8 Replies Latest reply on Jan 27, 2015 1:51 AM by Jared Conway

    Function Curves; Harmonic Analysis

    Loris Volcizzi

      Hi everybody,

       

      My question is:

       

      I have the frequency spectrum of a pressure signal. Spectrum is composed by Frequency, Magnitude and Phase, but, if I want to put it into Solidworks (during the Harmonic Analysis), when I change the function curve of my signal, I've noticed the lack of the input "phase"; there is only the column of Frequency and of the Magnitude. So, how do I do to upload in SolidWorks my Frequency Spectrum?

       

      Thanks

        • Re: Function Curves; Harmonic Analysis
          Jared Conway

          could you show what curves you're trying to enter and a reference for the type of analysis you're trying to do?

           

          2015 SOLIDWORKS Help - Analysis Procedure - Harmonic

           

          2015 SOLIDWORKS Help - Harmonic Analysis

           

          Describe how the equations works and what is happening behind the scenes. Phase can be input when you input your curve but i'm not sure I understand exactly what your input is and how to use it.

           

          I'd also recommend checking the swx KB.

            • Re: Function Curves; Harmonic Analysis
              Loris Volcizzi

              Hi Jared.

              I can't show you the curve because it's trade secret (I'm a Master Thesis Student at Wärtsilä Italy). But I can say that I have pressure signal in the time domain; with this input I did "Modal Time History Analysis". Then, since I would like to know the frequency behavior of my model, I did with Matlab, the FFT and I obtained the spectrum of the signal for doing Harmonic Analisys. But, when I try to change function curves, I can't put it the phase of the spectrum, only magnitude and frequence, so I don't manage to do my simulation. Do you understand the problem now?

               

              Maybe, there is a possibility that I misheard the aim of this kind of analysis.

               

              Thank you

                • Re: Function Curves; Harmonic Analysis
                  Jared Conway

                  why can't you use the phase that i showed is accessible through the interface?

                    • Re: Function Curves; Harmonic Analysis
                      Loris Volcizzi

                      I manage to upload my "spectrum curve"..but the spectrum is the sum of many sinusoidal signals that have their phase. If I sum up every sinusoidal signals with their phases, I obtained original signal. If I put it without information of the phase, spectrum doesn't have the same meaning.

                      I red about Harmonic Analysis in the on line help of Solidworks, but it seems that there isn't this possibility for my case.

                      Or at least I don't understand what you say and your suggestion... I don't find the correlation between theory and the practise.

                       

                      Thanks

                      • Re: Function Curves; Harmonic Analysis
                        Loris Volcizzi

                        Maybe I found the solution; I should use Response Spectrum Analysis but in my current version of software or licence, I don't have this type of analysis in dynamic study.

                          • Re: Function Curves; Harmonic Analysis
                            Jared Conway

                            if you have sim prem to run harmonic, you can also run a response spectrum

                             

                            but that was added in sim 2012 or 2013 i think. so unless you're using a much older version, it may not be available?

                             

                            i'm actually still unsure what your input is. since you can't share yours, can you find an open source example that you can post?

                              • Re: Function Curves; Harmonic Analysis
                                Loris Volcizzi

                                I'm using Solidworks 2010; maybe in my version there isn't the possibility that you say; however a basic example of my problem is this:


                                Solid.jpg

                                I have signal in time domain (sorry for the mistake in the figure above; Signal, not Signale); then, with matlab and algorithm FFT, I did the Spectrum of my signal that you can see above, below the title "Frequency Spectrum". Signal in time domain is a sum of every sinusoidal signal that you can see in the figure with three axis, time, magnitude and frequency. When I go to solidworks property manager of Function Curve, I can insert only Frequency Spectrum in the figure above; but without information of the phase of every sinusoidal signal, it has no sense. Do you understand now?

                                  • Re: Function Curves; Harmonic Analysis
                                    Jared Conway

                                    nope sorry, do you have the information from a particular spec that you're trying to follow? maybe not the one you are using but another example?

                                     

                                    i'm also not sure if you're still looking to implement phase or something else at this point?

                                     

                                    this might be a good one to talk to your reseller about, maybe get on subscription to use the latest version that may address this and talk to them directly about it?