Piston Temperatures in a Sleeve Valve Oil Engine

The paper describes tests on a Mirrlees-Ricardo sleeve valve engine of inches bore, running at speeds up to 1,400 r.p.m. The pistons used were: (1) a simple piston of cast iron; (2) a piston with tapered head section, cast in “L8” alloy; and (3) a heavily ribbed and strutted piston of “Y” alloy. A robust form of thermocouple gear which has been devised is described in the paper, and the probable errors are discussed. The temperatures attained by a number of points in each piston are shown for various conditions. The effect of the sleeve is much less than might be expected. The rates of heat reception by the central and outer portions of the piston head differ considerably owing to the vortex type of combustion chamber used. Values of these rates have been estimated for different loads and speeds. The alloy pistons become warm in about half the time required by the cast iron piston. Piston temperature appears to be a linear function of engine speed, the alloy pistons showing an increase of 42 deg. C. at the centre when the speed was increased from 800 to 1,400 r.p.m. at constant brake mean effective pressure. The temperatures of the lower edges of ribs of moderate depth were only 10–18 deg. C. cooler than the under surface of an unribbed piston. Distortion of the pin seatings due to the expansion of the struts must be very slight. With normal water circulation and a constant temperature of water supply, piston temperatures in this engine are almost independent of the final temperature of the water.

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EFFECT OF LOWER ETHANOL GASOLINE BLENDS ON PERFORMANCE AND EMISSION CHARACTERISTICS OF THE SINGLE CYLINDER SI ENGINE

International Journal of Instrumentation Control and Automation ◽

10.47893/ijica.2012.1049 ◽

2012 ◽

pp. 266-269

Author(s):

V. S. KUMBHAR ◽

D. G. MALI ◽

P. H. PANDHARE ◽

R. M. MANE

Keyword(s):

Fuel Consumption ◽

Engine Speed ◽

Automotive Application ◽

Emission Characteristics ◽

Effective Pressure ◽

Si Engine ◽

Single Cylinder ◽

Performance And Emission ◽

Brake Mean Effective Pressure ◽

Co Emission

Alcohols, basically ethanol is considered as a leading alternative fuel for automotive application because of its ability to reduce the air pollution and cost of the fuel. This paper investigates the effect of lower ethanol gasoline blends (up to 20% by volume) on performance and emission characteristics of the single cylinder four stroke SI engine. Tests were carried out for power, torque, fuel consumption and brake mean effective pressure, while exhaust emissions were analyzed for CO, CO2, and HC by using different ethanol gasoline blends on volume basis at wide open throttle and variable engine speed from 4000 to 8000 rpm. Results were compared with the pure gasoline. It showed that as the ethanol content increases the power, torque, fuel consumption, brake mean effective pressure and CO2 emission while reduces HC and CO emission.

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Computer Modelling For 4-Stroke Direct Injection Diesel Engine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.33-37.801 ◽

2008 ◽

Vol 33-37 ◽

pp. 801-806

Author(s):

Abdul Rahim Ismail ◽

Rosli Abu Bakar ◽

Semin Ali ◽

Ismail Ali

Keyword(s):

Diesel Engine ◽

Simulation Study ◽

Engine Speed ◽

Computer Modelling ◽

Direct Injection ◽

One Dimension ◽

Effective Pressure ◽

Operational Parameters ◽

Direct Injection Diesel Engine ◽

Theoretical Results

Study on computational modeling of 4-stroke single cylinder direct injection diesel engine is presented. The engine with known specification is being modeled using one dimension CFD GT-Power software. The operational parameters of the engine such as power, torque, specific fuel consumption and mean effective pressure which are dependent to engine speed are being discussed. The results from the simulation study are compared with the theoretical results to get the true trend of the results.

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Matching and Optimisation of Turbochargers for Upgradation of High Horse Power Diesel Electric Locomotives for Indian Railways

ASME 2005 Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/ices2005-1103 ◽

2005 ◽

Cited By ~ 2

Author(s):

Anirudh Gautam ◽

Avinash Kumar Agarwal

Keyword(s):

Engine Speed ◽

Thermal Loading ◽

Fuel Efficiency ◽

Operating Point ◽

Inlet Temperature ◽

Test Bed ◽

Optimum Configuration ◽

Air Inlet ◽

First Case ◽

Brake Mean Effective Pressure

As a part of the upgradation program of its fleet of 1940 kW diesel electric locomotives, Indian Railways undertook evaluation, matching and optimization of different turbochargers. The objective was to increase engine output, improve fuel efficiency and limit thermal loading. Trials with different makes of turbochargers using different combinations of diffuser, nozzle rings and compressors were carried out for identifying the optimum configuration for an uprated engine rating of 2310 kW. Test bed evaluations have been carried out on Research Design & Standards Organization (RDSO) test beds for four different designs of turbochargers with different configurations. Two types of surge tests were carried out at each operating point i.e. constant brake mean effective pressure (BMEP) and constant power. In the first case, BMEP was kept constant and engine speed varied and in the second case, power was kept constant and engine speed was varied. The tests consisted of recording the parameters at various combinations of engine speed and power. With different combinations, the highest operating point for a test was governed by peak firing pressures. Some of the parameters, which were monitored, were the compressor air inlet temperature, representative peak firing pressures, turbine inlet temperature, average cylinder head temperature, brake specific fuel consumption (BSFC) and air manifold temperature. This paper discusses the methods adopted in carrying out these evaluations and optimizations and the results obtained thereof along with the decision criteria for making final selections.

