Influence of cavitation on the working surfaces of the cylinder&piston group of a diesel engine during maintenance

2021 ◽  
pp. 30-34
Author(s):  

It is established, that the destruction of carbon deposits when the engine is running on a water-fuel emulsion occurs due to the phenomenon of micro-impact of emulsified fuel droplets, the evaporation rate of which depends on their diameter, pressure and amplitude of the gaseous medium. As a result of the removal of carbon deposits in the engines, there is an increase in the average compression value for the engine cylinders by 8 % and the engine power by 11 %, as well as a decrease in the specific fuel consumption by 10 % and the smoke of the exhaust gases by 16 %. Keywords: engine, water-fuel emulsion, micro-impact, emulsified fuel, compression. [email protected]

2019 ◽  
pp. 28-37
Author(s):  
Andriy Marchenko ◽  
Volodymyr Shpakovskyy ◽  
Volodymyr Volikov

Taking into account the oil resources depletion the requirements to fuel consumption of internal combustion engines are now increasing as well as to their reliability and durability. With the continual increase in the number of internal combustion engines in operation, along with the problem of parts of the cylinder piston group wearing out has caused exhaust from such engines to be one of the main source of harmful pollutant emissions in cities. Therefore, environmental requirements have in turn increased dramatically. The engine resource and its efficiency largely depend on the process of fuel combustion in the combustion chamber. Experimental studies aimed to improve the working process on diesel engines by piston insulation have shown an effective decrease in fuel consumption by reducing heat loss and more complete fuel combustion. When oxide ceramic coatings were used on the piston and cylinder head, the maximum power increased and the specific fuel consumption decreased. However ceramic coatings are not widely used due to their peeling. We have developed a technology for the galvanic plasma treatment of pistons, which made it possible to obtain on the pistons surface made of aluminum alloys a ceramic corundum layer with high adhesion to the base metal that does not peel and has electret properties. In 1993, pistons with a corundum surface layer were installed in a shunting diesel locomotive and life-time running tests were conducted. Such pistons increased wear resistance, reduced the wear of cylinder liners, increased the strength of the annular jumpers, and were not prone to burnouts and scuffing. They provided an increase in the resource of the cylinder-piston group of the diesel engine by more than 125 thousand engine hours. The paper provides an analysis of the effect of corundum pistons thermal insulation on significant increasing the, engine power and fuel consumption reduction. Basing on experimental bench studies of a gasoline engine, a tractor diesel engine and long-term operational life tests of diesel engines, an attempt had been made to explain the reasons for the improvement in the engines’ efficiency.


Author(s):  
A.V. Golenishev ◽  
A.V. Nadezkin ◽  
M.E. Starchenko

Рассматриваются подходы по определению пороговых значений концентрации продуктов износа в отработанном цилиндровом масле, характеризующие переход объекта диагностирования судового крейцкопфного дизеля из одного технического состояния в другое. Показано, что существующие методики не учитывают индивидуальные особенности и техническое состояние деталей цилиндропоршневой группы. Предложено для решения задачи их трибодиагностики использовать разработанную имитационную модель, позволяющую провести моделирование процесса изнашивания цилиндровой втулки и поршневых колец судового дизеля и на основании полученных расчетов определить концентрацию продуктов износа поступивших в отработанное цилиндровое масло при различной скорости изнашивания трущихся деталей. Данные о фактической концентрации продуктов износа в отработанном цилиндровом масле в дальнейшем соотносятся с результатами моделирования, что позволяет оценить техническое состояние деталей цилиндропоршневой группы двигателя. Представлены результаты моделирования по определению пороговых значений концентрации продуктов износа в отработанном цилиндровом масле, характеризующее переход судового дизеля из исправного в несправное техническое состояние. Даны практические рекомендации по выбору пороговых значений содержания продуктов износа в отработанном цилиндровом масле для различных типов судовых крейцкопфных дизелей и условий их эксплуатации.The article examines approaches to determine the threshold values of the concentration of wear debris in used cylinder oil that characterize the transition of a ship crosshead diesel engine unit under test from one technical condition to another. It is shown that the existing methods do not take into account the individual characteristics and technical condition of the parts of the cylinder-piston group. To solve the problem of tribodiagnostics, it is proposed to use the developed simulation model, which allows modeling the wear process of the cylinder bushing and piston rings of a marine diesel engine and, based on the obtained results, determining the concentration of wear products issued in the used cylinder oil at different wear rates of the moving parts. The data on the actual concentration of wear products in the used cylinder oil are subsequently correlated with the simulation model results, which makes it possible to evaluate the technical condition of the parts of the engine cylinder-piston group. The article presents the results of modeling of threshold values determination of the concentration of wear products in used cylinder oil, that measure the transition of a marine diesel engine from a working condition to a malfunctioning technical condition. Practical recommendations are given on choosing threshold values for the concentration of wear products in used cylinder oil for various types of marine crosshead diesel engines and their operating conditions.


