Development of Microwavable Diesel Soot Filters For Diesel Engine Exhaust System

This paper offers the results from an experimental analysis for diesel soot oxidation alternative by using induction spring coils in microwaves. Soot particles are released from diesel exhaust systems because of the inadequate burning of hydrocarbons. The oxidation temperature of soot particles is extremely high, which ranges from 6000C – 7000C. Induction coil is used as the element to trap and combust soot because it is able to heat up through induced current method when it interacts with electromagnetic waves. When exposed to microwaves, the induction spring coils made of mild steel, which is a conductive material are able to experience steady and quick heating to very high temperatures. Therefore, the induction coils are anticipated to attain the necessary soot oxidation temperature. From previous research work, it is proven that a larger loop diameter and smaller wire diameter achieves the minimum temperature in the shortest time. The dimension of the spring coils used in this project 0.1cm as the wire diameter (d=0.1cm), 1.5cm as the loop diameter (d=1.5cm), 20 number of turns (N=20) and 4.2cm as the total length of the coil (L=4.2cm). The induction coils accumulated with soot particles released from the diesel engine combustion were then exposed to microwaves at 80% power levels for a period of 180 seconds. The weights of the induction coils were measured before and after the soot accumulation procedure in order to determine the weight of the soot collected. Then, the weights of the induction coils were measured before and after the soot oxidation procedure to determine the amount of soot oxidized. During the experiment, an infrared (IR) thermometer was used to measure the temperature of the induction coils every 30 seconds time interval for 180 seconds. From the results obtained, it is proven again that the smaller wire diameter and bigger coil diameter is able to achieves the minimum temperature in the shortest time.