F2008-07-013
Research of the Air Filter in the Desert Heavy Duty Truck
In order to develop the underground resources of desert, the quantity demanded for heavy duty truck and engineering machine specially utilized in desert are rapidly increasing. Because of operating in desert, the most difficult problem of those machines is early engine worn out.
Authors have been to the Taklimakan Desert of China Xinjiang, to research and investigate operating condition of heavy duty truck and engineering machine at real desert, and to measure the percentage of the dust at different heights(including the condition of motorcade driving in line). The measured results and interrelated data from Arab desert, Australia desert, and Libya desert are the references in researching air filter of desert heavy duty truck.
There are two requirements for a desert air filter: first, high filter efficiency, viz. the filter medium which make main element meet heavy-duty air filtration and itīs filter efficiency exceed 99.5%; second, long operating life, viz. the prefilter efficiency should exceed 93%. The main research object of desert air filter is the prefilter.
After researching and analyzing the relative merits of different type prefilters, we think the most suitable prefilter is made up of axial-flow cyclone pipe.
The cyclone pipe with large flow is one of the main subjects of our research. Via optimum design to each parameter of cyclone pipe, and utilizing 7 cyclone pipes as a unit of test research, and three types of cyclone pipe selected has been tested. At last, we choice the cyclone pipe is with 35mm inside diameter, with 4 guide vanes, the helical angle of the vane is 30 degrees, each guide vane is a quarter of circle, and with no overlap angle between two adjacent vanes. So it could be manufactured easily, such as compression moulding with plasticate. According to inspection, it got excellent performances. When flow rate of one cyclone pipe is 32m3/h, its separating dust efficiency reaches 95%. The pressure loss is 1.6kPa only.
The automatic dust exhausting installation of the prefilter is one of the requirement of desert air filter. The paper discussed dust exhausting scavenged in considerable detail. If the automatic dust exhausting can be executed by diesel exhaust scavenged, then it is best to fix the main filter element and cyclone pipe assembly as `Tī form. If can not, according to test result, the main filter element and cyclone pipe assembly should be arranged in parallel structure, and fixed in horizontal situation. Then it can achieve automatic dust exhausting of prefilter.
A new desert air filter for 370PS supercharged diesel engine-SK3052T filter in which the prefilter is made up of 50 new cyclone pipes has got high performances, viz. total efficiency of the filter reaches 99.7%, and prefilter efficiency reaches 95.5%, and dust holding capacity reaches 35.26kg.
According to characteristic of the desert environment, we also give the advices for the type and height of desert air filterīs inlet.
Session: Truck Concepts