| The rapid development of science and technology,the domestic construction machinery development is very high-speed.As the increase in the output power of construction machinery,the noise is also increasing and the noise of construction machinery has begun to be taken seriously.At present,there are many researches on the noise and noise reduction methods of excavators,but the research is not particularly detailed,and the better method of noise control is still to be researched.This paper investigates the noise situation in the cab when the excavator is running,and puts forward a new noise reduction method based on the existing noise control method.Finally,the total noise control scheme is proposed to analyze the noise reduction effect.In this paper,the finite element model of the excavator body structure and the finite element model of the cab cavity are established by using Hypermesh.The modal and acoustic solid coupling modes are analyzed.According to the vibration excitation and air excitation calculation of the cab structure within 1000 Hz vibration response,and carried out the analysis.Using the Virtual.Lab software,the sound field within 1000 Hz of the cab is calculated according to the coupled acoustic finite element method.The sound field distribution cloud image is solved and the area with large sound pressure level in the cab is analyzed.The sound pressure response curves of the three sites near the driver are calculated and the frequency band of the sound pressure level is analyzed.The sound pressure response curve obtained by the simulation is compared with the measured sound pressure response curve,and the accuracy of the simulation analysis is confirmed.The contribution of each plate in the cab to the sound pressure level of the field is analyzed,and the plate with large contribution is determined.The acoustic transmission characteristics of the cab are analyzed,the acoustic map and function of the cab are calculated,the larger area of the ATV function is analyzed,and the sound field inside the cab is analyzed according to the acoustic transfer theory.The influence of the acoustic parameters of the porous sound-absorbing material on the noise absorption coefficient was analyzed by numerical calculation.The sound absorption performance of the composite sound-absorbing plate was tested,and the best sound absorption structure was obtained.The improvement of the reinforced skin structure in the cab is carried out.The sound insulation characteristics of the reinforced skin,the well shape and the rice-shaped skin structure are compared and analyzed,and the optimal skin structure type is obtained.The influence of different structural parameters of honeycomb plate structure on noise control is analyzed,and the advantages and disadvantages of thick honeycomb and thin honeycomb are analyzed.The noise reduction effect of the sound absorption structure and the meter-shaped plate structure on the sound field inside the cab is analyzed respectively.Finally,the overall noise control scheme is proposed to solve the sound field after the total noise control scheme of the cab and the total noise reduction program noise reduction effect. |
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