Recent content by james6008

Hi I have a damped simple harmonic motion model and I am altering the input force along with spring constant and damping constant. I can change the damping and spring constant to allow it to oscillate for few seconds before it stops at 0. What parameters do I need to change to alter the...

Hi I believe the formula you are talking about is: w = sqrt (k / m ) m = 5kg and I can re-arrange this to calculate the spring constant (k) for 2 Hz. I get a value of 790 which is way too high. In order to get a response of 1.5s I am using k=45. Another problem with the model is that if...

Hi I am trying to model SHM in Simulink as shown here: http://pundit.pratt.duke.edu/wiki/Simulink/Tutorials/DiffEq I have tried using different values of spring constant and damping to get instant response to the input force. I am measuring the displacement calculated by SHM. The force changes...

Thanks for the links :) The second article mentions "The typical form of such systems consists of a roller bearing connecting the tower and the nacelle, along with a tail fin mounted on the nacelle which aims to apply an apt torque to the nacelle so as to turn the turbine rotor to the...

Hi I have been looking for some simple equations that describe the turning moments on the rotor as wind direction changes. I know this can be relatively complex but I am looking for simplified equations. Has anyone got any information where I can find these? The wind turbine is a small...

But I thought gyroscopic forces depend on the rotational speed of the rotor and the angular velocity of yaw movement of the turbine. So in order to minimise the gyroscopic forces you apply brakes or design a system that slows down the rotor rotational speed during rapidly change in wind...

Hi From what I understand as the rotor yaws, there are gyroscopic forces that act upon it and the magnitude of these depends on the speed of yawing (e.g. 10 degrees per second). What happens to the rotor rotational speed during yawing? Does it slow down? Is the aim to slow down the rotor...

Perfect. Thanks for your help.

The initial angular velocity will always be zero because the object starts moving from equilibrium. So integrating angular acceleration gives me angular velocity. I thought integrating angular velocity will give me displacement/position or am I wrong thinking that?

Hi I am using Simple Harmonic Motion in a Matlab/Simulink model. Instead of using a motion for a simple pendulum, I decided to use a spring with a mass. The reasons for this is because my example is more like a lever attached to a pivot point and having an object at the end with a mass. A...

Hi I have calculated angular acceleration which changes with time. I also have a moment(torque) which also changes with time and a fixed moment of inertia. Is there an equation or a way for me to work out the change in angle with respect to time using this information? If not, what other...

Hi Thanks for this. I've had a look at this before but I got lost in the maths. I am already calculating the Moment which is Force*distance from the pivot The Moment of inertia is just mass m * square of its perpendicular distance r How will I link both the first equation and second one...

Hi I am trying to create a model to simulate the motion of a weather vane. It basically looks at the wind direction and as the wind direction changes, the objects responds by trying to align itself parallel to the wind. First of all I am looking at the force perpendicular to the pivot...

Hi everyone I just need some help with this question. Its a simple one I'm pretty sure. Homework Statement A solid sphere of radius 3 cm is made from a conductor and has a charge of + 4 uC placed upon it. What is the electric field strength 1 mm from the centre of the sphere? Homework...