الفهرس Only 14 pages are availabe for public view
 |  | from | 109 |  |  |
| | | from | 109 | | |
Abstract
Described in this thesis are the results of an experimental study concerning the effect of combustion chamber shape on combustion and working parameters of diesel engines. A single cylinder, four stroke, water cooled, direct injection diesel engine was used. The normal geometry of the combustion chamber of the engine under investigation was shaped as a herru. -sphere bowl-in piston, The original combustion chamber shape was modified using small additional parts of equal volumes. These parts were either a segment of a sphere or a cone with different apex angles CQO, 9O and 1 £O 3, each of which is fitted in the axial center of the hemi-sphere combustion chamber.
The engine parameters examined were combustion chamber geometry, engine load and engine speed. The effect of the previous parameters on ignition delay period, combustion time, mean rate of pressure rise, heat release rate and engine brake thermal efficiency was investigated.
The technique used in this study was pressure signal recording from a Piezo electric transducer simultaneously with a pick-up degree marker sensor using a double-beam oscilloscope and universal camera.
The experimental results showed that there are great effects of combustion chamber geometry on combustion process and engine per for mance A modified combustion chamber with an additional part from a cone with apex angle of 12O or an additional part from a segment of sphere obtained less ignition delay period, lower or moderate mean rate of pressure rise, lower premixed peak heat release rate and improved brake thermal efficiency compared with the original or other modified combustion chambers..