Technology Numerical Simulation
Acoustic Analysys
Aerodynamic Noise Radiation from High-speed Train's Surface
The aerodynamic noise radiated from a high-speed train causes an environmental problem. As a train speed increases, the aerodynamic noise increases drastically, so the reduction of the aerodynamic noise is very important.
We calculate the aerodynamic noise radiation from a vestibule side door. The side door is installed at the recessed position from the train surface, and the unevenness can be an aerodynamic noise source.
First, we make a flow analysis around the door. The figure shows the average deviation of pressure by the gradation from blue to red. This pressure fluctuation is the noise source.
Next, we calculate the aerodynamic noise radiation from the pressure fluctuation of the flow analysis results. The figure shows the sound pressure level distribution (left) and the propagation of the noise (right) at a certain frequency. We find the noise is mainly radiated from around the following corner.
Noise Analysis of Antenna Shroud
Aerodynamic Noise from Antenna on Shinkansen
When Shinkansen runs at high speed, objects stuck out from the train surface make aerodynamic noise. It is important to understand from where the aerodynamic noise is radiated in order to reduce it. We search aerodynamic noise source of an antenna shroud on the top of Shinkansen with fluid analysis. Pressure fluctuates most at red part, which is the main noise source.
Prediction of Vibration and Sound Pressure Level with Statistical Energy Analysis
in the tunnel
We simulate the passenger room noise when a train is running in the tunnel with SEA(Statisical Energy Analysis). SEA is a method to enable us to predict the passenger room noise level of train car at a low cost. We made sure of the accuracy of the passenger room noise prediction with SEA, by comparing the caluculated results with the experimental results.
Numerical Simulation
Structual AnalysysFluid AnalysysAcoustic AnalysysTesting＆Phototyping
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