Latvian Maritime academy

Here, we review the special features of the combustion efficiency in the diesel engine with anadjustable turbocharger prototype with vaneless turbine volute in mode with P e = 67.8 kW andn = 1250 rpm. The reduction of the effective cross-section area of the end of the turbine voluteacceleration section A improves the in-cylinder mixture formation and combustion processes in thismode. It is confirmed by the shape of the averaged indicated diagram shown in Figure 5.Figure 5. Dependence of temperature and pressure in the cylinder of the engine on the mode withP e = 67.8 kW and n = 1250 rpmThe change in the main indices of the experimental diesel engine in relation to the value of effectivecross-section A, is shown in Figure 6. As seen in the figure, a reduction in the value of A leads toimprovement of all indices that characterize the combustion efficiency. Here, SCF improved by 4.5%g/kWh, the Lambda increased from 1.26 to 1.38 (Figure 6 b), and the indicated efficiency rose by 3.5%(Figure 6 f).Therefore, in the case of studded mode, the efficiency of turbine adjustment with vaneless turbinevolute is mostly evident in modes with high load and low engine speed. In such modes it is necessary todecrease the value of A thus increasing the Lambda and improving the quality of the combustionefficiency as seen in Figure 6.5.2. Results of experimental investigation of diesel engine with the prototype of VGT running ontorque and power modesExperimental investigations were held on a four cylinder diesel engine specified in section 3. Enginewas running on a torque and power curve modes. Adjustment of VGT was conducted in the range ofengine speeds from 1250 to 1800 rpm. Two algorithms of VGT adjustment were used: to get a constantpower curve for diesel engine and a constant torque curve for it.56