Showing papers on "Secondary air injection published in 1975"

Air-atomizing fuel nozzle

Abstract: A fuel injection nozzle for gas turbines in which atomization of the liquid fuel is accomplished by high-velocity air entering the combustion chamber, characterized by minimizing the surface area of metal in contact with the fuel during the atomization process and further characterized by designing the air passages such that a swirling motion is imparted to the air followed by an acceleration of the air stream to eliminate variations in air velocity and to maximize air velocity at the point of impact with the fuel.

Apparatus for and method of suppressing infrared radiation emitted from gas turbine engine

Abstract: An apparatus for and method of suppressing infrared radiation emitted from hot metal parts at the aft end of a gas turbine engine and from the exhaust gas plume thereof is provided and such apparatus comprises a dual purpose ejector vane assembly operatively attached to the engine for introducing cooling ambient air into the hot engine exhaust gases and hiding the hot metal parts. The vane assembly has a duct structure for receiving and confining the engine exhaust gases and the assembly provides at least one stream of cooling ambient air across one full dimension of the duct structure and exhaust gases confined thereby with the stream of cooling ambient air mixing with the hot engine exhaust gases across the full dimension of the duct structure to assure optimum mixing thereof.

Engine with dual sensor closed loop fuel control

Abstract: In a closed loop fuel control system for an internal combustion engine having a catalytic converter in its exhaust system, a first zirconia sensor in the exhaust system upstream from the catalytic converter generates a signal indicative of air-fuel ratio in gases before catalytic treatment, a second zirconia sensor in the exhaust system downstream from the catalytic converter generates a signal indicative of air-fuel ratio in gases after catalytic treatment and a cascade feedback control system including both zirconia sensors controls the rate of flow of fuel or air to the engine in response to both sensor signals and a reference to maintain a constant stoichiometric air-fuel ratio in the exhaust system for maximum catalytic converter efficiency in simultaneous oxidation and reduction. The engine fuel system reverts to open loop operation during wide open throttle, closed throttle and cold start operation.

Effects of Equivalence Ratio and Dwell Time on Exhaust Emissions From an Experimental Premixing Prevaporizing Burner

Abstract: A flame-tube study was performed to determine the effects of equivalence ratio and residence time on exhaust emissions with premixed, prevaporized propane fuel. Nitrogen oxides emissions as low as .3 g NO2/kg fuel were measured with greater than 99% combustion efficiency at 800 K inlet temperature and an equivalence ratio of .4. For a constant combustion efficiency, lower nitrogen oxides emissions were obtained by burning very lean with relatively long residence times than by using somewhat higher equivalence ratios with shorter times.

Combined fuel injection and intake valve for electronic fuel injection engine systems

Abstract: A solenoid actuated combined fuel injection and intake valve supplies an air-fuel mixture to an electronic fuel injection system for an internal combustion engine. In one embodiment of the invention fuel injection is controlled dependent upon the operation of an auxiliary air-fuel intake valve while in another embodiment of the invention fuel injection is controlled independent of the operation of the auxiliary valve.

Building fresh air ventilator system

Abstract: A fresh air ventilator system for a building or the like having a conditioned air plenum and a return air aperture communicating interiorly of the building, respectively, for circulation of conditioned air within the building, characterized by a ventilator unit disposed in a weather-proof cabinet on a sealing roof curb on the roof of the building. The ventilator unit includes a fresh air inlet adapted to admit fresh air and exclude precipitation and having a fresh air damper for controlling the quantity of fresh air from zero to the maximum; an air circulating blower suitably connected to effect circulation of air through the building; an exhaust means for at least periodically exhausting a portion of the return air; a proportioning damper disposed at the return air aperture for proportioning the amount of return air, from zero to the maximum, fed to the circulating blower; and air conditioning means for conditioning the air to be circulated. Also disclosed are specific preferred structural embodiments, controls, modes and operations; for example, the fresh air inlets, the return air exhaust means, the disposition of the condenser passageway and fan with respect to the fresh air inlet, and the splitter arrangement of the proportioning damper between circulated air and exhaust.

Closed loop fuel control using air injection in open loop modes

Abstract: A fuel control for an engine is normally operated closed loop with a feedback signal from an air-fuel ratio sensor in the engine exhaust. However, during idle, wide open throttle and engine warm up operating modes, the closed loop control is cut out and the engine is run rich with air injected into the exhaust system to reduce carbon monoxide and hydrocarbon emissions.

Fuel injection system controlling air/fuel ratio by intake manifold gas sensor

Abstract: In a fuel injection system for an internal combustion engine, a gas sensor is positioned in the intake manifold and is responsive to a characteristic of the air mixture entering the intake manifold to generate electrical control signals for controlling the injecting of the fuel to the engine In the preferred embodiment, the air and the recirculated exhaust gas (EGR) are mixed together in a throttle body and the resultant mixture passes by the gas sensor prior to being distributed throughout the manifold system The output signal of the sensor is used in controlling the injection time of the fuel injectors Fuel delivery correction delays due to transport lag in conventional closed loop fuel injection systems using oxygen gas sensors placed in the exhaust system are greatly minimized

Burner control system

Abstract: A burner control system for improving burner performance and efficiency. The system may determine fuel and air channel or manifold parameters. Determination of parameters may be performed with a sensor connected across the air and fuel channels. A signal from the sensor may control the parameters which in turn affect the amounts of fuel and air to the burner via a controller. Parameter control of the fuel and air in their respective channels may result in more accurate fuel and air ratio control. One or more flow restrictors in fuel and/or air bypass channels may further improve accuracy of the fuel and air ratio. The channels may be interconnected with a pressure or flow divider. Byproducts of combustion in the exhaust, temperatures of gas and air, flame quality and/or other items may be monitored and adjusted with control of the fuel and air ratio for optimum combustion in the burner.

Effect of hydrogen injection stability and emissions of an experimental premixed prevaporized propane burner

Abstract: Hydrogen in quantities up to 5 percent by weight of the total fuel flow was injected into a premixed propane burner. The hydrogen was either premixed with the propane and air upstream of the burner or introduced as a torch at the flameholder. Emissions of total nitrogen oxides, carbon monoxide, and unburned hydrocarbon are reported as are combustion efficiencies and lean blowout limits. To maintain at least 99 percent combustion efficiency at a 700 K inlet mixture temperature with no hydrogen added, it was necessary to burn with a propane equivalence ratio of 0.525. When 4 percent hydrogen was premixed with the propane and air, a combustion efficiency greater than 99 percent was recorded at a propane equivalence ratio of 0.425. The total nitrogen oxides (NOx) emissions corresponding to these two conditions were 0.8 g NO2/kg equivalent propane and 0.44 g NO2/kg equivalent propane, respectively. The hydrogen torch did not reduce NOx emissions.

Engine secondary air flow control system

Abstract: An engine has an air injection system injecting air into the exhaust system to reduce emissions. The injection is scheduled by a bypass valve that normally permits injection, but bypasses or dumps the air as a function of a carburetor ported vacuum signal that is also used to control exhaust gas recirculation. A control is provided to maintain air injection for a short period during certain engine idle conditions, but dumping of the air after this period. An engine deceleration override is provided to dump the air when this condition exists, to prevent backfire. A cold engine vacuum lock-out also is provided.

Fuel injection timing control system for internal combustion engine

Abstract: A fuel injection timing control system is provided wherein a fluid actuator having a fluid chamber containing therein a movable wall member and the amount of pressure medium in the fluid chamber are controlled by electromagnetically operated control valve means to cause the actuator to operate an element for controlling the fuel injection timing of a fuel injection pump. In the control system of this invention, a control voltage is produced from at least a speed signal corresponding to the rotational speed of an engine and a fuel injection quantity signal corresponding to the amount of fuel injected into the engine from a fuel injection pump, and this control voltage is compared with a injection timing voltage corresponding to the fuel injection timing of the fuel injection pump to produce a deviation signal which is used to actuate the electromagnetically operated control valve means so as to automatically control the fuel injection timing of the injection pump and thereby to obtain the optimum injection timing that suits the varying operating conditions of the engine.

Exhaust gas recirculation system with control apparatus for exhaust gas flow control valve

Abstract: An exhaust gas recirculation system comprises an exhaust gas flow control valve; a vacuum actuator for operation of the flow control valve; and a control apparatus for the vacuum actuator. The control apparatus comprises a vacuum regulator and a vacuum motor for actuating the vacuum regulator in response not only to the venturi vacuum but also to the intake manifold vacuum.

Exhaust system for multi-cylinder internal combustion

Abstract: An exhaust system for multi-cylinder internal combustion engines, which is directed to the so-called proportional exhaust gas recirculation (EGR) for improving engine exhausts. The system comprises an exhaust gas recirculating circuit connected to one engine cylinder for recirculating to an intake pipe of the engine the entire amount of exhaust gas which is discharged from said one engine cylinder. Switching means is provided in said exhaust gas recirculating circuit for switching the flow of the recirculating exhaust gas in response to a value of a predetermined parameter indicating particular operating conditions of said engine. Heat exchanging means is provided in said exhaust gas recirculating circuit in contact with said intake pipe of the engine for heating said intake pipe by heat exchange with hot exhaust gas flowing through said exhaust gas recirculating circuit, and a reactor is provided in the exhaust pipe of the engine for receiving for cleaning purposes the entire amount of exhaust gases which are discharged from engine cylinders other than said one engine cylinder.

Electronically controlled exhaust gas purifying system

Abstract: An electronically controlled exhaust gas purifying system for use with an internal combustion engine of a motor vehicle including not only a catalytic converter but also an auxiliary thermal reactor which is located upstream of the catalytic converter and by which exhaust gases emitted from the engine is re-combusted to the extent that the catalytic converter is not destroyed or damaged by the residual unconsumed compounds in exhaust gases discharged from the thermal reactor. The system is provided with an electronic control means for shutting off the flow of secondary air to be mixed with the exhaust gases emitted from the engine both when at least one of the temperatures of the catalytic converter and the thermal reactor rises above a critical value at which they would be destroyed or damaged, and when the engine is under cranking operation. The electronic control means retards the spark in order to heat the exhaust gases when the temperature of the reactor falls to its reaction commencement temperature. In the event that the rate of temperature rise of the thermal reactor exceeds a threshold value, the electronic control means does not retard the spark even if the temperature of the thermal reactor falls to the reaction commencement temperature, but then retards the spark when the temperature of the thermal reactor falls below a predetermined value which is set lower than that of the reaction commencement temperature.

Injection installation for diesel internal combustion engine

Abstract: An injection system for a Diesel internal combustion engine which includes an injection pump with injection lines, injection valves with valve needles opening inwardly against spring pressure and leakage oil lines starting from the injection valve; a device consisting of a flow-direction sensor detecting the direction of flow and of a discharge valve is thereby arranged in each injection line, preferably in proximity of the injection valve, which discharges the pump volume of the injection valve resulting at the end of the injection operation into the leakage oil line.

Apparatus for mounting exhaust gas sensor

Abstract: Herein disclosed is an apparatus by which an exhaust gas sensor is placed in flow communication with the exhaust gases issued from an engine. The apparatus is so constructed and arranged such that a volume of air is maintained about a body portion of the exhaust gas sensor in heat conductive relation with the exhaust gases. The apparatus may be provided with a heater around a probe portion of the exhaust gas sensor which projects into the exhaust conduit. The heater is selectively energized to heat the probe portion when the temperature of the exhaust gases is low.

Internal combustion engine exhaust emission control

Abstract: A V-type internal combustion engine has left and right exhaust manifolds interconnected by an exhaust crossover passage and connected by left and right exhaust pipes respectively to a main catalytic converter. The left exhaust pipe has an auxiliary catalytic converter, while the right exhaust pipe has a valve which is closed during engine warm-up. The valve diverts exhaust gases from the right exhaust manifold through the crossover passage to the left exhaust manifold for flow through the auxiliary converter and the left exhaust pipe to the main converter during warm-up and permits exhaust gases to flow directly from the right exhaust manifold to the main converter during normal operation. A pump delivers air into the right exhaust manifold for delivery through the auxiliary converter to the main converter during engine warm-up and for delivery directly to the main converter during normal operation, thus limiting oxidation in the auxiliary converter.

Control system for promoting catalytic removal of noxious components from exhaust gas of internal combustion engine

Abstract: With respect to an internal combustion engine equipped with a carburetor and a catalytic converter which requires to feed the engine with a stoichiometric air/fuel mixture, the control system is for regulating the air/fuel ratio produced in the carburetor and comprises an auxiliary air admitting passage connected to the fuel discharge passage of the carburetor in addition to a usual air bleed passage for the fuel discharge passage, an electromagnetic valve for controlling the admission of air into the auxiliary passage, an oxygen sensor disposed in the exhaust system upstream of the catalytic converter, and a control circuit for producing continual pulses at a frequency between 5 and 100 Hz. The widths of the individual pulses are increased gradually while the output of the oxygen sensor indicates the air/fuel ratio being below the stoichiometric ratio, and vice versa. The valve is opened as each pulse is applied thereto so that the air feed rate to the fuel in the fuel passage is momentarily augmented by admission of air into the auxiliary passage.

Electronic fuel injection apparatus

Abstract: A fuel injector for injecting fuel by reading the stored information on the predetermined amount of fuel in accordance with the throttle opening and engine revolutions, is provided with an acceleration detector and an acceleration corrector adapted for purification of exhaust gas and fuel injection in conformity with the engine operating conditions.

Metering control for the air-fuel mixture in internal combustion engines

Abstract: A fuel injection control system for an internal combustion engine comprises at least one auxiliary air supply branched at the engine intake pipe downstream of the air-fuel metering system, and at least one valve controlling the auxiliary air supply. The valve is controlled by a diaphragm with a return-spring membrane subjected to a partial vacuum from any suitable source which is modulated on one hand by at least one variable throttle or choke responsive to the air flow in the metering system and, on the other hand, by an electronic valve controlled by a probe responsive to the composition of burnt gases in the exhaust manifold.

Overheating protection for an exhaust gas purification block

Abstract: A method and apparatus for preventing an overheating of an exhaust gas purification block for internal combustion engines in case of a high proportion of combustible gas components in the exhaust gases, in which the exhaust gases are adapted to be conducted past the exhaust gas purification block by way of a controllable by-pass line; at least during the periods when the by-pass line is opened, air preferably in the form of an air jet directed opposite to the normal exhaust gas flow is blown into the line leading into the exhaust gas purification block whereby preferably the air jet passes over the inlet opening of the exhaust gas purification block in a transverse direction.

Heat insulating apparatus for exhaust pipe of an internal combustion engine

Abstract: Heat insulating apparatus for an exhaust pipe of an internal combustion engine to maintain exhaust gases at high temperature to reduce unburned constituents. The apparatus is so arranged as to permit the thermal expansion of the exhaust pipe. The exhaust pipe is located with a heat insulating material which in turn is coated with a cover. One end of the cover is secured to the exhaust pipe and the other end is slidably engaged with the exhaust pipe.

Process and system for detoxicating the exhaust gases of an internal combustion engine

Abstract: For detoxicating the exhaust gases of an internal combustion engine an in-series arrangement of a first reactor and an oxidizing reactor is provided with the exhaust line of the engine along with an oxygen measuring element and structure for producing two additional air streams fed to the exhaust line The first reactor reduces the nitrogen oxides in the exhaust gas and the second or oxidizing reactor oxidizes the hydrocarbons and the carbon monoxide in the exhaust gas The oxygen measuring element is mounted to the exhaust line and regulates the mass ratio of air to fuel on the suction side of the engine The first additional air stream is injected into the exhaust pipe in the flow direction upstream of the oxygen measuring element The quantity of this air stream is regulated and corresponds to the fuel throughput of the engine so that when the oxygen measuring element measures a stoichiometric mixture (λ=1) a slightly rich air-fuel mixture (λ ≈098-099) is supplied to the engine BACKGROUND OF THE INVENTION The present invention relates to a process and system for detoxicating the exhaust gases of an internal combustion engine, the exhaust pipe of which contains an in-series arrangement of a first reactor for reducing the nitrogen oxides in the exhaust and a second reactor for oxidizing the hydrocarbons and the carbon monoxide in the exhaust This process operates with a first control system which regulates the mass ratio of air to fuel on the intake side of the engine as a function of the quantity measured by an oxygen measuring element disposed in the exhaust pipe and with at least a second control system which controls the injection of supplementary air into the exhaust pipe in the direction of flow upstream of the oxidizing reactor With exhaust gas detoxicating systems of this type comprising two bed catalysts, to obtain satisfactory reduction of the nitrogen oxides NOx, the air-fuel mixture supplied to the engine should be slightly richer (λ<1) than a stoichiometric mixture (λ= 1) By using this slightly richer mixture (slight air deficiency), the combustion temperature in the engine is kept relatively low which counteracts oxygen formation and provides a better drive performance as less misfiring and other disturbing phenomena are produced in the course of combustion when the position of the accelerator is altered rapidly This slightly richer mixture can be ignited more easily On the other hand, this produces an increase of carbon monoxide CO and hydrocarbons HC These substances are thereafter oxidized in the oxidizing catalyst while air is added The slightly richer mixture is also an advantage to the rapid heating of the oxidizing catalysts as these only operate satisfactorily after reaching a specific operating temperature which is largely dependent on the composition of the catalysts Known detoxicating processes of the type described initially operate with a relatively rich air-fuel mixture on the intake side of the engine so that with the constantly varying characteristic values of the engine during operation of an internal combustion engine, it is possible to effectively prevent the engine from occasionally receiving too lean a fuel mixture, resulting in that the additional CO required of reducing NOx is not present The disadvantage of these known systems is a relatively large, costly air pump for injecting large quantities of additional air into the exhaust pipe, a high efficiency loss and high fuel consumption OBJECTS AND SUMMARY OF THE INVENTION The principal object of the present invention is to provide a detoxicating system of the type described initially by means of which a slightly richer air-fuel mixture (λ = 098 - 099) is supplied to the engine, wherein measurements taken on the exhaust side of the engine are effected by an oxygen measuring element which changes its output voltage abruptly, in a manner known per se, when the air number λ = 1, such that only this air number is utilized for an accurate measurement, and wherein the supplementary air is supplied by a relatively small pump This and other objects are accomplished according to the present invention in that the supplementary air supply is divided into two streams and blown into the exhaust pipe, with a first stream being injected in the direction of flow upstream of the oxygen measuring element and being regulated at a quantity corresponding to the gas throughput of the engine so that with a measuring element measurement of a stoichiometric mixture (λ = 1), a slightly richer air-fuel mixture (λ ≈ 098 - 099) is supplied to the engine, and with a partial stream of additional air being supplied upstream of the oxygen measuring element, such that a slightly weaker air-fuel mixture is initially detected by the measuring element Thus, a slightly richer air-fuel mixture is supplied to the engine in correspondence with the first partial stream of additional air Although the fuel consumption is only slightly higher than when λ = 1, a reducing or oxidizing atmosphere will be sure to prevail in the catalysts According to a feature of the invention, the supplementary air pump is driven by the engine and the first partial stream of supplementary air can be controlled, at least indirectly, in dependence on the pressure in the suction pipe downstream of the engine throttle valve According to another feature of the invention the partial stream of additional air is regulatable as a function of the flow conditions in the exhaust line Other objects, features and advantages of the present invention will be made apparent from the following detailed description of two preferred embodiments thereof provided with reference to the accompanying drawings which show three variants of the two embodiments

