Piston Motion and Thermal Loading Analyses of Two-Stroke and Four-Stroke Cycle Engines for Locomotives

1989 ◽  
Vol 111 (3) ◽  
pp. 536-542 ◽  
Author(s):  
S. D. Haddad

Two-stroke cycle and four-stroke cycle diesel engines are in use in rail traction, with the four-stroke cycle design dominating the field. Cycle simulations using computer programs have shown that the conventional two-stroke cycle is somewhat inferior to its four-stroke cycle counterpart in combustion efficiency and thermal loading. Research at Sulzer concluded that the conventional two-stroke cycle engine is not very suitable for locomotive application. A survey by Ricardos, based on an investigation of engines in current production for traction application, suggested that there are potentials in two-stroke cycle design. This paper presents a summary of the results of a research project concerned with comparison of two well-proven typical locomotive diesel engines, one with a two-stroke cycle and the other with a four-stroke cycle. Performance, mechanical loading, thermal loading, and vibration were chosen as parameters to be investigated to provide information on the status of the two cycles in relation to power range, fuel consumption, reliability, and durability, with a view to assisting the users of locomotive engines to make the correct choice.

2015 ◽  
Author(s):  
Jerry Ng ◽  
Kaisa Honkanen

Emulsified fuel technology has been developed since the early 1980’s to the improve combustion efficiency of marine diesel engines by creating a secondary atomization effect after the initial fuel injection. The main challenge is to measure the improved sfoc of ships accurately and reliably. This paper presents a proposed method to measure the sfoc accurately and reliably to the order of 1%. Electronic governor also poses new challenge to measuring the sfoc of ships burning emulsified fuel. Meanwhile, fuel types supplied to ship owners are of increased varying properties although still complying to ISO8217 standard. This paper describes the innovations in emulsified fuel technology that were developed to meet these challenges.


2020 ◽  
Vol 15 (7) ◽  
pp. 950-957
Author(s):  
G.D. Mezhetskiy ◽  
◽  
V.A. Strelnikov ◽  

The article presents the results of studies of the thermal fatigue strength of diesel cylinder heads and their resource under operating conditions, by using the most advanced technology for their restoration. Based on the results of theoretical calculations of durability and operational studies, a restoration technology has been proposed, which makes it possible to increase the resource of cylinder heads by 2 ÷ 2.5 times. For this purpose, the non-uniformity of the temperature field on the firing bottom of the cylinder heads of YaMZ-238NB diesel engines was theoretically determined and experimentally confirmed. On the basis of theoretical calculations, the most heatstressed sections of the plane of the cylinder heads of diesel engines bonded to the cylinder block were determined, and the appearance of cracks in them. When developing a method for calculating the temperature fields of the fire bottom, the universal finite element method (FEM) was used. This method makes it possible to take into account the geometry and conditions of thermal loading of the cylinder heads quite accurately. For the determination of temperature fields, a well-founded assignment of the boundary conditions is crucial. With this in mind, a number of surfaces were determined that characterize the durability of the entire part during operation. As a result of calculations carried out on a computer, temperature fields have been obtained that make it possible to analyze the distribution of temperatures and temperature gradients at any point of the fire bottom. The highest temperatures (620...635K) are localized in the central part of the fire bottom, which is two times higher in thermal intensity than the peripheral one and confirms the appearance of cracks in these places during the operation of diesel cylinder heads.


Author(s):  
Theodoros C. Zannis ◽  
Dimitrios T. Hountalas ◽  
Elias A. Yfantis ◽  
Roussos G. Papagiannakis ◽  
Yiannis A. Levendis

Increasing the in-cylinder oxygen availability of diesel engines is an effective method to improve combustion efficiency and to reduce particulate emissions. Past work on oxygen-enrichment of the intake air, revealed a large decrease of ignition delay, a remarkable decrease of soot emissions as well as reduction of CO and unburned hydrocarbon (HC) emissions while, brake specific fuel consumption (bsfc) remained unaffected or even improved. Moreover, experiments conducted in the past by authors revealed that oxygen-enrichment of the intake air (from 21% to 25% oxygen mole fraction) under high fuelling rates resulted to an increase of brake power output by 10%. However, a considerable increase of NOx emissions was recorded. This manuscript, presents the results of a theoretical investigation that examines the effect of oxygen enrichment of intake air, up to 30%v/v, on the local combustion characteristics, soot and NO concentrations under the following two in-cylinder mixing conditions: (1) lean in-cylinder average fuel/oxygen equivalence ratio (constant fuelling rate) and (2) constant in-cylinder average fuel/oxygen equivalence ratio (increased fuelling rate). A phenomenological engine simulation model is used to shed light into the influence of the oxygen content of combustion air on the distribution of combustion parameters, soot and nitric oxide inside the fuel jet, in all cases considered. Simulations were made for a naturally aspirated single-cylinder DI diesel engine “Lister LV1” at 2500 rpm and at various engine loads. The outcome of this theoretical investigation was contrasted with published experimental findings.


