INVESTIGATION ON EVAPORATIVE EMISSION FROM A GASOLINE POLYCARBONATE FUEL TANK

It is estimated that about 15 to 20 percent of the vehicle hydrocarbon (HC) emission were due to evaporation of fuel. Hence a need was felt to understand the extent of evaporative emission from gasoline fuel system. A polycarbonate fuel tank that is predominantly used in two wheeled vehicles is considered for study. Emission can surface to atmosphere in three modes; diffusion through fuel tank wall, escaping through vent in tank and when fuel tank cap is opened for refueling. The average temperature condition which prevails in south India which is in the range of 27o C to 34oC was considered. From which temperatures which were at proximity to peak high and low day time were chosen. The complete set up was placed in open atmosphere to replicate the working environment. The emission constituents and its levels were measured by conducting the test particularly for averaged out day time high and low temperature condition. Further diffusion test was conducted within a range of 34oC to 36oC, this temperature is considered to be range of maximum temperature which prevails in south India. From which a temperature was chosen and the test was conducted. This comparative study gives an indication of emission and its quantity from the fuel tank at the ambient temperature