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The purpose of this paper is to find the pressure and the knocking phenomena. To get the pressure values, the butterworth bandpass filter was used and the potential of knocking was found by using peak-to-peak pressure values and also the species concentration. Cooled exhaust gas recirculation was the method used to minimize the knocking occurrence in the engine. Moreover, the effect of premixed methanol and start of engine (SOI) on knocking were also determined.

This paper deals with the compression ignition engine to investigate the unfavorable knocking behavior. The tests were carried out with the 3D model of engine fueled with waste cooking oil blended with TiO2. A number of tests were taken to find the pressure variation and the species concentration at eight different locations in the computational model.

In doing the tests, the positive intended outcome was achieved. From results, it is clear that the SOI and premixed methanol mitigated the knocking process.

The species concentration and pressure in the form of filtered signal were proved to be the ideal methods for evaluating the knocking event in the engine.

RECENT researches by Withrow and Boyd (reference 1) and by Schnauffer (reference 2) each using a different technique, have shown that the phenomenon of knocking is accompanied by an apparently simultaneous reaction of the last part of the charge to burn. Whether the reaction of this part of the charge is actually simultaneous or whether the reaction zone travels with a very high velocity, has not yet been determined. In any case, it will be conceded that the progress of the reaction zone is too rapid to be dependent upon the transfer of heat energy by conduction from the flame front as in normal combustion. In the light of these researches and others, some of which have been carried out in the Aeronautical Engine Laboratory of the Massachusetts Institute of Technology, I believe it is possible to postulate a very simple and reasonable theory of knocking, which fulfils all present requirements and which may in some degree help to remove the veil of mystery which has surrounded the subject.

THERE is probably no one among those listening to me this evening who does not know, or who has not realised through personal experience, the importance of the problem of detonation in internal combustion engine technique. Indeed, since petrol engines have been working on the Beau do Rochas cycle, the phenomenon of “knocking” has been an obstacle—which has gradually been driven into the background, it is true, but which is really insurmountable—to the increase in compression which is recommended by thermodynamics and which experience has shown to produce an increase in output equal to, and even slightly in excess of, the calculated theoretical value.

To describe the development of and experience with a system that tracks the position of knocks and taps atop a large sheet of glass for use as an inexpensive retrofit that can make large windows into interactive interfaces.

The structural‐acoustic wavefront coming from the impact is simultaneously recorded by four contact piezoelectric pickups mounted near the sheet's corners. A digital signal processor extracts relevant characteristics from these signals, such as amplitudes, frequency components, and differential timings, which are used to estimate the location of the hit and derive other parameters, including a degree of confidence in the position accuracy, the strike intensity and the nature of each hit (e.g. knuckle knock, metal tap, or fist bang – our system responds to any kind of impact). A set of heuristically‐guided rules are employed to compare the waveforms recorded by different sensors and determine the differential timing.

Across sensitive areas ranging up to 2×2 m, we have obtained position resolutions of σ=2.5 cm for 1/4 in. tempered glass and σ=3‐4 cm for 1 cm thick shatterproof glass. Our system delivers 65 ms latency, hence is essentially real time. The system has been installed in several public settings, and has proven to be very robust.

Suggestions are given for doing everything in software and not using the DSP. Analytical compensation of the dispersion would probably yield better precision but require more computation time.

As this system requires only simple hardware, it needs no special adaptation of the glass pane, and allows all tracking transducers to be mounted on the inner surface, hence it is quite easy and inexpensive to deploy as a retrofit to existing windows. This opens many applications, such as an interactive storefront, with content controlled by knocks on the display window, an interactive museum display case, or a vending machine where one can select by tapping directly above the desired item.

As large displays become less costly and more common, systems like these can make them interactive. This paper details our approach.

THE Deutsche Versuchsanstalt für Luft‐fahrt—known for short as the D.V.L.—at Berlin‐Adlershof, is the central establishment for aeronautical research in Germany. Hitherto the D.V.L. had as its special prerogative the testing of aircraft and aero‐engines for certificates of airworthiness. Since April 1, 1933, the Inspection Department has passed under the authority of the “Reichsamt für Flugsicherung” (Air Security Board), but it has not actually been separated from the D.V.L., continuing to have its premises at the D.V.L. establishment. (Further details of the Inspection Department are given later.)

An account of tests carried out at Chalais Meudon for the purpose of investigating the detonating properties of fuels by means of a new calorimetric method which only requires measurements of the heat acquired by the cooling water in the cylinder jackets. The plant used includes a single‐cylinder laboratory engine designed by the Ethyl Gasoline Corporation for investigations of knocking by the Midgley method, but adapted at Chalais for measurements of temperature, and a 250‐h.p. six‐cylinder engine to normal aero‐engine design with special apparatus for the delivery and collection of the cooling water enabling accurate gauging of quantities and heat In addition, tests have also been carried out with a 450‐h p. aero‐engine, the special advantage of the calorimetric method being that investigations of fuels can be effected directly on the engine in which the fuel is to be used. The fuels investigated in the tests reported on were mixtures of petrol with benzol in quantities varying from 10 per cent to 40 per cent, or petrol with small admixtures of fluid ethyl (tetra‐ethyl of lead) or iron carbonyl. It was found that the addition of 40 per cent benzol or of 0·775 per cent ethyl fluid had the same effect as regards elimination of knocking.

The purpose of this paper is to investigate the knock combustion characteristics, including the combustion pressure, heat release rate (HRR) and knock intensity of aviation kerosene fuel, that is, Rocket Propellant 3 (RP-3), on a port-injected two-stoke spark ignition (SI) engine.

Experimental investigation using a bench test and the statistical analysis of data to reflect the knock combustion characteristics of the two-stroke SI unmanned aerial vehicle (UAV) engine on RP-3 kerosene fuel.

Under the full load condition of 4,000 rpm, at the ignition timing of 25 degree of crank angle (°CA) before top dead centre (BTDC), the knock combustion is sensitive to the thinner mixture; therefore, the knock begins to occur when the excess air ratio is larger than 1.0. When the excess air ratio is set as 1.2, the knock obviously appears with the highest knock intensity. At the excess air ratio of 1.2, better engine performance is obtained at the ignition timing range of 20-30 °CA BTDC. However, the ignition timing at 30° CA BTDC significantly increases the peak combustion pressure and knock intensity with the advancing heat release process.

Gasoline has a low flash point, a high-saturated vapour pressure and relatively high volatility, and it is a potential hazard near a naked flame at room temperature, which can create significant security risks for its storage, transport and use. The authors adopt a low-volatility single RP-3 kerosene fuel for all vehicles and equipment to minimise the number of different devices using various fuels and improve the military application safety.

Most two-stroke SI UAV engines for military applications burn gasoline. A kerosene-based fuel for stable engine operation can be achieved because the knock combustion can be effectively suppressed through the combined adjustment of the fuel amount and spark timing.

January 15, 1973 Ironfoundry — Statutory duty — Breach — Noxious dust — Prolonged inhalation of noxious dust — Chronic lung illness — Employers' actual or constructive knowledge of health hazard — Test to apply when determining constructive knowledge — Whether employer should be aware of recent medical or scientific knowledge — Factories Act, 1961 (9 & 10 Eliz.II, c.34), ss.4(l), 63(1).

Analyses the role of change and innovation and goes on to discuss the innovation process and ten sources of innovation for the first stage – the search. These are: unexpected successes, failures, external events, process weaknesses, industry/structure changes, high‐growth areas, converging technologies, demographic and perception changes and new knowledge.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics and publications of other similar research bodies as issued