Combustion chamber wall influences on the vaporisation, mixture formation and combustion in DI diesel engines with a small combustion chamber

MTZ worldwide ◽  
2002 ◽  
Vol 63 (9) ◽  
pp. 26-30
Author(s):  
Christian Fettes ◽  
Tilo Schulze ◽  
Alfred Leipertz ◽  
Hans Zellbeck ◽  
Detlev Potz
MTZ worldwide ◽  
2002 ◽  
Vol 63 (7-8) ◽  
pp. 35-38
Author(s):  
Christian Fettes ◽  
Tilo Schulze ◽  
Alfred Leipertz ◽  
Hans Zellbeck ◽  
Detlev Potz

2019 ◽  
Vol 20 (7) ◽  
pp. 805-816 ◽  
Author(s):  
Akio Kawaguchi ◽  
Yoshifumi Wakisaka ◽  
Naoki Nishikawa ◽  
Hidemasa Kosaka ◽  
Hideo Yamashita ◽  
...  

Cooling heat loss is one of the most dominant losses among the various engine losses to be reduced. Although many attempts to reduce it by insulating the combustion chamber wall have been carried out, most of them have not been successful. Charge air heating by the constantly high temperature insulating wall is a significant issue, because it deteriorates charging efficiency, increases the emissions of soot and NOx in diesel engines, and promotes the knock occurrence tendency in gasoline engines. A new concept heat insulation methodology which can reduce cooling heat loss without heating the charging air has been developed. Surface temperature of insulation coating on the combustion chamber wall changes rapidly, according to the quickly changing in-cylinder gas temperature in each engine stroke. During the compression and expansion stroke, the surface temperature of the insulation coating goes up rapidly, and consequently, the heat transfer becomes lower by the reduced temperature difference between the surface and the gas. During the intake stroke, the surface temperature goes down rapidly, and it prevents intake air heating from the wall. To realize the above-mentioned functionality, a thin coating layer with low thermal conductivity and low heat capacity was developed. It was applied on the pistons of diesel engines, and showed improvement in thermal efficiency. It also showed a reduction of unburnt fuel emission in low temperature engine starting condition. The energy balance analysis showed reduction of cooling heat loss and, on the contrary, increase in the brake power and the exhaust loss.


Author(s):  
Serhii Kovalov

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.


2017 ◽  
Vol 46 (1) ◽  
pp. 49-53
Author(s):  
R. Bhaskar Reddy ◽  
S. Sunilkumar Reddy

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.


1992 ◽  
Author(s):  
Keh C. Tsao ◽  
Yu Dong ◽  
Yong Xu ◽  
D. Gruenwald ◽  
E. Phillips

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