Abstract: After establishing 3-dimension finite element model for 3 t forklift cab structure and the acoustic finite element method for the interior acoustic field inside the cab, structural modal analysis and acoustic modal analysis are carried out respectively for the cab. The displacement response data gained from dynamic response analysis offer boundary condition for following acoustic field analysis. Spectrum analysis of SPL (sound pressure level) in the interior field, especially SPL at ear position was carried out. Contributions to the sound field from vibration of each cab panel are analyzed to find out the main sources for the peak value of SPL as reference for noise control purpose.

Key words: acoustics , cab , modal analyses , FEM , panel contribution

摘要： 建立3 t叉车驾驶室的三维有限元模型，进行结构模态分析；再建立驾驶室声学有限元模型，进行声学模态分析，初步了解驾驶室的声场。对驾驶室进行谐响应分析，得到位移响应，为后续声场提供边界条件。用有限元法进行驾驶室内部声学特性研究，对驾驶员耳旁声压进行分析，得出驾驶室内声场的声学特性。在计算出场点声压频率响应的基础上，在峰值频率处进行面板贡献量分析，找出产生峰值声压的主要来源，为降低驾驶室内噪声提供依据。

关键词: 声学, 驾驶室, 模态分析, 有限元法, 壁板贡献