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Viewing 1 to 17 of 17
2017-03-28
Technical Paper
2017-01-1606
Sergey P. Gladyshev, Pavel Gladyshev, Irina Okrainskaya
Abstract In this paper, we consider a new design of synchronous motor with salient poles rotor and all coils placed on the stator. This design, uses a laminated silicon steel rotor, which is not so expensive as a rotor with super strong permanent magnets. This design of machine eliminates copper rings on the rotor and brushes which is used in regular synchronous motors, and eliminates disadvantages involved with these arrangements. In an earlier publication, authors considered the opportunity realization of synchronous mode operation in the machine with salient pole rotor and DC stator excitation. Now, we consider the new synchronous mode operation with individual DC excitation of each the alternative current (AC) windings for realization the first, second and third phase synchronous machines. In theoretical basics of analyses and design of synchronous motors we pay more attention to the single-phase motor because it is the basis for design polyphase synchronous machines.
2016-04-05
Technical Paper
2016-01-0001
Sergey P. Gladyshev, Pavel Gladyshev, Irina Okrainskaya
Abstract DC motors are the most controllable electrical machines but more complicated for fabrication, in comparison with induction motors having simplified design but more complicated for control. Regular DC motor contain excitation (field) coil on the stator and armature coil on the rotor. Armature coil connected with external voltage source by a mechanical commutator with brushes. This arrangement complicates fabrication of DC machine, increases its cost, lowered reliability, and demands regular maintenance. Electromagnets inside of the stator increase dimensions of DC motor. In DC motor with salient pole rotor, there are no coils on the rotor, and mechanical commutator with brushes is eliminated, and eliminated all disadvantages connected with this arrangement. In this paper, we consider the new version of DC machine with DC stator excitation in compare with presented earlier. The difference is in using individual coil excitation for each armature coil, placed on the stator.
2015-04-14
Technical Paper
2015-01-0151
Sergey P. Gladyshev, Irina Okrainskaya, Pavel Gladyshev
Abstract The purpose of this paper is to investigate opportunity to create a new type AC induction motor with the salient pole rotor (without winding) and both winding AC excitation and short circuited placed on the stator. There are some advantages in this design: The suggested design has a cold rotor. The stator short circuited and excitation windings are easier for cooling. The rotor has reduced weight in compare with regular induction motor rotor. The short circuit winding can be used for the current control like in the regular induction wound-rotor machines. In this case, the problem maintenance of the slip rings is eliminated. In this paper, we discuss theoretical opportunity for realization the induction mode operation in two and three phase machines. As a base for this, it serves the analyses operation of one phase machine. This analysis is fulfilled in comparison with regular induction motors with short circuited and wound-rotor windings.
2012-09-10
Technical Paper
2012-01-1711
Ian Whelan, William Smith, David Timoney, Stephen Samuel
This work investigates the effect of engine operating conditions and exhaust sampling conditions (i.e. dilution ratio) on engine-out, nano-scale, particulate matter emissions from a gasoline direct-injection engine during cold-start and warm-up transients. The engine used for this research was an in-line four cylinder, four stroke, wall-guided direct-injection, turbo-charged and inter-cooled 1.6 l gasoline engine. A fast-response particulate spectrometer for exhaust nano-particle measurement up to 1000 nm was utilized, along with a spark-plug mounted pressure transducer for combustion analysis. It was observed that the total particle count decreases during the cold-start transient, and has a distinct relationship with the engine body temperature. Tests have shown that the engine body temperature may be used as a control strategy for engine-out particulate emissions.
2009-11-02
Technical Paper
2009-01-2791
Edward J. Casey, William J. Smith, David J. Timoney
With increased numbers of vehicles on Irish roads, there is now a need to be able to scientifically assess the quantity of pollutant material to which populations are exposed. Traditionally, emissions have been determined using kinematic (vehicle speed) data but recent studies have identified that other parameters are of interest. The work in this Paper focuses on the development and testing of a purpose-built software system to extract on-board diagnostic data from a vehicle in order to derive a driving cycle and to use other engine characteristic data to better inform local pollutant and energy consumption models for Dublin. Comparisons with GPS data shows the system to be cost effective (price and computing overhead) and reliable.
