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基于FPGA与DSP遥测声压谱分析装置设计
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作者 张凡 王丽蓉 +1 位作者 孔凡玲 施睿 《电子器件》 CAS 北大核心 2023年第2期449-454,共6页
为压缩飞行器遥测系统运行过程中的数据传输量,设计了遥测声压谱分析装置。设计基于FPGA与DSP双核架构,配合流水线作业的设计理念,采集信号的同时进行数据时频转换,并实时将数据处理结果传输给外部设备。噪声信号声压谱密度(SPL)算法运... 为压缩飞行器遥测系统运行过程中的数据传输量,设计了遥测声压谱分析装置。设计基于FPGA与DSP双核架构,配合流水线作业的设计理念,采集信号的同时进行数据时频转换,并实时将数据处理结果传输给外部设备。噪声信号声压谱密度(SPL)算法运用1/3倍频程的方式选择噪声的频率带,采用快速傅里叶变换法(FFT),极大地降低运算量,缩短数据转换时间,从而实现数据传输的实时性。测试结果表明,该数据预处理装置算法的误差小于3.4%,设计具有良好的实时性和稳定性,具有较高的实用价值。 展开更多
关键词 数据处理 遥测声压谱分析装置 声压谱密度(spl) 1/3倍频程 快速傅里叶变换法(FFT)
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Experimental investigation of typical surface treatment effect on velocity fluctuations in turbulent flow around an airfoil
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作者 Babak ELHAMI Mojtaba DEHGHAN MANSHADI Ali Akbar DEHGHAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第10期112-123,共12页
Noise reduction of different airfoils is important because these sections are used in wind turbines,propellers,and aircraft wings.Several methods are used for passive noise reduction of sections.One of these methods i... Noise reduction of different airfoils is important because these sections are used in wind turbines,propellers,and aircraft wings.Several methods are used for passive noise reduction of sections.One of these methods is the use of surface treatment.In this research,the effect of the typical surface treatment element(finlets)on the vortex structure at different frequencies in the turbulent flow created on the NACA2412 section is investigated.For this purpose,one-dimensional hot wire probe is used.The used surface treatment in this research has a special geometry and the distance between two consecutive finlets is 6 mm(S=6 mm).This study shows that this surface treatment element can be used for noise reduction in high frequencies.Another result of this research is the suggestion of the most suitable position to install this special surface treatment element to reduce vortex energy in all frequency ranges.This installation location is determined based on a dimensionless parameter(X_(aft)/h). 展开更多
关键词 Finlet spacing Passive noise reduction Sound pressure Level(spl) Surface treatment(finlets) Velocity power spectral density
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