2018 ◽  
Vol 7 (4.3) ◽  
pp. 47
Author(s):  
Andrii Кravets ◽  
Andrii Yеvtushenko ◽  
Andrii Pogrebnyak ◽  
Yevhenii Romanovych ◽  
Heorhii Afanasov

It was suggested to use group D engine oil with advanced properties instead of group V and G engine oils, which are used in locomotive diesel engines today, to improve the performance of the Ukrainian locomotive fleet of railways.A series of comparative laboratory studies of these oil groups was conducted to substantiate this suggestion which proved better lubrication and tribological performance of group D engine oil and allowed its performance tests.Tests conducted on diesel 5D49 for mileage of more then 100,000 km have demonstrated the advantages of group D oils, such as more stable viscosity, neutralizing ,washing and other properties. Studies on the four-ball wear test machine proved better anti-wear, anti-scoring and anti-friction properties of group D engine oil, which appear even after the continuous use of oils in locomotive diesels. Decrease in burning loss of engine oil was recorded, resulting in the decrease of oil fuel consumption for group D by 30-60% vs. the group G oil.According to the results of performance tests, group D engine oil has been recommended for the use in 5D49 locomotive diesels and some advice on its future implementation have been provided.  


Author(s):  
Michael E. Iden

Abstract The ASME Rail Transportation Division submitted five nominations in 2019 for ASME Historic Mechanical Engineering Landmark status. The nominations are for examples of significant railway technologies involving mechanical engineering and built between 1920 and 1964: 1. SBB 14253 “Crocodile” locomotive (1920): pioneering electric heavy-duty Swiss mountain locomotive, with pioneering features found in many subsequent electric locomotives. 2. Winton 8-201 prototype diesel engine (1933): only surviving of two experimental engines which preceded all GM-Electro-Motive 2-stroke cycle diesel engines for locomotives and other applications; first locomotive diesel engine with lightweight welded steel crankcase and unitized fuel injectors. 3. B&O 50 locomotive (1935): sole surviving example of the first (5) standalone, modular, non-articulated high-speed diesel locomotives from Electro-Motive, functional prototypes for the later “E” passenger and “FT” freight locomotives. 4. Cooper-Bessemer prototype diesel engine (1953): sole surviving example of (4) predecessor 4-stroke cycle diesel engines built for GE Transportation for field test locomotives prior to GE becoming a domestic locomotive manufacturer. 5. SP 9010 locomotive (1964): sole surviving example of (21) experimental German-built diesel locomotives for heavy-duty US mountain railroad operation using a hydromechanical torque converter transmission instead of electric traction motors; proved concept of higher-power and improved wheel-to-rail adhesion. All five nominations were submitted to the ASME national History & Heritage Committee for review. This paper provides a description of each nomination and the status of each proposed railroad Historic Mechanical Engineering Landmark.


Wear ◽  
1984 ◽  
Vol 93 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Yuansheng Jin ◽  
Qiming Yang

Author(s):  
Nigel Bester ◽  
Andy Yates

The performance implications of operating on Synthetic-Paraffinic Kerosene (SPK) were investigated using a RR-Allison T63-A-700 Model 250-C18 B gas turbine and compared to conventional Jet A-1. The SPK was aromatic–free and possessed a greater hydrogen/carbon ratio than petroleum derived Jet A-1. The variation in aromatic content had several implications with respect to soot and NOx emissions. Reduced aromatics also implied a reduction in the radiative heat transfer to the combustor liner. A simple model was used to explore the effect of H/C ratio on the adiabatic flame temperature, the combustor exit temperature and the engine efficiency via the impact on the gas properties and these were compared to the experimental data. It was found that operation with SPK changed directionally toward improving energy extraction via a turbine and an overall efficiency gain of about 1.2% was attained with operation on SPK through increased combustion efficiency, a reduction in liner pressure loss and an improvement in the combustion products properties. A modified combustion liner was fitted to enable the thermal loading on the combustor liner to be investigated and the expected trend with the SPK fuel was confirmed and quantified.


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