Study On Sound-reduction Properties Of The Counter-Phase And Split-Gas Rushing Muffler For Single-Cylinder Diesel Engine

In this paper, the acoustic properties of a counter-phase and split-gas rushing muffler on single-cylinder diesel engine was simulated by3D acoustic software and validated by corresponding experiments.The3D model and meshing of counter-phase and split-gas rushing muffler has been established, then simulated with acoustic software. Taking the single-cylinder diesel CG25as the experimental engine, the experimental validation for the simulation result was performed, which provides a theoretical basis for the design and optimization of the new mufflers, and following conclusions are obtained:1. Under the reasonable boundary conditions, the simulation result indicated that counter-phase and split-gas rushing muffler was obviously effective in noise control. At the same time, the uniform distribution of the sound pressure under the frequency of110Hz proved that the new muffler has very good performance for low-frequency noise reduction.2. The calculation on transmission loss of acoustic property indicated the obvious effect of counter-phase and split-gas rushing muffler on noise reduction, especially under the frequency of110Hz, also proved the reasonability of using U-shaped tube.3. The tested results show that, under rated speed of diesel engine, the insertion loss of original muffler was7.7dB(A), while the new muffler’s was13.2dB(A), the insertion loss can be lowered by more than1.5times. Meanwhile, the transmission loss of muffler was obtained by5.5dB(A), which was more obvious under lower frequency.Both simulation and experiment proved that the counter-phase and split-gas rushing muffler has a good performance for low-frequency noise reduction.