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A Theoretical Approach to Assessing the Thermodynamic Process Within the Combustion Chamber of the Propulsive Duct, an Examination of the Potential of the Duct with Special Reference to the Application of Feedback and Spark Discharge Techniques. Development of the propulsive duct has been retarded by the absence of a suitable theoretical analysis. This paper, based on four years of experimental investigation by the author, discusses the problems involved and puts forward a theory which closely follows practical results. The theory is then used to examine the potential of the duct and it is shown that by applying feedback and spark‐discharge techniques, a low specific fuel consumption and unlimited thrust, outside the audible range, is theoretically possible. Finally, it is shown that the marriage of the duct to electrical power generated from atomic sources otters attractive possibilities for V.T.O.L. and aircraft propulsion of the future.

Propulsive thrust generating apparatus having forward propulsive thrust reacting surfaces comprising: a duct; means for introducing into said duct a plurality of fluids which, when mixed, form a combustible mixture; means including a deflector forming a mixing zone in which said fluids are formed into said combustible mixture, said deflector extending along at least a substantial portion of a periphery of said mixing zone and forming a wall of a sheltered combustion zone, and creating turbulence downstream of said sheltered combustion zone; means forming a main combustion zone downstream of said mixing zone; and means effective to establish and maintain an ignition flame in said sheltered combustion zone which ignites said combustible mixture in said main combustion zone and causes continuous flame propagation across said combustible mixture in said main combustion zone with zone with said mixture travelling at a velocity higher than the rate of normal flame propagation in the mixture to cause thrust producing acceleration of said gases reacting against said surfaces.

An approximate graphical method of calculation is presented for evaluation of the flame speed of premixed combustible gases and its relation to the minimum size of burned gas pocket which can propagate a flame. The theory is applied in a semi‐quantitative manner to the problem of the stability limits of a flame anchored to a bluff body in a stream of high velocity gas. Three different approaches to this problem are made, each of which indicates that the velocity of the gas stream at blow‐out should be proportional to the linear dimension of the flame‐holder, the absolute gas pressure, and the square of the laminar flame speed of the combustible gas.

The purpose of this paper is to describe studies of accidental ignition of fuel‐air mixture. Studies were carried out in a laboratory that contains the naturally aspirated aircraft engine LYCOMNIG 320B1A IO type used in the EM‐11C Orka aircraft and the intake system to determine its resilience to the effects of accidental ignition and the occurrence of a backfire.

Tests were performed on a model under extreme conditions (with the intake system closed) and under conditions similar to normal operation using fuels of different combustion rates.

It was found that the positive pressure caused by such accidental ignition under normal operating conditions did not exceed 0.08 bar and did not pose any hazard of damaging the intake system of the IO‐320B1‐type LYCOMNIG naturally aspirated aircraft engine, as designed by the aircraft manufacturer.

The positive results of the tests of the EM11C Orka aircraft intake system's resistance to flashback and other positive test results for this aircraft have contributed to obtaining the EASA.A.115 Certificate and the EASA.21J.117 Certificate for the Design Unit, and the plane was presented at the AERO – Friedrichshafen 2011 Exhibition.

The paper described how, in the laboratory, simulated extreme operating conditions of the naturally aspirated aircraft engine intake system powered aircraft fuels with different burning speeds (aviation gasoline, hydrogen).

The purpose of this paper is to examine the effects of heat capacity and density of biofuels on aircraft engine performance indicated by thrust and fuel consumption.

The influence of heat capacity and density was examined by simulating biofuels in a two-spool high-bypass turbofan engine running at cruise condition using a Cranfield in-house engine performance computer tool (PYTHIA). The effect of heat capacity and density on engine performance was evaluated through a comparison between kerosene and biofuels. Two types of biofuels were considered: Jatropha Bio-synthetic Paraffinic Kerosene (JSPK) and Camelina Bio-synthetic Paraffinic Kerosene (CSPK).

Results show an increase in engine thrust and a reduction in fuel consumption as the percentage of biofuel in the kerosene/biofuel mixture increases. Besides a low heating value, an effect of heat capacity on increasing engine thrust and an effect of density on reducing engine fuel consumption are observed.

The utilisation of biofuel in aircraft engines may result in reducing over-dependency on crude oil.

This paper observes secondary factors (heat capacity and density) that may influence aircraft engine performance which should be taken into consideration when selecting new fuel for new engine designs.

This paper aims to provide graduate students, researchers, governmental and independent agencies with an overview on static electricity.

Static electricity has been studied by researchers, academicians, company specialists, governmental and independent agencies. Static electricity incidents have been collected from several sources such as the technical, general articles, internet web sites, and internal reports. The static electricity definition, incidents, hazards, and static electricity prevention have been reviewed. The static electricity incidents have been arranged and classified into fire, and explosions.

Static electricity can be the cause of problems in many areas of industry. It presents a source of ignition for flammable gases, liquids and powders. It can cause fires and explosions in tankers, aircraft and petrochemical plant and in printing, pharmaceutical, food products and explosives industries.

This paper presents an overview on static electricity, the incidents, and the methods to prevent static electricity generation and accumulation.

EVERYBODY travelling in air or water by its own power applies the reaction or “repulse” principle, that is to say, it either takes up parts of masses contained within itself or, by means of suitable organs, gathers up parts of the surrounding fluid medium and accelerates these masses at a speed greater than its own travelling speed, and this generally in the direction opposite to that in which it desires to travel; whilst in certain cases, in addition to the force produced by the repulse, a further force is obtained through the forward suction of the fluid medium. Devices intended to utilize only the negative pressure produced by suction, e.g. through lateral ejection by means of radial surfaces running at very high (five‐figure) r.p.m. have not, in spite of repeated endeavours, proved successful.

The paper is mainly concerned with how the gas‐turbine designer can choose the best design of liquid or gaseous fuel combustion chamber for his purpose. In the method proposed, combustion chamber test data are expressed in a way which gives the most general information about the design, by introducing dimensionless performance criteria. These criteria are then plotted in ways which enable the various chamber designs to be compared. The treatment deals implicitly with the conditions which satisfactory model tests must fulfil. An idealized model of a gas‐turbine combustion chamber is introduced in the light of which the effects of changes in overall fuel/air ratio can be explained more satisfactorily than when conditions in the flame‐tube are supposed homogeneous.

THE airship Hindenburg was destroyed by fire at 6.25 p.m., E.S.T.,1 May 6, 1937, at the naval air station, Lakehurst, N.J. The airship was completing its first scheduled demonstration flight for the 1937 season, between Frankfurt, Germany, and Lakehurst. It had departed from Frankfurt about 8.15 p.m., G.M.T., Monday, May 3, and was due at Lakehurst on the morning of Thursday, May 6. It was due out of Lakehurst at 10 p.m., E.S.T. that night. Because of unfavourable winds encountered en route, its arrival at Lakehurst was deferred until 6 p.m., Thursday evening, and departure was to be postponed until midnight or later in order to reservice and prepare for the return voyage.

Combustible mixture is heated in a connection e. arranged between a carburetter or a supercharger and the induction manifold, by a stream‐lined pipe g through which hot lubricant passes, a shaft h, which extends therethrough, throwing the lubricant on to the inner walls of the pipe. The lubricant drains into the pipe through a ball bearing on the shaft.