gas turbine engine during a predetermined test cycle, the system comprising: a. a through-flow duct effective to receive all exhaust gases emitted by said engine, b. a dilution air passage effective to introduce a variable amount of dilution air into said duct as required by the flow conditions in said duct, c. means in said duct for homogeneously mixing said dilution air and exhaust gases, d. a pair of parallel arranged venturi restrictions in said duct, one located so as to operate upon said total mixed flow for converting a portion of the flow potential energy to kinetic energy, and the other located so as to operate upon a sample of said mixed flow no greater than 2 percent thereof, each venturi restriction having a flow entrance arranged and related to the other so as to obtain accurate proportionality between the respective flows passing therethrough, e. means to maintain a choked flow condition through each of said venturi restrictions, f. means for measuring the total flow of each of said dilution air and said mixed flow for said test cycle, g. means for determining the concentration of a selected gaseous constituent present in the flow passing through said sampling restriction and in the dilution air flow introduced through said duct.
References Cited (Backward Citations)
US3603155A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |