Showing papers on "Reciprocating engine published in 1972"
Patent•
21 Aug 1972TL;DR: In this paper, the authors described a multi-cylinder four-stroke cycle reciprocating engine with a compression ratio of 8 to 1 and a fuel-rich mixtures of about 10 to 1 air-fuel ratio.
Abstract: Expansible chamber engine arrangements and operating methods for staged combustion to obtain low emissions of unburned hydrocarbons, carbon monoxide and nitrogen oxides. In a preferred form described in the specification, the engine is a multicylinder four-stroke cycle reciprocating engine, such as a V-8 engine, having about 8 to 1 compression ratio. Two cylinders of each bank serve as first stage combustion chambers, and discharge into an interstage manifold for that bank. The two separate interstage manifolds communicate, respectively, with the intakes of the two other cylinders of the same bank, which serve as second stage combustion chambers. Also, in accordance with a preferred form of the invention, fuel-rich mixtures of about 10 to 1 air-fuel ratio are burned in the first stage cylinders yielding partially burned combustion products and noncombustibles with minimum nitrogen oxides. Air is added to these interstage exhaust gases to provide dilute mixtures with a slightly lean overall air-fuel ratio of about 15 to 1. These mixtures are burned to substantial completion in the second stage cylinders to produce engine exhaust gases containing very small amounts of unburned hydrocarbons, carbon monoxide and nitrogen oxides. Further, in a preferred form of the invention, both first and second stage cylinders operate on the four-stroke cycle and both contribute substantially to the net mechanical energy developed by the engine. The rich air-fuel mixtures supplied the first stage cylinders are preferably spark-ignited in conventional manner while the slightly lean and highly diluted mixtures supplied the second stage cylinders are compression ignited, selection of the content and temperature of the second stage mixtures, compression pressures and other parameters providing ignition near the end of the compression stroke.
48 citations
Patent•
12 Dec 1972
TL;DR: In this article, a ratchet-type reciprocating engine barring tool is described, which includes a multiposition, multiangular extension handle, tapered ratchet handle, ratchet head assembly, double tooth dog holding action and a capability for clockwise and counter-clockwise operation by a single unaided person.
Abstract: This invention concerns a ratchet-type reciprocating engine barring tool. The tool design includes a multi-position, multiangular extension handle, tapered ratchet handle, ratchet head assembly, double tooth dog holding action and a capability for clockwise and counter-clockwise operation by a single unaided person.
48 citations
1 Feb 1972
15 citations
Patent•
16 Feb 1972TL;DR: A thermodynamic reciprocating engine in combination with a carburetor having inlets and control apparatus responsive to air and fuel flow for providing optimum operation is proposed in this article, where the authors show that it is possible to achieve high performance with a small number of inlets.
Abstract: A thermodynamic reciprocating engine in combination with a carburetor having inlets and control apparatus responsive to air and fuel flow for providing optimum operation.
9 citations
TL;DR: Emission-absorption techniques in both the ultraviolet and infrared regions of the spectrum were used to measure the temperature of combustion gases in the cylinder of an operating reciprocating engine.
7 citations
1 Jan 1972
TL;DR: In this article, the effect of lower order external excitations on the characteristics of the motion of a reciprocating engine has been investigated and compared with solutions of the equation obtained from an analogue computer.
Abstract: The analysis of torsional vibrations in the running gear of reciprocating engine systems is normally carried out by neglecting the variation in inertia torques of the system arising from the motion of the reciprocating parts. When the variable inertia effect is allowed for the equation of motion taking into account the effect is non-linear. Assuming small displacements, the equation can be linearized to predict important characteristics of the motion. Such an equation when solved by numerical methods using a digital computer predicts the regions of instability and the manner in which the amplitude and frequency vary with the speed of rotation of the engine. The responses of the system show a modulation of amplitude and frequency at definite rotational speeds. The occurrence of such a modulation in amplitude and frequency is established by use of the process given by Wentzel, Kramers, Brillouin and Jeffreys generally known as the WKBJ approximation. The first order term in the equation and the forcing term which represents the outer impulse from the reciprocating parts, are investigated for their effect on the waveforms of the responses of the system. Futher investigations of the effect of lower order external excitations on the characteristics of the motion are given. Theoretical results are compared with solutions of the equation obtained from an analogue computer. A discussion of some actual cases from engines in service is included.
6 citations
Dissertation•
1 Jan 1972
TL;DR: In this paper, the effect of external excitations on the characteristics of the motion of a reciprocating engine was investigated and the results were compared with solutions of the equation obtained from an analogue computer.
Abstract: The analysis of torsional vibrations in the running gear of reciprocating engine systems is normally carried out by neglecting the variation in inertia torques of the system arising from the motion of the reciprocating parts. When the variable inertia effect is allowed for the equation of motion taking into account the effect is non-linear. Assuming small displacements, the equation can be linearized to predict important characteristics of the motion. Such an equation when solved by numerical methods using a digital computer predicts the regions of instability and the manner in which the amplitude and frequency vary with the speed of rotation of the engine. The responses of the system show a modulation of amplitude and frequency at definite rotational speeds. The occurrence of such a modulation in amplitude and frequency is established by use of the process given by Wentzel, Kramers, Brillouin, and Jeffreys generally known as the WKBJ approximation. The method of variation of parameters and the WKBJ approximation are used to determine the time responses of the system as an independent verification of the numerical methods although this method is applicable only in a limited range of the engine speed for the specific ratio of the equivalent inertia of the reciprocating parts to the total equivalent inertia of the system. The first order term in the equation, the forcing term which represents the outer impulse from the reciprocating parts and the variable part of the elastic term are investigated for their effect on the waveforms of the responses of the system. Further investigations of the effect of external excitations on the characteristics of the motion are carried out which explain the cause of failure in some multi-cylinder engines due to secondary resonance. Various other characteristics of the variable inertia system and the complete solutions of the equation of motion including damping are explored in the present work. Theoretical results are compared with solutions of the equation obtained from an analogue computer. A discussion of results obtained by measurements on an engine in service with suspected secondary resonance and some actual cases of crankshaft failures in practice is included.
1 citations
Patent•
2 Oct 1972
TL;DR: An internal combustion reciprocating engine having a highly transparent window replacing the head or a portion thereof provides a modulated infrared radiation source whereby the radiation from the combustion gases passing through the window is essentially fully modulated at varying frequencies as discussed by the authors.
Abstract: An internal combustion reciprocating engine having a highly transparent window replacing the head or a portion thereof provides a modulated infrared radiation source whereby the radiation from the combustion gases passing through the window is essentially fully modulated at varying frequencies.