The possibilities of early fault detection of engines

The results of investigation of 1,9 TDI engine (285 Nm, 85 kW, type AJM without any modification) equipped with injection units supplied conventional diesel fuel (ON) or B100 fuel (RME) have been presented in article. Investigations have been realized at the engine speed of 2000 rpm and variable load within the range of 0 to 275 Nm. The pressure, temperature and heat release velocity runs have been subjected to analysis. Particular attention has been paid to the release of the heat used for the effective work and internal energy increase of the working medium (enthalpy) during combustion inside the engine cylinder versus the crank angle for both investigated fuels. It was found among the others that mentioned fuels differ in the heat release, heat velocity and the maximal combustion temperature, which for the B100 fuel is bigger than for the conventional diesel fuel. Bigger combustion dynamics of tested biofuel (compared with standard diesel fuel) results higher concentrations of Nitrogen Oxides NOx in exhaust gases. The easiest way is of course the use of the later start of fuel injection biofuels and/or increase the exhaust gas recirculation EGR. These treatments, however, result in a worsening of the energy performance of the engine. It was concluded also that the combustion of RME works properly at higher engine loads. Then reduce the negative difference between the combustion of biofuel (RME) and standard Diesel fuel.