Showing papers on "Diesel engine published in 1968"

Method of controlling pipeline slurries

Abstract: 1,253,445. Automatic control of slurry concentration. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N. V. Feb. 20, 1969 [Feb. 23, 19681 No. 9170/69. Heading G3R. In a system for pumping slurry through a pipeline at the minimum stable velocity, the speed of a pump is automatically controlled in dependence on any difference between measured spatial and transport concentrations of the solid particles. As shown a slurry is pumped through a pipeline 10 by a pump 16 driven by a diesel engine 90. A densitometer 30 e. g. of the gamma radiation type, associated with the vertical outlet of pump 16, where the distribution of solids is homogeneous, produces a signal 54, dependent on the solids transport concentration, which is compared in a solid-state differential amplifier 50 with a signal 52 from a second similar densitometer 20 associated with a horizontal section of the pipeline where the spatial concentration would be different due to lagging of the solids near the pipe if the flow velocity were too low. Any difference produces an output 70 which controls a servomotor 80 adjusting the throttle of diesel engine 90 so that sufficient flow velocity is maintained to remove the difference. Solids such as coal, ore, wood, sulphur, potash and liquids such as water and hydrocarbons are referred to.

Optimized diesel engine exhaust silencer

Abstract: An exhaust silencer system for piston type internal combustion engines hag a wet-exhaust, having a muffler and a muffler bypass which contains water at slow and moderate engine speeds, the water being expelled by the exhaust gas pressure at high engine speed, opening said bypass to the flow of exhaust gases thus reducing the exhaust back pressure occurring in the muffler.

Timing signal generator

Abstract: A TIMING SIGNAL GENERATOR FOR PRODUCING ELECTRICAL PULSES TO CONTROL THE ACTUATION OF FUEL-INJECTION VALVES IN A DIESEL ENGINE SYSTEM AND TO PROVIDE AUTOMATIC TIMING ADVANCE A ROTATING APERTURED MASK IS DRIVEN BY THE ENGINE THROUGH A CENTRIGUAL ADVANCE-RETARD DEVICE, AND PHOTOELECTRIC MEANS PRODUCE A TIMING PULSE EACH TIME SAID APERTURED MASK ATTAINS A PREDETERMINED ANGULAR POSITION WITH RESPECT TO THE PHOTOELECTRIC MEANS THE PHOTOELECTRIC MEANS ARE ANGULARLY POSITIONABLE IN RESPONSE TO MOTION OF THE FUEL CONTROL OF THE ENGINE, WHEREBY THE PHOTOELECTRICALLY PRODUCED PULSES HAVE TIME PHASES WHICH VARY NOT ONLY WITH SPEED OF THE ENGINE BUT ALSO WITH THE RATE OF FUEL SUPPLY THERETO, AND PRODUCE CORRESPONDING VARIATIONS IN TIMING ADVANCE

An Experimental and Analytical Investigation of the Gas Exchange Process in a Multi-Cylinder Pressure-Charged Two-Stroke Engine

Abstract: The results are given of a comprehensive investigation of the pressure and temperature diagrams in a multi-cylinder two-stroke engine during the gas-exchange process. A six-cylinder turbocharged two-stroke diesel engine was fully instrumented to record transient pressures in three cylinders, in the scavenge belt, and in a number of positions in a specially designed exhaust pipe. Transient-temperature records were taken in the exhaust pipe. Steady-flow tests were carried out on the inlet ports, the exhaust valves, and the exhaust pipe. The steady-flow data were then used in a computer programme (see references (9) (12)‡) to predict the pressure in the cylinder and the pressures and temperatures in the exhaust pipe.Discounting some measured cylinder-pressure records, which were suspect, the investigation showed good agreement between the predicted and measured pressures in the cylinders and exhaust pipe. The analysis of the temperature records showed there was evidence of mixing and longitudinal heat transf...