2004-03-08
Technical Paper
2004-01-1066
Colm O'Kane, Sean Timoney
An algorithm was developed for a speed-dependent four-wheel steering system for a Formula SAE car. A linear bicycle model was implemented using the MATLAB and SIMULINK software packages. Various control laws were investigated for the rear steer angle with the objective of reducing the sideslip angle. A full 3D model of the vehicle incorporating weight transfer and tire non-linearity was then developed using the DADS software. An algorithm developed using the linear model with the aim of reducing vehicle sideslip angle was implemented in the nonlinear model. It is shown that this algorithm can improve the dynamic performance for both high-speed and low-speed maneuvers.
1997-10-01
Technical Paper
972970
William J. Smith, David J. Timoney, Dermot P. Lynch
This paper presents experimental results obtained from bench tests on a 1.4 litre, 4-cylinder, dual-fuel spark ignition engine, fitted with a three-way catalytic converter. Performance, fuel consumption and exhaust emissions measurements were recorded under steady state operating conditions from engine builds: (i) with multi-point gasoline liquid fuel injection, and (ii) with single-point vaporised LPG (propane). An after-market LPG conversion kit, incorporating electronic air-fuel ratio control based on exhaust oxygen concentration, was used in the latter case. Emissions were measured before and after the catalytic converter and catalyst conversion efficiency trends are presented for each fuel. The experimental data is also compared with predictions from a thermodynamic cycle simulation and emissions prediction model which was developed with a view to gaining an improved understanding of the observed experimental trends.
1997-02-24
Technical Paper
970831
Aidan M. Ryan, David J. Timoney
Tests have been carried out over a wide range of operating conditions on a single circuit plate-finned tube type of refrigerant evaporator, exchanging heat between ambient air and refrigerant R134a. Uniform and non-uniform air flow distributions were applied with the objective of studying the effects of non-uniformity on heat transfer. The experimental results revealed that, for a given total volume flow of air, heat transfer performances could be up to 15% better with a non-uniform flow where turbulence levels were also high. Extensive comparisons were also made between these measurements and predictions from a computer model. This was designed to simulate the thermal behavior of cross-flow heat exchangers on a tube segment-by-segment basis, allowing for flow non-uniformity. Predictions were found to match measurements satisfactorily for test cases involving uniform air flows and a relatively large temperature difference between fluids.
1997-02-24
Technical Paper
970336
Damien Clarke, William J. Smith
This paper describes the application of a variable-phase I.C.R.V. to a modern 4-valve automotive engine with electronic fuel injection and lambda feedback control. Some of the difficulties associated with applying an I.C.R.V. to this kind of engine are discussed. Performance and emissions data are presented for both the baseline (throttled) and I.C.R.V. configurations, and the data compared with predictions from a computer simulation.
1997-02-24
Technical Paper
971013
Dermot Lynch, William J. Smith
The various methods for calculating AFR from exhaust gas analysis do not always produce identical results. This paper presents exhaust gas analysis data from a four-stroke SI engine burning two different fuels - unleaded gasoline and LPG. Exhaust gas concentrations are measured both upstream and downstream of the three-way catalyst. All four sets of data are analysed using established algorithms due to Spindt, Urban, Uyehara and Fukui. The results of each algorithm are compared with the AFR obtained using direct measurement of air and fuel mass flows.
1997-02-24
Technical Paper
970900
David J. Timoney, Barry Brophy, William J. Smith
This paper describes the results of an experimental programme designed to investigate some effects of intake flow-generated turbulence on rates of combustion and emissions formation in a 91mm bore direct injection diesel engine. Swirl and squish were eliminated as far as possible, in order to isolate the desired effects. This was achieved by re-modelling the inlet port and by replacing the deep bowl piston cavity with a flat-topped version, with the same compression ratio. Tests were carried out with three inlet valves: a standard engine Valve (“A”) and two drilled shrouded valves, one with 15 x 6 mm dia. holes (“B”) and one with 40 x 3.5 mm dia. holes (“C”). The turbulence characteristics associated with each valve were first determined on a steady flow rig, using LDA based surveys of velocity distributions at different downstream distances. The objective was to measure absolute levels of turbulence intensity and to study the subsequent rate of decay.
