Abstract
In order to ensure the stable operation of a dual-fuel engine with alcohol, the combustion process and the control system of a dual-fueled tractor engine were evaluated by measuring the cylinder pressures. Compared to the operation with diesel fuel alone, the mean of the maximum combustion pressures increased by 9.5 percent, and the standard deviation of them amounted to 5.7 times with dual-fuel operation. The spectral analysis for the fluctuant components of the maximum combustion pressures was carried out. It became clear that the frequency range of the strongest combustion fluctuation was below 0.2 Cycle/Cycle that was a relative long cycle. It was also concluded that the cause of the combustion fluctuation in this range was the ill-suited control of alcohol flow rate. This problem was able to be solved by adopting the appropriate parameters for a control of alcohol flow rate.