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Comparison of Physics-Based, Semi-empirical and Neural Network-based Models for Model-based Combustion Control in a 3.0 L Diesel Engine

Energies ◽

10.3390/en12183423 ◽

2019 ◽

Vol 12 (18) ◽

pp. 3423 ◽

Cited By ~ 1

Author(s):

Hu ◽

d’Ambrosio ◽

Finesso ◽

Manelli ◽

Marzano ◽

...

Keyword(s):

Neural Network ◽

Steady State ◽

Diesel Engine ◽

Effective Pressure ◽

Combustion Control ◽

Ann Model ◽

Control Applications ◽

Model Based ◽

Brake Mean Effective Pressure ◽

Semi Empirical

A comparison of four different control-oriented models has been carried out in this paper for the simulation of the main combustion metrics in diesel engines, i.e., combustion phasing, peak firing pressure, and brake mean effective pressure. The aim of the investigation has been to understand the potential of each approach in view of their implementation in the engine control unit (ECU) for onboard combustion control applications. The four developed control-oriented models, namely the baseline physics-based model, the artificial neural network (ANN) physics-based model, the semi-empirical model, and direct ANN model, have been assessed and compared under steady-state conditions and over the Worldwide Harmonized Heavy-duty Transient Cycle (WHTC) for a Euro VI FPT F1C 3.0 L diesel engine. Moreover, a new procedure has been introduced for the selection of the input parameters. The direct ANN model has shown the best accuracy in the estimation of the combustion metrics under both steady-state/transient operating conditions, since the root mean square errors are of the order of 0.25/1.1 deg, 0.85/9.6 bar, and 0.071/0.7 bar for combustion phasing, peak firing pressure, and brake mean effective pressure, respectively. Moreover, it requires the least computational time, that is, less than 50 s when the model is run on a rapid prototyping device. Therefore, it can be considered the best candidate for model-based combustion control applications.

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Effects of the oil and liquid fuel film on hydrocarbon emissions in spark ignition engines

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/09544070260340853 ◽

2002 ◽

Vol 216 (9) ◽

pp. 759-771 ◽

Cited By ~ 7

Author(s):

S Yu ◽

K Min

Keyword(s):

Liquid Fuel ◽

Engine Speed ◽

Spark Ignition Engines ◽

Fuel Film ◽

Warm Up ◽

Oil Film ◽

Piston Head ◽

Hc Emissions ◽

Piston Crevice ◽

Desorption Mechanism

A model was developed to assess the absorption and desorption of fuel in oil film and in the binary diffusion of oil and fuel films. This was investigated with a parametric study according to engine speed, load and oil film temperature. The results show that Henry's constant, which is related to solubility, is the most dominant parameter in the absorption/desorption mechanism of fuel into the oil film. Under warm-up conditions, engine speed had little influence on the amount of fuel absorbed/desorbed, but when the oil film temperature was low, the quantity of fuel absorbed/desorbed decreased with increasing engine speed. Liquid fuel on the oil film and piston head caused higher hydrocarbon (HC) emissions, and under base conditions (a simulated cold engine), the amount of fuel vaporized from fuel film and desorbed from wetted oil film was 24.5 per cent of the stoichiometric fuel mass. The effect of oil film with liquid fuel was 5.3 times larger than that of oil film without liquid fuel. The amount of fuel that escaped from the piston crevice was 1.3 times larger than that of fuel in the oil film. However, the fuel trapped in the oil film desorbed into the combustion chamber more slowly than the fuel that escaped from the piston crevices under cold engine conditions.