1996-02-01
Technical Paper
960035
David J. Timoney, William J. Smith
Heat release and instantaneous injection rate data was obtained from a series of experiments on a 121mm bore, single-cylinder, deep-bowl, non-swirling D.I. diesel research engine, using a variety of fuel injection pump builds. Results from tests at constant air-fuel ratio and constant start of combustion angle show that increasing the mean fuel injection kinetic energy (M.I.K.E.) at a given engine speed reduces the heat release time and increases the fuel-air mixing rate. Also, at constant fuel injection kinetic energy, increasing the engine speed increases the fuel-air mixing rate. These experimental trends have been interpreted with the aid of a novel but mathematically very simple analytical approach, based on the hypothesis that all fuel-air mixing in a DI diesel combustion system is promoted by kinetic energy inputs. A “Combined Mixing Efficiency” has been identified which appears to be a characteristic constant of a DI diesel combustion system geometric configuration.
1995-02-01
Technical Paper
950214
David J. Timoney, William J. Smith
This paper presents data obtained from a single-cylinder direct injection diesel research engine (121mm bore × 139mm stroke) fitted with a deep torroidal piston cavity but which was fitted with a detachable-port cylinder head and could be operated both with and without swirl. Tests were carried out with a number of different fuel injection pump plunger sizes (which yielded significant changes in injection rate patterns) and the results have been analysed with the aid of a computer program (INJECT) which can be used to determine instantaneous rates of fuel injection, based on data acquired from a firing engine. The results indicate that observed changes in emissions levels can be explained in terms of variations in the instantaneous injection rates. In particular, for a given engine speed, a strong correlation has been shown to exist between NOx emissions and the volume of fuel injected during the ignition delay period, particularly at high engine loads.
1992-10-01
Technical Paper
922224
William J. Smith, David J. Timoney
This paper presents a new approach to the problem of determining instantaneous rates of fuel injection in direct injection diesel engines. A computer-based analysis tool has been developed which uses experimental data for fuel line pressure (measured at any point downstream of the fuel pump), needle lift and cylinder pressure as inputs to a fluid flow calculation routine. This uses a “method of characteristics” solution to the equations governing unsteady, one-dimensional flow of a compressible liquid in the fuel line and within the injector body. The technique can be used to determine instantaneous injection rates on a cycle-by-cycle basis in a running engine.
1985-02-01
Technical Paper
850462
Sean S. Timoney
This paper describes a computer program for optimising the bending and contact strength of the spur gears in a planetary hub reduction set. Classical optimisation techniques are not employed because of the complexity of the problem and the number and variety of constraints encountered. Instead, the approach described covers the complete design space and successively filters out solutions that do not meet the required constraints. Thus the very large design space is reduced to a relatively few possible solutions whose properties can then be examined by the designer, leaving the final trade-offs to his discretion.
1985-02-01
Technical Paper
850568
Eanna Timoney, Sean Timoney, Seamus Timoney
Airport crash rescue vehicles are required to match limit conditions of performance in regard to acceleration, mobility and load carrying capability, with a very high degree of “on-the-day” reliability to meet emergency conditions. This paper describes a unique range of vehicles, which comprises four, six, and eight wheel drive vehicles, with independent suspension and an all up weight from 12 to 28 tonnes. Installed power is from 340 to 550 horse power (255 to 413 kW) and all vehicles drive through an automatic change speed gear box to a transfer box and thence to rigidly mounted axles with controlled slip differentials. Ventilated disc brakes with servo actuation are used on all wheels and crew cabs are designed for optimum crew safety.
1983-02-01
Technical Paper
830313
S. Timoney, G. Flynn
Structural ceramic components have been successfully operated in a diesel engine. The pistons, liner, and housing for an opposed piston, two-cycle (valveless) engine were fabricated from sintered alpha SiC. The ceramic engine was tested without any lubrication or cooling in the cylinder. Data was collected for both the motoring and firing tests for discussion.
Viewing 1 to 17 of 17

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