Acoustic–structure modeling and analysis of an engineering machinery cab based on the hybrid method and experimental investigations

Abstract

To study the mid-frequency acoustic-structure in the cab of construction machinery vehicle, a prediction model was established based on the FE-SEA hybrid method. Model parameters, such as the modal density, the internal loss factor and the coupling loss factor of each subsystem, were calculated by the theoretical methods. The sound pressure excitation and vibration excitation of the model obtained through the real vehicle experimental tests and the mid-frequency vibration characteristics of the cab in the frequency range of 100-800 Hz under composite excitation were studied. In order to verify the accuracy of the hybrid model, the full FE acoustic-structure coupling model of the cab was also established, and the modal calculation of the cab was carried out. In the end, the two methods were verified by the real sound pressure test in the cab. The results show that the hybrid model has a great deviation from the experimental results in the low-frequency region of 20-80 Hz, and the calculation accuracy is lower than that of the FE model. The prediction accuracy starts to rise when frequency is higher than 80 Hz; especially in the mid-frequency region of 100-800 Hz, the hybrid model accuracy reaches the highest with results basically consistent with the experiment. In addition, in the high-frequency range, higher than 800 Hz, the prediction results also agree well with the experimental ones. It should be pointed out that the hybrid model cannot accurately capture the peak value of the response in the noise prediction, but it can guarantee the accuracy, improve the calculation efficiency and improve the prediction accuracy in the mid-frequency region.

Sound Field Optimization of Construction Machinery Cab Structure based on Ergonomics and Mathematical Modeling

“…Similar to structural modes, cavity modes also have mode shapes and natural frequencies. Cavity mode shapes represent the distribution of sound pressure generated by sound wave transmission, and natural frequencies represent the resonant frequencies of cavity [14]. In the design stage of vehicle cab, the position beside the ears of the driver and occupant should be placed in the node-line position of the acoustic cavity mode as far as possible, so that the occupant can be placed in a good acoustic environment [15].…”

“…Therefore, many manufacturers of passenger vehicles, construction machinery and aircraft have invested a lot of manpower, material resources and financial resources to study noise control, among which noise control in closed sound chamber is a hot research topic at home and abroad. For example, the 2000/14 / EC Directive of the European Parliament and the Council of Europe and the GB 16710.1.2010 limit standard of construction machinery noise have clear requirements on the sound pressure level at the driver's ear [1]. In the field of defense industry, the noise in armored vehicles, military transport planes, ships and so on directly affects the comfort of combatants, thus affecting their combat effectiveness.…”

Acoustic Energy Harvesting From Sonic Crystals with Non-square Lattices Using Piezoelectric Patch

“…A defect is created by removing a rod from regular sonic crystals and can act as a resonance cavity. If the piezoelectric is placed inside an acoustic crystal defect, the conversion of acoustic energy to electrical energy takes place at the resonance frequency of the cavity [13][14][15]. Wu et al [16], presented acoustic energy harvesting using sonic crystal.…”