Effects of Diesel Injector Nozzle Hole Deposit on Fuel Injection and Spray Characteristics

Abstract

The nozzle hole deposit formation is investigated by the test rig in which deposit formation can be accelerated at various injection pressures, injection durations, and nozzle tip temperatures. The rotational speeds of the fuel supply pump are varied to obtain the different times between injections. The Bosch method and the constant volume chamber with a high speed video camera are used to investigate the effects of deposit in the nozzle hole on injection rate and spray characteristics. The results show the longer time between injections promotes the nozzle hole deposit and affects both the fuel injection and the spray characteristics.