In this present work a study about the effect of varying the combustion chamber geometry i.e. providing the curved tangential groove on the piston crown in the cylinder was investigated for the air swirl, squish, tumble in the combuston chamber by using CFD software, this improving the performance, emission and combustion characteristics of a single cylinder direct injection diesel engine by using biodiesel. In order to achieve the different swirl intensities in the cylinder, three design parameters have to changed: the cylinder head, piston crown, and inlet duct. In this way, the piston crown is modified i.e.alteration of combustion chamber to enhance the turbulence in the cylinder. In this ...view middle of the document...
Pongamia Pinnata locally known as Karanja is chosen for this study. The seeds are largely exploited for extraction of a non-edible oil, commercially known as ‘KARANJAOIL’ well recognized for its medicinal properties and also used in the manufacture of soap. Leaves are used as fodder and green manure. The wood of this tree is used as fuel throughout the country and also used for construction, tool handles and agricultural implements.
2. Experimental setup and methods
Pongamia Pinnata locally known as Karanja is chosen for this study. The properties of this oil which is compared with diesel is given below in table 2.1
2.1 Properties of Biodiesel Fuels
Property Pongamia Biodiesel ASTM standards Diesel
Calorific value MJ/Kg 37-40 - 44.03
Density Kg/m3 0.87 - 0.830
Flash point ̊ C 186 130̊ C min 35̊ C (min)
Sulphur content % 0.0015 0.05 0.25 (max)
Viscosity 5.867 1.9-6.0 cst 2-5 cst
Cetane number 50-52 - 45-50
The experimental set up for measuring performance, emission and combustion
Parametersis described below. The schematic representation of the experimental set up is shown in fig. It consists of a single cylinder diesel engine, eddy current dynamometer, crypton 5 gas analyzer and fuel measuring tube.
The engine used in test rig is a Kirloskar Model SV1, single cylinder, four stroke, Water cooled, direct injection type, diesel engine. To reduce the temperature of the cylinders and the lubricant, the cooling system of the engine is connected to a cooling water tower by means of a cooling-water pipe line. The specifications of engine used for this study are given below in table 2.2
Table 2.2 Engine Specification
TYPE Single cylinder 4s C.I.engine (Kirloskar)
Compression ratio 17.5:1
Brake Power 5.2KW
Speed 1500 RPM
Injection timing 23̊ b TDC
Dynamometer Eddy current Dynamometer
Cooling system Water cooled
2.2 Measurement Range of Crypton Exhaust Gas Analyzer
This analyzer is used to find out emission in exhaust gases coming from the engine such as hydro carbon (HC), carbon monoxide (CO), carbon di oxide (CO2) , and oxygen (O2).
• CO : 0 – 10% vol.
• HC : 0 – 10000 ppm
• CO2 : 0 – 20% vol.
• NOX : 0 – 5000 ppm
• O2 : 0 to 25%
AVL Smoke meter is used to measure the smoke from the engine which was connected through the exhaust pipe of the engine. It measures the exhaust smoke level by using the method of spot filtering principle. The smoke value measured by this instrument ranges from 0 to 100.It is either denoted as Hatridge smoke number.
2.4 Valve timing
Inlet valve Opens bTDC - 4.5 deg
Inlet valve closes aBDC - 35.5 deg
Exhaust valve opens bBDC - 35.5 deg
Exhaust valve closes aTDC - 4.5 deg
The modified pistons are used for this...