Recent content by steeno

Hi Dave, Greg and all I am still working on my wind turbine project. Its been divided a bit in focus: 1) Wavelet analysis, therory and background This part of the project focuses on getting *fast* vibration measurements with a short observation time. But its true that wavelets are not the...

Thanks from the swantec.com homepage: ...marketer of sophisticated ultrasonic diagnostic systems that accurately evaluate the operating health of industrial machinery. SWANTECH's proprietary, patented and field-tested Stress Wave ANalysis (SWAN™) technology is revolutionizing the global...

Thanks for an interesting thread ! To ElectricPete (glow, glow) Yes - the way to do it is Root Mean Square -RMS. There was an interesting thread pointing out that Parsevals Relation shows that RMS in time and frequency must end up with the same result. Its a truly wonderful feeling to see...

Thanks Greg From now on I shall use the term blade passing frequency (BPF). I was thinking about the wind measurement after writing my last posting yesterday. I was reaching the conclusion that the wind changes must be abrupt (like a square wave) in order to produce a series of harmonics...

Thanks Greg I shall read carefully what you have written about waterfall plots / 3D plots. The sentence about the wind speed was my own. Here is my background for trying the correlation idea: I have a readout here of wind speed versus time recorded at 32 samples/s. The wind speed lies in...

Sorry - waterfalls and order plots ? Maybe a book reference would help me here. Also I could use a few more words about the idea of relating the sampling freq to the rotation freq of the main shaft of the wind turbine. On my desk lies Steven W. Smith:"The scientist and Engineer's...

Ok. A 30 years old non-profit org with interest groups all over USA. I must try and find someone there with insight in wind turbines. The Stevens homepage has been recommended at other threads. I quite like its approach. Everything is explained in very basic terms. Just what I need. I emailed...

Ok Greg thanks. I have asked the univ. lib. to search these standards. I suspect you are a gear box specialist and that your references are related to the gear box part of my question (smart eng-tips feature...) The cpy I work for have been presented for FAG experts presentation on gears and...

Hello Mech/Acou/vib people I am defining a project in Digital Signal Processing. My theme is vibration in Wind turbines. I am looking to all sides for - books - articles - web sites All inputs are of interest. My level: I have the following mechanical items: Fundament with tower. Mill hat...

How about this: (I know nothing about earth quakes, we only have tiny tiny ones and they are by the way mostly reported nightly - needs silence to be recognized here in Danmark, Europe so this is just guessing) Lets assume that the earth quake begins with a huge mass being moved abrubtly -...

Now I have read this thread a couple of times. I have an interesting task of measuring vibration peaks generated by a wind mill. So for me it will be of main interest to evaluate peaks in a freq spectrum and say something about the height of the peaks. I just want to mention Steven W Smith...

I have a passion for signal analysis and flute playing. My flute maker intends to market some new tubes and I want to measure their vibration qualities. I could mount a head joint on one of these tubes and produce a sound. This sound could be recorded and I could do an acoustic analysis. But...

This is a reply to rollercoaster-Rich2001 as my request is boy-ish too: I have an interest in acoustics and flute playing. My flutemaker has come up with some new tubes. He claims that they will produce a better sound than conventional tubes. I would like to help him prove this. But how ? I...

This is a reply to rollercoaster-Rich2001 as my request is boy-ish too: I have an interest in acoustics and flute playing. My flutemaker has come up with some new tubes. He claims that they will produce a better sound than conventional tubes. I would like to help him prove this. But how ? I...