Analysis of the thermal state of spray nozzles

Abstract

Diesel engines have been widely used for motor-and-tractor equipment. A nozzle is the most important device of the diesel power supply system. Analysis of the thermal state of spray nozzles provides the information on the operation process. It provides a basis for improving the internal combustion engine systems. The thermal state of spray nozzles has a significant impact on the efficiency and reliability, it can be estimated by an experimental or theoretical calculation method. In relation to the unification of pintle and multi-jet nozzles regarding a swirl-chamber diesel, the analysis of the thermal state was conducted. The calculation determined the distribution of the fuel temperature during the passage of the sprayer in a steady state mode at the nominal load. The highest design temperature of the spray nozzle was 192-220 °C. At the same time an increase in the pressure of fuel injection from 13 to 17 MPa reduced the temperature by 15-19 °С °(from 215 to 198 °С). Low-density fuel significantly reduced the design temperature along the entire length of the sprayer by increasing heat dissipation from the nozzle to the fuel. So, the design temperature at the injection pressure of 15 MPa was 212 °С for the fuel with the density of 850 kg/m³ and 199 °С for the fuel with the density of 810 kg/m³.