Method and apparatus for the automatic control of the air ratio of a combustion process

Abstract: A method for automatically controlling the air ratio of a combustion process by adjustment of the fuel-air mixture as function of the air number, the air number of the exhaust gas being measured with a sensor which is particularly sensitive at an air number of a given magnitude, and the combustion process operating with an air ratio having an air number of a different magnitude out of the sensitivity range of the sensor which includes extracting a hot exhaust gas stream from a combustion process having an air ratio with an air number out of the given sensitivity range of a sensor changing the amount of air in the exhaust gas stream to provide an auxiliary gas stream having an air number in the sensitivity range of the sensor, measuring the air number of the auxiliary gas stream to detect the difference from the air number of the given magnitude, and controlling the air ratio of the combustion process to maintain the air number of the auxiliary gas stream at the given magnitude, and apparatus for carrying out the foregoing method.

Exhaust gas passage of internal combustion engine

Abstract: PURPOSE: To attempt a power-up by maintaining on a substantially equal level of heat insualting functionof an exhaust gas passage of a siamese-type effective for improving exhaust gas purification and by preventing exhaust gas interruption. COPYRIGHT: (C)1977,JPO&Japio

Manifold system for an internal combustion engine

Abstract: An intake and exhaust system for an internal combustion engine of the type having an auxiliary combustion chamber associated with each main combustion chamber, and wherein the overall air-fuel charge to all combustion chambers is leaner than the stoichiometric ratio, so that excess air is present in the exhaust gases. The system includes integrated intake manifolds, one for connection with the main combustion chamber and the other for connection with the auxiliary combustion chamber, and an exhaust manifold for connection with the main combustion chambers. The exhaust manifold includes a stainless steel liner enveloped within and spaced from a metal casting in order to retain the heat of the exhaust gases so that the exhaust gas temperature remains at or above the temperature at which the unburned hydrocarbons in the exhaust gases will continue to burn. This temperature also promotes oxidation of carbon monoxide to carbon dioxide. The intake manifold is in thermal association with the exhaust manifold to provide a transfer of heat from the exhaust manifold to the intake manifold so that a rich mixture for the auxiliary combustion chambers and a lean mixture for the main combustion chambers are both heated in a controlled ratio. An integral heat riser member is positioned between the exhaust manifold and the intake manifold for transferring heat therebetween. The liner has a collection chamber with a baffle located therein to direct the flow of exhaust gases to insure proper heat transfer to the riser member. Another main feature of the system is to present a minimum heat capacity in association with the exhausting gases to allow the overall system to quickly achieve preferred operating conditions.

Air classification apparatus

Abstract: A rotary drum air classifier system which includes a side feed hopper by which mixed materials to be separated are fed to a screw feed which deposits the materials inside the drum for major separation into light and heavy materials, the screw feed being longitudinally adjustable and including air injection means for fluidizing the mixed materials as they are being transported to the drum and thus accomplishing a preliminary stage of air classification during the time the mixed materials are transiting the length of the feed screw.