33
Vegetable Oils
of oxygen molecules, is also taking part in the combustion. Hence, while
using neat rubber seed oil, higher exhaust temperature was attained;
this indicates more energy loss in this case. The exhaust gas temperature
increases with increase in load for all tested fuels. The NO x emission is
directly related to the engine combustion chamber temperatures, which in
turn was indicated by the prevailing exhaust gas temperature. Vegetable oil
engines have the potential to emit more NO x as compared to that of dieselfueled engines.
2.4.2 endurance Tests
Endurance tests are conducted to evaluate the effect of fuel on engine components like injectors, piston ring wear, engine combustion chamber deposits, and engine lubricant wear metal analysis. Vegetable oil can be produced
locally and can be effectively used in rural areas for water pumping and
power generation. For that purpose, diesel engines are suitable for electric
generator application used in agricultural water pumping is selected. The
engine ran continuously at full load conditions using 50:50 blend (rubber
seed oil:diesel) and compared with that of diesel. The engine cylinder head is
dismantled for visual inspection and quantitatively analyzed for the carbon
particles deposited.
The combustion chamber region of the cylinder head showed uniform, flat
carbon buildup for both fueled engines. No differences in the conditions of
the intake and exhaust valve seats were detected between the blend and diesel. A thin layer of carbon particles is distributed over the circumference of
the valve seats. The valve seats, as well as the valve faces, showed the peening caused by hard particles released from combustion chamber deposits.
Carbon buildup on the top surface of the piston is not uniform.
Figures 2.6 and 2.7 show the carbon deposits on the cylinder head of the
diesel-fueled and blend-fueled engine conditions, respectively. There was
more carbon deposits on the cylinder head of the blend-fueled engine than
that of the diesel-fueled engine. A quick carbon buildup of carbon deposits
on the blend-fueled engine injector nozzles is observed. Incomplete combustion had promoted the formation of additional solid residues, which were
deposited on the combustion chamber walls and cylinder head (Ramadhas,
Jayaraj, and Muraleedharan 2005b).
Figures 2.8 and 2.9 shows carbon deposits on the piston surface of
the diesel-fueled engine and blend-fueled engine, respectively. More
deposits were formed with vegetable oil blend-fueled engine than that
of diesel. More carbon deposits formed due to the incomplete combustion of the rubber seed oil diesel blend. The higher viscosity of fuel that
leads to poor atomization characteristics causes incomplete combustion
of fuel. Moreover, the gumming nature of vegetable oil formed carbon
particles on the wall of the combustion chamber (Ramadhas, Jayaraj, and
Muraleedharan 2005b).
Vegetable Oils
of oxygen molecules, is also taking part in the combustion. Hence, while
using neat rubber seed oil, higher exhaust temperature was attained;
this indicates more energy loss in this case. The exhaust gas temperature
increases with increase in load for all tested fuels. The NO x emission is
directly related to the engine combustion chamber temperatures, which in
turn was indicated by the prevailing exhaust gas temperature. Vegetable oil
engines have the potential to emit more NO x as compared to that of dieselfueled engines.
2.4.2 endurance Tests
Endurance tests are conducted to evaluate the effect of fuel on engine components like injectors, piston ring wear, engine combustion chamber deposits, and engine lubricant wear metal analysis. Vegetable oil can be produced
locally and can be effectively used in rural areas for water pumping and
power generation. For that purpose, diesel engines are suitable for electric
generator application used in agricultural water pumping is selected. The
engine ran continuously at full load conditions using 50:50 blend (rubber
seed oil:diesel) and compared with that of diesel. The engine cylinder head is
dismantled for visual inspection and quantitatively analyzed for the carbon
particles deposited.
The combustion chamber region of the cylinder head showed uniform, flat
carbon buildup for both fueled engines. No differences in the conditions of
the intake and exhaust valve seats were detected between the blend and diesel. A thin layer of carbon particles is distributed over the circumference of
the valve seats. The valve seats, as well as the valve faces, showed the peening caused by hard particles released from combustion chamber deposits.
Carbon buildup on the top surface of the piston is not uniform.
Figures 2.6 and 2.7 show the carbon deposits on the cylinder head of the
diesel-fueled and blend-fueled engine conditions, respectively. There was
more carbon deposits on the cylinder head of the blend-fueled engine than
that of the diesel-fueled engine. A quick carbon buildup of carbon deposits
on the blend-fueled engine injector nozzles is observed. Incomplete combustion had promoted the formation of additional solid residues, which were
deposited on the combustion chamber walls and cylinder head (Ramadhas,
Jayaraj, and Muraleedharan 2005b).
Figures 2.8 and 2.9 shows carbon deposits on the piston surface of
the diesel-fueled engine and blend-fueled engine, respectively. More
deposits were formed with vegetable oil blend-fueled engine than that
of diesel. More carbon deposits formed due to the incomplete combustion of the rubber seed oil diesel blend. The higher viscosity of fuel that
leads to poor atomization characteristics causes incomplete combustion
of fuel. Moreover, the gumming nature of vegetable oil formed carbon
particles on the wall of the combustion chamber (Ramadhas, Jayaraj, and
Muraleedharan 2005b).