2016 ◽  
Vol 46 (7) ◽  
pp. 1200-1205 ◽  
Author(s):  
Javier Solis Estrada ◽  
José Fernando Schlosser ◽  
Marcelo Silveira de Farias ◽  
Fabrício Azevedo Rodrigues ◽  
Alfran Tellechea Martini ◽  
...  

ABSTRACT: This research evaluated the performance of a diesel engine in an agricultural tractor, using Diesel S500 (B5) and mixture with 3% (ED3), 6% (ED6), 9% (ED9), 12% (ED12) and 15% (ED15) of hydrous ethanol. Variables evaluated were the power, torque, specific fuel consumption, torque reserve, speed reserve and elasticity index of engine. Results indicated that using B5 and ED3 the values of torque and engine power not differ, in addition, with the ED3 the fuel consumption was lower than 5.92%. Using ED12, power has reduced in 2.97%, compared with B5, while their fuel consumption had no difference. With ED15, the power was lower 6.30% and the fuel consumption increase 3.77%, both compared with B5. Torque reserve value was increased with increasing the ethanol content in B5, reducing the speed reserve and elasticity index of engine. Ethanol in Diesel S500 (B5) can be used as an alternative fuel in agricultural tractor engines without presenting high changes in the performance, since the ethanol content is at low percentages, up to 12%.


2014 ◽  
Vol 554 ◽  
pp. 505-509
Author(s):  
Mohd Zaini Jamaludin ◽  
Safaruddin Gazali Herawan ◽  
Mohamed Arifin Yusmady ◽  
Ahmad Fauzi

Nowadays, biodiesel from non-edible feedstock is gaining more concern than edible oil to substitute diesel fuel. The purpose of this study is to investigate the performance of low cost single cylinder diesel engine fuelled by regular diesel and B5 biodiesel of castor and jatropha. The experiments were conducted to identify the performance of a low cost single cylinder diesel engine dynamometer, in terms of engine torque, engine power, and brake specific fuel consumption. It was found that these biodiesel can be used as the alternative fuel based on the performance of engine dynamometer, where the results show nearly similar with regular diesel.


2020 ◽  
Vol 13 (1) ◽  
pp. 202
Author(s):  
Alexandru Cernat ◽  
Constantin Pana ◽  
Niculae Negurescu ◽  
Gheorghe Lazaroiu ◽  
Cristian Nutu

Hydrogen can be a viable alternative fuel for modern diesel engines, offering benefits on efficiency and performance improvement. The paper analyses the results of a thermodynamic model developed by authors in order to study the influence of Hydrogen addition on a process like vaporization, mixture forming, and combustion at the level of diesel fuel droplets. The bi-zonal model is applied for a dual-fueled diesel engine K9K type designed by Renault for automotives. For the engine operating regime of 2000 rpm speed and 55% engine load, the diesel fuel is partially substituted by Hydrogen in energetic percents of 6.76%, 13.39%, and 20.97%, the engine power being maintained at the same level comparative to classic fueling. At Hydrogen addition, the diesel fuel jets atomization and diesel fuel droplets vaporization are accelerated, the speed of formation of the mixture being increased. Comparative to classic fueling, the use of Hydrogen leads to diesel droplets combustion intensification, with a shortened autoignition delay, reduction of combustion duration, and increase of flame radius.


