Sound and Vibration Levels of CI Engine with Synthetic Kerosene and n -Butanol in RCCI

Diesel engines provide the necessary power for accomplishing heavy tasks across the industries, but are known to produce high levels of noise. Additionally, each type of fuel possesses unique combustion characteristics that lead to different sound and vibration signatures. Noise is an indication of vibration, and components under excessive vibration may wear prematurely, leading to repair costs and downtime. New fuels that are sought to reduce emissions, and promote sustainability and energy independence must be investigated for compatibility from a sound and vibrations point-of-view also. In this research, the sound and vibration levels were analyzed for an omnivorous, single cylinder, CI research engine with alternative fuels and an advanced combustion strategy, RCCI. The fuels used were ULSD#2 as baseline, natural gas derived synthetic kerosene, and a low reactivity fuel n-Butanol for the PFI in the RCCI process. This combination of fuels was never analyzed from NVH point of view in RCCI mode. The sound and vibration signatures were measured using a B&K condenser type microphone and a piezoelectric, triaxial accelerometer. The data were analyzed with CPB and FFT Analysis, and Angle Domain Analysis with B&K Pulse platform software. The tests were conducted at 1500 rpm and 4 bar IMEP load, with 40% EGR, and 65% by mass PFI of n-Butanol. The COV for RCCI with S-8 and ULSD#2 were 5.14 and 4.80, respectively. The max values of the heat release for RCCI was 97 and 112 J/CAD for S-8 and ULSD#2, respectively. The results indicated that a difference of 5.5 dB(A) was achieved between RCCI with S-8, and RCCI with ULSD#2.