Effects of Relative Combustion Chamber Diameter on Performance and Cylinder Head Thermal Loading of Open Type Combustion Chamber Diesel Engines

The article describes the characteristics of thermal loading of the cylinder covers of transport diesel engines during their conversion to marine diesels. The engines of the CHN14/14 type produced by the Yaroslavl Motor Plant are proposed as promising for use in marine power plants. A special feature of the engine design is the individual four-valve cylinder heads, which have a complex geometric shape. The conversion of automobile engines, the cylinder heads of which were made of aluminum alloys, to marine ones is accompanied by an increase in the degree of their acceleration. The cylinder heads in operation experience significant thermal and mechanical loads, which causes the need for increased requirements for the materials of the cylinder heads. The rational choice of the cylinder head material is one of the most important tasks to be solved when upgrading and boosting engines. Experience in the operation of marine diesel engines shows that in order to ensure the required reliability under prolonged exposure to elevated temperatures due to forcing, it is necessary to choose cast iron as a structural material. A three-dimensional model of the cylinder head is developed. When performing the calculations, the boundary conditions are justified, taking into account the local nature of the distribution of thermal and mechanical effects on the diesel cylinder head. As a result of numerical modeling, the stress-strain states of cylinder heads made of high-strength cast iron, ductile iron and cast iron with vermicular graphite are determined and analyzed. There has been proved the preference for using cast irons with vermicular graphite, which have satisfactory casting and physical and mechanical properties. The advantages of using cast iron with vermicular graphite include a decrease in the temperature of the cylinder head in the area of the inter-valve bridge. The possibility of increasing the engine power from 330 to 560 kW when replacing aluminum alloys with cast iron with vermicular graphite for the manufacture of cylinder heads is proved.

Download Full-text

DEVELOPMENT OF THE COMBUSTION CHAMBER OF GAS ENGINE, CONVERTED ON THE BASIS OF DIESELS D-120 OR D-144 ENGINES TO WORK FOR ON LIQUEFIED PETROLEUM GAS

Avtoshliakhovyk Ukrayiny ◽

10.33868/0365-8392-2019-3-259-2-8 ◽

2019 ◽

pp. 2-8

Author(s):

Serhii Kovalov

Keyword(s):

Combustion Chamber ◽

Compression Ratio ◽

Diesel Engines ◽

Combustion Engine ◽

Motor Fuel ◽

Liquefied Petroleum Gas ◽

Gas Engine ◽

Chamber Volume ◽

Motor Fuels ◽

Dynamic Cycle

The expediency of using vehicles of liquefied petroleum gas as a motor fuel, as com-pared with traditional liquid motor fuels, in particular with diesel fuel, is shown. The advantages of converting diesel engines into gas ICEs with forced ignition with respect to conversion into gas diesel engines are substantiated. The analysis of methods for reducing the compression ratio in diesel engines when converting them into gas ICEs with forced ignition has been carried out. It is shown that for converting diesel engines into gas ICEs with forced ignition, it is advisable to use the Otto thermo-dynamic cycle with a decrease in the geometric degree of compression. The choice is grounded and an open combustion chamber in the form of an inverted axisymmetric “truncated cone” is developed. The proposed shape of the combustion chamber of a gas internal combustion engine for operation in the LPG reduces the geometric compression ratio of D-120 and D-144 diesel engines with an unseparated spherical combustion chamber, which reduces the geometric compression ratio from ε = 16,5 to ε = 9,4. The developed form of the combustion chamber allows the new diesel pistons or diesel pistons which are in operation to be in operation to be refined, instead of making special new gas pistons and to reduce the geometric compression ratio of diesel engines only by increasing the combustion chamber volume in the piston. This method of reducing the geometric degree of compression using conventional lathes is the most technologically advanced and cheap, as well as the least time consuming. Keywords: self-propelled chassis SSh-2540, wheeled tractors, diesel engines D-120 and D-144, gas engine with forced ignition, liquefied petroleum gas (LPG), compression ratio of the internal com-bustion engine, vehicles operating in the LPG.

Download Full-text

INVESTIGATION ON THE PERFORMANCE OF FLAXSEED BIODIESEL BLENDS WITH TIO2 COATED PISTON ON A FOUR STROKE DI DIESEL ENGINE

Journal of Mechanical Engineering ◽

10.3329/jme.v46i1.32523 ◽

2017 ◽

Vol 46 (1) ◽

pp. 49-53

Author(s):

R. Bhaskar Reddy ◽

S. Sunilkumar Reddy

Keyword(s):

Combustion Chamber ◽

Fuel Economy ◽

Diesel Engines ◽

Canola Oil ◽

Alternative Fuels ◽

Flaxseed Oil ◽

Suitable Alternative ◽

Petroleum Resources ◽

Di Diesel Engine ◽

Alternate Fuels

Diesel engines are being used extensively for fuel economy but due to gradual depletion of Petroleum resources and increase in exhaust emissions, there is an urgent need for suitable alternative fuels for the diesel engines. As our country is an agricultural country, if the alternate fuels are produced by our farmers it will be beneficial for the country and the farmers also. In recent studies, researchers studied various vegetable oils like canola oil, alovera oil, soya been oil, flaxseed oil and hone oil etc. Out of all flaxseed oil play an important role as an alternative fuel. But the properties of flaxseed oil are not suitable for the usage in the existing diesel engines without blending with diesel fuel. The performance of the engine depends on the combustion phenomenon and it further depends on the amount of heat retained in the combustion chamber. Hence the present work is planned accordingly to develop an insulated engine by coating the piston with TIO2material. So that more amount of heat will be retained in the combustion chamber which aids the combustion. Further the performance of flaxseedbiodiesel blend namely B10, B20, B30 and B40 are tested and the results are mentioned accordingly.

Download Full-text

Investigation of Probable Combustion Chamber Configurations for High Output D.I. Diesel Engines

10.4271/921729 ◽

1992 ◽

Cited By ~ 1

Author(s):

Keh C. Tsao ◽

Yu Dong ◽

Yong Xu ◽

D. Gruenwald ◽

E. Phillips

Keyword(s):

Combustion Chamber ◽

Diesel Engines ◽

High Output

Download Full-text

INCREASING THE RESOURCE OF DIESEL CYLINDER HEADS BY IMPROVING THE TECHNOLOGY OF THEIR RESTORATION

SCIENTIFIC LIFE ◽

10.35679/1991-9476-2020-15-7-950-957 ◽

2020 ◽

Vol 15 (7) ◽

pp. 950-957

Author(s):

G.D. Mezhetskiy ◽

◽

V.A. Strelnikov ◽

Keyword(s):

Diesel Engines ◽

Thermal Loading ◽

Theoretical Calculations ◽

Operating Conditions ◽

Advanced Technology ◽

Temperature Fields ◽

Cylinder Block ◽

Diesel Cylinder ◽

Thermal Intensity

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.

Download Full-text