Author(s):  
Liudmila Anatolievna Semeniuk ◽  
Maxim Igorevich Tarasov

The key directions of the oil aging process are closely interrelated with its fumes and this is once again confirmed by the motor experiment. The degree of oxidation of the engine oil subjected to identification by increasing the concentration of insoluble impurities identifies the thermo-oxidative destruction of the present hydrocarbons. The results of modeling the process of wear of parts of the cylinder-piston group of marine diesel are considered. Through the application of the theory of experiment planning, the range of minimum wear is revealed, the dependence is focused on the values of the quality indicators of the used fuels and lubricants, the engine boost and the amount of engine oil burn. The change in the values in the main directions of oil aging as a result of reducing its fumes was noted. There has been revealed engine oil burnout in which the operation of the diesel engine is accompanied by less carbon and varnish formation on its pistons and the wear rate of the elements of the cylinder-piston group, the engine oil being in excellent condition in terms of the composition of aging products. Oil aging rate is determined at each stage of trial, according to sample analysis. There is given the matrix of experiment planning, as well as results of its processing. There are established the equations usable in trunk diesel operation that help to analyze general and specific rate of motor oil ageing, the initial values being values of oil waste, properties of fuels and lubricants and engine forcing. Motor oil of М-14-Г2 grade (circulating system) has been recommended to use for efficient and durable operation of ship diesels with average and low boost. For high powered engines operating on deep refining fuels it is possible to use the following oil grades: М-14-Д2 (cl 20) и М-14-Д2 (cl 30) with high neutralizing and motor qualities.


2021 ◽  
pp. 45-51
Author(s):  
I.V. Parsadanov ◽  
A.G. Lal

Based on the analysis and synthesis of previously performed theoretical and practical studies, the paper proposes a concept of combustion process organization in a boxer two-stroke diesel engine at a high level of boosting. Such diesel engines are produced in Ukraine and are widely used in land, sea and rail transport, as diesel generator plants. The implementation of this concept will ensure the reduction of the thermal stress of the cylinder piston group for these diesel engines, while improving fuel efficiency. The features of the organization of the working process in a boxer two-stroke diesel engine are briefly considered. The contribution of Ukrainian, Russian and American scientists to the development and improvement of their mixing efficiency is noted. Following the purpose of the research, which determines the choice of directions for the development and implementation of technical solutions for the simultaneous reduction of fuel consumption and thermal tension of the cylinder-piston group when forcing a boxer two-stroke diesel engine, it is proposed to use the amount of released heat as a criterion for evaluating the quality of combustion. Based on the results of earlier studies, conceptual foundations for increasing the efficiency of the combustion process of a highly boosted boxer two-stroke diesel engine have been developed, which are directly related to the air supply, fuel supply, the rationale for choosing the shape of the combustion chamber are determined by the amount of heat released during combustion and the nature of its change in the crankshaft rotation angle.


Author(s):  
Şenol Durmuşoğlu ◽  
ERGİN KOSA

To logistically maintain a fuel supply is a certain issue for the military. NATO prefers single fuel concept to cancel out troubles in fuel transport and storage. To overcome this problem, kerosene-based F-34 jet fuel used in aviation has been chosen as a single fuel for a land-based vehicle in this research. In the study, feasibility of using F-34 jet fuel in a diesel engine has been investigated and the performance of the jet fuel has been compared with a conventional F-54 diesel fuel. The engine parameters of M52 such as power and torque character for both F-34 jet fuel and F-54 diesel fuel has been achieved. Also, the experiments on diesel engine including fuel consumption measurements under certain engine speeds and torques has been done for both fuels. Moreover, wear on fuel pumps of Magirus Unimog and M.A.N truck has been measured during long term tests operating with F-34 and F-54 fuels, respectively. It is observed that there is no certain difference in engine power and torque character between using F-34 and F-54 fuel.


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