Medium Speed Diesel Engine Noise

Abstract: The paper briefly reviews past work on diesel engine noise with particular reference to medium speed engines. A survey carried out on a large number of British and European turbocharged and water-cooled dieseis having bores in the range 2 3/4 in to 33 in (∼ 70 mm to 840 mm) clearly indicated at least two main sources. A qualitative analysis of the problem suggested these to be due to combustion and piston transverse motion in the liner clearance space. None of the engines examined had an International Standards Organization rating lower than Noise Rating 85.A comparison of theoretical trends with those obtained from the survey proved encouraging and application of the analytical findings to five specific engines having bores of 5 in, 8 in, 10 1/4 in, 12 1/2 in and 14 1/4 in (∼ 127 mm, 200 mm, 260 mm, 320 mm and 360 mm) yielded reasonable estimates of the overall noise, but poor approximations to the relevant frequency spectra. Much more work on the effects of crankcase attenuation would appear in order.It...

Improvements in and relating to a method of starting up a reciprocating internal combustion engine and installation for carrying out the method

Abstract: 1, 098, 652. Starting. BURMEISTER & WAIN'S MASKIN-OG SKIBSBYGGERI, A.S. Jan.7, 1966 [Jan.28, 1965], No.932/66. Heading F1K. Apparatus for starting up a reciprocating internal-combustion engine, such as a diesel engine, includes a compressed air source connected through a valve system to the engine, the valve system having a first state wherein air is supplied at a rate sufficient to cause the engine to rotate at its starting speed and a second state wherein air is supplied at a slower rate sufficient only to cause the engine to rotate slowly and includes means for ensuring that the valve system is in its first state when the engine crank-shaft has completed a predetermined rotation from its rest position. As shown the installation comprises a compressed air source 2 connected to the engine 1 through a starting air pipe 3 including a main starting air valve 4, means controlled by a manually operated starting member 12 for opening the valve 4, a by-pass 8 for the main starting air valve 4 and a by-pass valve 9 in the by-pass pipe. The apparatus includes a timing device which is set when the engine stops and which during its period keeps the valve system in its first state and a counting device which receives a pulse for each engine crank-shaft revolution. The counting device may be adapted to change the valve system to its first state only in response to the reception of two pulses. Instead of the electrical control means described it is possible to use hydraulic or pneumatic components or if desired, a combination of such components with electrical components.

Relation between Valve Angle-Area and Low Speed Performance of a Uniflow-Scavenged Engine

Abstract: In order to find the optimum angle-area of the exhaust valve of a two-stroke engine as a function of engine speed, performance tests were carried out with a uniflow-scavenged diesel engine at various speeds under large valve-clearance. The test result showed that the minimum point of indicated specific fuel consumption curve shifted towards lower speed with decreasing valve anglearea, i.e. increasing valve clearance. By analyzing the test results it was theoretically ascertained that the improvement in performance at lower engine speed is mainly due to a decrease in blowdown loss and an increase in charging efficiency. An attempt was then made to control the valve angle-area automatically according to engine speed, by means of a hydraulic tappet with a leak hole, presented in the previous paper. The diameter of the leak hole was chosen so as to give appropriate angle-area for better performance at lower speed on the basis of the above discussion. A performance test with the device showed that fuel consumption improved over the lower speed range, especially under heavy load. The fuel consumption vs. engine speed curve approximately forms an envelope of the ones obtained in preceding tests. However, this tappet has a drawback of high valve seating velocity. This problem must be solved for practical use.

The Introduction of Diesel Power in the United States, 1897–1912

Abstract: The international migration of the diesel engine provides a valuable case study in the interrelationships of entrepreneurship and innovation. As Mr. Lytle demonstrates, however, the introduction of the engine into the United States was far from efficiently managed and the process of technological diffusion was much slower and strained than it might have been.

Paper 5: Compact Long-Life Diesel Engine

Abstract: Continued development work at University College, Dublin, on the variable compression ratio, two-stroke diesel engine, discussed in earlier communications to the Institution, has demonstrated the ability of this unique design to combine long service life with high specific output. The present paper summarizes the current status of the programme after four years' work.The basic design philosophy adopts a two-stroke cycle and exhaust gas turbocharging to obtain high specific output, and an automatic variable compression ratio mechanism to ensure long service life by controlling piston loads.The paper gives details of the variable compression ratio mechanism including the specification of the various components of which it is comprised. Test results show the response rate of the mechanism relative to changes in engine operation. Results are also given for the engine as operated with various air supply blowers to give characteristics suitable for specific user applications.