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Numerical calculations have been carried out to investigate the in-cylinder transient flow structure of a controlled auto-ignition (CAI) engine running at speeds of 1500 rpm and 2000 rpm. The calculated turbulent flow structure and velocities are validated against published laser doppler anemometry (LDA) experimental data (Pitcher et al., 2003). The experimental data was reprocessed to represent the time dependent mean velocities for all measured points. The actual geometry configuration of the engine is imported into the computational fluid dynamics (CFD) code used in this study. The simulations take into account the movement of the inlet, exhaust valves and the piston. The CFD simulations replicate the experimental work where only air was inserted into a driven optical engine. Also, to simulate an engine in controlled auto-ignition (CAI) mode, the same valve timing that allows 36% internal exhaust gas recirculation (IEGR) was applied for the air intake. The calculated results found to agree well with the LDA measurements with an overall agreement of 75.06% at 1500 rpm and 73.42% at 2000 rpm.

Numerical calculations have been carried out to investigate the in-cylinder transient flow structure of a controlled auto-ignition (CAI) engine running at speeds of 1,500rpm and 2,000rpm. The calculated turbulent flow structure and velocities are validated against published laser doppler anemometry (LDA) experimental data. The experimental data were re-processed to represent the time dependent mean velocities for all measured points. The actual geometry configuration of the engine is imported into the computational fluid dynamics (CFD) code used in this study. The simulations take into account the movement of the inlet, exhaust valves and the piston. The CFD simulations replicate the experimental work where only air was inserted into a driven optical engine. Also, to simulate an engine in controlled auto-ignition (CAI) mode, the same valve timing that allows 36% internal exhaust gas recirculation (IEGR) was applied for the air intake. The calculated results are found to agree well with the LDA measurements with an overall agreement of 75.06% at 1,500 rpm and 73.42% at 2,000 rpm.

After validation of the numerical model against published laser doppler anemometry (LDA) experimental data (Pitcher et al., 2003), numerical calculations have been carried out to investigate the in-cylinder transient flow structure of a controlled auto-ignition (CAI) engine running at speeds of 1,500 rpm and 2,000 rpm. The geometry configuration of the engine is imported into the computational fluid dynamics (CFD) code used in this study. The simulations take into account the movement of the inlet, exhaust valves and the piston. To simulate an engine in controlled auto-ignition (CAI) mode, the same valve timing that allows 36% gas residuals was applied to the model. The evolution of the flow pattern inside the cylinder at the symmetrical cross section is described. Also, the turbulence intensity (TI), the turbulent kinetic energy (TKE) and turbulent dissipation rate (TDR) are described for a better understanding of the effect of engine speed on the turbulences generated. The effects of engine speed on fresh charge velocity are also revealed.

THE possibility of adopting the compression ignition engine for use in aircraft is one which has been exciting great interest ever since the War. The advantages claimed for such an engine for any type of aircraft are:—

This paper aims to present experimental experience of heavy fuelling of a spark ignition crankcase scavenged two-stroke cycle unmanned aerial vehicle (UAV) engine, particularly focusing on the effects of compression ratio variation, and to cross-correlate with the results of fluid dynamic modelling of the engine and fuels used.

One-dimensional modelling of the engine has been conducted using WAVE software supported by experimental dynamometer testing of a spark ignition UAV engine to construct a validated computational model using gasoline and kerosene JET A-1 fuels.

The investigation into the effects of compression ratio variation via fluid dynamic simulation and experimental testing has allowed an assessment of the approach for improving heavy fuel operation of UAV engines using auxiliary transfer port fuel injection. The power level achieved with reduced compression ratio heavy fuel operation is equal to 15.35 kW at 6,500 revolutions per minute compared to 16.27 kW from the standard gasoline engine or a reduction of 5.7%.

The studied engine is specifically designed for UAV applications. The validation of the computational models to explore the effects of compression ratio and heavy fuel injection on the solution and cost is supported by experimental tests.

The application of auxiliary port fuel injection of heavy fuel and associated compression ratio optimisation offers an alternative approach to achieve the safety and logistical challenges of the single fuel policy for UAVs. The application of WAVE to simulate crankcase scavenged two-stroke cycle engines has been applied in very few cases. This study shows further exploratory work in that context.

This paper traces the history of Dowty Electronics' involvement in B.I.T.E. over the last ten years; it describes the techniques used, successes and failures, and customer reactions. Applications include the full authority engine control for the Olympus 593 in Concorde, the high integrity wing flaps controller for the BAe 146 shorthaul jet, the engine spool speed limiter for the RB‐211–524 in the Boeing 747, and the high integrity engine bleed valve controller for the RB‐211–535 in the Boeing 757 aircraft.

The formation of azeotropes, ie constant boiling mixtures of two or more components that cannot be separated by fractional distillation, is frequently a problem in solvent recovery. Generally, if the azeotrope is a mixture of solvents containing little or no water, the simplest and most economical solution is to find an outlet for the mixed distillate.

Under this heading are published regularly abstract 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.

FLUSHING (that is cleaning with a copious flow of liquid, usually lubricating oil) is a successful method of clearing circulating systems, such as those of steam turbo‐generators, of impurities; those associated with new installations or those which accumulate in service. This is because as a general rule only relatively light bodied oils are used as lubricants for this type of industrial machinery and again because the contaminants themselves are only loosely bound to the metal surfaces of the system components.

More stringent emission standards are being promulgated all over the world for regulating and decreasing the levels of emission more so caused from on-road vehicles and engines and for improving the air quality problems.

In this study, an attempt has been made to experimentally analyze the performance and emission characteristics of the premixed charge compression ignition (PCCI) mode assisted by a pilot injector.

The results indicate that brake thermal efficiency marginally decreases, and specific fuel consumption increases in all PCCI modes, and HC, CO emissions are higher in the case PCCI modes and oxides of nitrogen and soot levels are considerably reduced in the case of diesel PCCI-biodiesel and petrol PCCI-biodiesel modes.

As obtaining very lean homogenous mixture is hard, it becomes difficult to sustain PCCI mode over the operating range of varying speeds and loads to effectively control the PCCI combustion over the operating range.

Being a responsible human being, we all have the responsibility in keeping this world cleaner, free from all sort of pollution. In this regard, the concept of waste recycling and energy recovery plays a vital role in the development of any economy. This has led to resource conservation and pollution reduction.

The present work Jatropha oil methyl ester (JOME) was chosen as fuels for PCCI mode. Investigations were carried out with blends of JOME with diesel in PCCI combustion mode to evaluate the performance, combustion and emission characteristics of these fuels.