Ship and ocean platform structure broadband line spectrum vibration noise time-frequency integration forecasting method

Abstract

The invention belongs to the noise forecasting filed and especially relates to a ship and ocean platform structure broadband line spectrum vibration noise time-frequency integration forecasting method. The method is characterized by acquiring the time domain or frequency domain loads of a ship and ocean platform equipment; then, establishing a ship and ocean platform structure vibration noise analysis finite element model, and taking the time domain vibration signal a of the ship and the ocean platform equipment as input, reasonably controlling a time increment step deltat and model calculation time Tt, carrying out ship and ocean platform structure vibration noise simulation calculation, acquiring ship and ocean platform structure broadband response x(t), and carrying out FFT conversion on steady-state response to obtain ship and ocean platform structure frequency domain response; and based on the above condition, carrying out the dominant transmission path analysis of the ship and the ocean platform for a frequency point with large vibration response and the frequency point which needs to be focused on, and realizing the rapid quantitative analysis of a ship and ocean platform broadband line spectrum vibration noise. By using the method, a line spectrum capture capability is good, solving efficiency and forecasting precision are high and an application prospect is wide.

Description

Technical field [0001] The invention belongs to the field of noise forecasting, and specifically relates to a time-frequency comprehensive forecasting method for broadband line spectrum vibration and noise of ships and ocean platform structures. Background technique [0002] The existing broadband line-spectrum vibration and noise prediction processes of ship and offshore platform structures are mostly based on wave theory or modal superposition theory to analyze in the time domain and frequency domain respectively. This type of method has the advantages of intuitive analysis. However, the current application of this method to the prediction of the vibration and noise of ships and offshore platforms still has the following shortcomings: [0003] 1. Existing ship and offshore platform structure vibration and noise prediction are mainly based on wave theory or modal superposition theory to analyze in the time domain and frequency domain respectively; in the time domain analysis proce...

AI Technical Summary

Problems solved by technology

[0003] 1. The structural vibration and noise prediction of existing ships and offshore platforms is mainly analyzed in the time domain and frequency domain based on wave theory or modal superposition theory; Quantitative analysis of the dominant transfer path cannot be carried out; in the frequency domain analysis process, the influence of many nonlinear factors is ignored, and there are disadvantages such as large calculation scale, low solution efficiency, and narrow calculation frequency band, and may be lost due to improper selection of calculation steps. This leads to the omission of the resonance peak, and the so-called "peak leakage" phenomenon occurs, which leads to large errors in the calculation results.

[0004] 2. For the structural vibration and noise prediction of ships and offshore platforms, there is currently no effective method that combines the accuracy and efficiency of dynamic noise prediction and can analyze the dominant transmission path of vibration and noise

Images