Recent content by Fluidman117

  1. F

    Choosing a generator for a wave energy demonstrator

    Hey! I am building a small scale wave energy converter for testing in a wave tank. I have my device almost ready, but I am still missing a generator. My idea is to just to show that my design works and I can light a light bulb. I can convert my linear motion to rotary motion. Then I can use...
  2. F

    Adjustable Gas Spring - Find an Automated Solution

    Hey, Has anyone heard of a gas spring that could be adjusted in mid operation? The gas could be released from the gas spring to decrease the pressure inside and alternatively gas could be injected by a compressor to increase the pressure in gas spring. I have only found gas springs, in...
  3. F

    Peak frequency of a signal depending on the length of the signal

    @Baluncore Before I didn't use any window function at all, but later tried the Hanning window, which reduced the peak at higher frequencies. This gave me slightly improved results. But thanks for the insight! @sophiecentaur I have an amplitude spectrum, in which y-axis is the amplitude and...
  4. F

    Peak frequency of a signal depending on the length of the signal

    Okay, this makes sense. Because at every time instant I sum all the frequency components and the peak frequency is always the same. And thus when taking the FFT for a certain length of the signal, the peak frequency should be the same. This is what I am experiencing, the shorter the sample the...
  5. F

    Peak frequency of a signal depending on the length of the signal

    You almost understand me - what I meant is that I have frequency components, each with different amplitude. The highest amplitude is for 0.2Hz. Then I sum these components to generate the signal in the time domain.
  6. F

    Peak frequency of a signal depending on the length of the signal

    Hello everyone! I am generating a signal as a function of time. This is an irregular signal generated by using the superposition principle and random phase. Thus I actually have already all the frequency components of the signal. And from the frequency components I know that there is also a...
  7. F

    Should Integration by Parts Be Used on Functions Like \( x \cdot y(x) \)?

    Okay, then I believe I was mistaken. It seems that I also need to apply the reverse power rule to ##y(x)##. So an example: ##y(x)=2*x## A=\int^{2}_{1} x*y(x)*dx=\int^{2}_{1} x*2*x*dx A=\left|2\frac{x^{3}}{3}\right|^{2}_{1}=4.6667 Is this correct? I also looked up the integration by...
  8. F

    Should Integration by Parts Be Used on Functions Like \( x \cdot y(x) \)?

    Homework Statement I want to take an antiderivative of a function with respect to x. But in addition the function includes a term y (x) that is a function of x itself. Do I have to apply the reverse power rule also to y(x) also? The integral can be seen as an indefinite. Homework...
  9. F

    2nd Order Differential Equation with Improved Euler Method (Heun's)

    Homework Statement I would like to solve a 2nd Order Differential Equation using the Improved Euler Method. The 2nd ODE is a Mass-Spring-Damper equation. I tried coming up with an solution for the Improved Euler Method, but not entirely sure. Can you help me and have a look if this is correct...
  10. F

    Solving Equation w/ L'Hopital's Rule When x = 0

    But if I would still like to use L'Hopital's rule, how should I proceed?
  11. F

    Solving Equation w/ L'Hopital's Rule When x = 0

    Homework Statement I have an equation in which a term equals zero and in this case the whole equations equals zero. I know it is possible to use the L'Hopital's rule to calculate the equation but having I'm having a little trouble. Homework Equations The equation I would like to is the...
  12. F

    How to Determine Mass Flow Rate for Adiabatic Compression of Nitrogen?

    Homework Statement Nitrogen was compressed from initial pressure of 101 kPa to a higher pressure. The respective enthalpies are: 54 kJ/kg and 350 kJ/kg. The compression process is adiabatic and ideal. The volume flow rate is 0.05 m^3/s. Density of Nitrogen before entering the compressor is...
  13. F

    Calculating Damping Coefficient of a Generator

    You are right about the squirrel cage. However, I found this: http://www.uwig.org:8080/index.php?title=Wound-Rotor_Induction_Generator_with_External_Resistance_Control And seems that when opting for the wound rotor it is possible to modify the resistance by external circuit. And here...
  14. F

    Calculating Damping Coefficient of a Generator

    Thanks for the reply. Then I could say that the damping coefficient is just the rotor resistance. Thus it would also be possible to modify this resistance by adding an external resistor circuit to the main circuit and modifying the external resistance I could modify the damping coefficient. I...
  15. F

    Calculating Damping Coefficient of a Generator

    Hey, I understand that damper windings are used to stabilize the speed of the rotor under varying loads. The rotor speed is decreased or increased by the induction principle. Physically the damped windings are some sort of copper bars inserted into the pole faces of a rotor and all...
Back
Top