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Throttleless Premixed-Charge Engines: Concept and Experiment

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/pime_proc_1994_208_153_02 ◽

1994 ◽

Vol 208 (1) ◽

pp. 13-24 ◽

Cited By ~ 3

Author(s):

P D Ronney ◽

M Shoda ◽

S T Waida ◽

E J Durbin

Keyword(s):

Carbon Monoxide ◽

Thermal Efficiency ◽

Equivalence Ratio ◽

Practical Implementation ◽

Effective Pressure ◽

Unburned Hydrocarbon ◽

Brake Mean Effective Pressure ◽

Lean Misfire Limit

A method of controlling the brake mean effective pressure (b.m.e.p.) of a premixed-charge engine is proposed which does not require the use of a throttle and does not exhibit significant throttling losses. In this method, a combination of adjustment of the mixture equivalence ratio and preheating of the mixture is used to control the b.m.e.p. The preheating serves two purposes: it reduces the density of the mixture and it broadens the lean misfire limit. Experiments on the performance of engines controlled with this strategy are compared with conventional throttled engines. As much as 16 per cent improvement in thermal efficiency was observed at the same b.m.e.p. The untreated NOx emissions are found to be much lower in the throttleless engine at the same b.m.e.p. while carbon monoxide (CO) and unburned hydrocarbon (UHC) emissions are comparable to but somewhat higher than throttled engines. Practical implementation of the concept is discussed.

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Effects of EGR and Boost Pressure on Reactivity Controlled Compression Ignition (RCCI) Engine at High Load Operating Conditions

Volume 1: Large Bore Engines; Fuels; Advanced Combustion; Emissions Control Systems ◽

10.1115/icef2014-5485 ◽

2014 ◽

Cited By ~ 3

Author(s):

Yifeng Wu ◽

Rolf D. Reitz

Keyword(s):

Peak Pressure ◽

Pressure Rise ◽

High Load ◽

Operating Conditions ◽

Boost Pressure ◽

Compression Ignition ◽

Effective Pressure ◽

Reactivity Controlled Compression Ignition ◽

Brake Mean Effective Pressure ◽

Diesel Injection

Reactivity Controlled Compression Ignition (RCCI) at engine high load operating conditions is investigated in this study. The effects of EGR and boost pressure on RCCI combustion were studied by using a multi-dimensional computational fluid dynamics (CFD) code. The model was first compared with a previous CFD model, which has been validated against steady-state experimental data of gasoline-diesel RCCI in a multi-cylinder light duty engine. An RCCI piston with a compression ratio of 15:1 was then proposed to improve the combustion and emissions at high load. The simulation results showed that 18 bar indicated mean effective pressure (IMEP) could be achieved with gasoline-diesel RCCI at an EGR rate of 35 % and equivalence ratio of 0.96, while the peak pressure rise rate (PPRR) and engine combustion efficiency could both be controlled at reasonable levels. Simulations using both early and late direct-injection (DI) of diesel fuel showed that RCCI combustion at high load is very sensitive to variations of the exhaust gas recirculation (EGR) amount. Higher IMEP is obtained by using early diesel injection, and it is less sensitive to EGR variation compared to late diesel injection. Reduced unburned hydrocarbon (HC), carbon monoxide (CO), soot and slightly more nitrogen oxides (NOx) emissions were seen for early diesel injection. HC, CO and soot emissions were found to be more sensitive to EGR variation at late diesel injection timings. However, there was little difference in terms of peak pressure, efficiencies, PPRR and phasing under varying EGR rates. The effect of boost pressure on RCCI at high load operating conditions was also studied at different EGR rates. It was found that combustion and emissions were improved, and the sensitivity of the combustion and emission to EGR was reduced with higher boost pressures. In addition, cases with similar combustion phasing and reasonable PPRR were analyzed by using an experimentally validated GT-Power model. The results indicated that although higher IMEP was generated at higher boost pressures, the brake mean effective pressure (BMEP) was similar compared to that obtained with lower boost pressures due to higher pumping losses.

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Performance Investigation of an Eight Cylinder Gasoline Engine

Volume 12: Transportation Systems ◽

10.1115/imece2014-40417 ◽

2014 ◽

Author(s):

Ali Kilicarslan ◽

Mohamad S. Qatu

Keyword(s):

Experimental Work ◽

Engine Speed ◽

Gasoline Engine ◽

Mechanical Efficiency ◽

Effective Pressure ◽

Air Mass ◽

Engine Torque ◽

Gasoline Engines ◽

Temperature And Pressure ◽

Engine Power

Performance investigation of a Chevrolet 5.7, eight cylinder gasoline engine is experimentally carried out at laboratuary conditions by means of the special softwares called “NetDyn” and “WinDyn”. This experimental work is intended to make contribution to the researchers that experimentally analyze the parameters of gasoline engines with the engine speed in detail. During the experiments, the engine speed is changed from 2500 rpm to 5250 rpm with 250 rpm intervals and steptime for succesive speeds is kept constant as 10 s. Engine power, engine torque, fuel and air flowrates per kW, mechanical efficiency, oil temperature and pressure, break mean effective pressure and exhaust temperatures are measured as a function of engine speed. As the engine speed was increased, it was observed that the air mass flow rate, exhaust and oil temperatures increased while the break mean effective pressure, mechanical volumetric efficiency, and engine torque decreased. Engine power increased between the engine speeds of 2500 rpm and 3750, but it decreased between the speeds of 3750 rpm 5246 rpm.

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