Recent content by rsk2mc

It is not depresserized. It is a form of shielding. The reason I posted this is because my initial calcs are off by 80 degrees and I'm not sure what I'm missing. I am on the process of running an Ansys analysis but I was hoping to solve this by hand. We have tested this which is how I know the...

No, the pcb is set inside the copper enclosure. The heat is mainly caused by rf and stray currents.

No, it's all enclosed.

There is air space between the pcb and the inner copper box.

The material is ULTEM and the pcb is FR4.

This design was actually made by Electrical Engineers, then the obvious problems occurred, MEs were brought in.

The above info is what was given to me, I did not derive these numbers. I have been away from heat transfer for quite a while, I'm more focused in stress analysis. This is in a controlled environment, this is a healthcare application.

Hello, I will try and provide as much detail to the problem as I can with the hope someone can help me solve this. We are currently working on a wireless project that contains high electrical currents, because of this the box the electronics are enclosed in experience quite a temperature rise...

Also your rpm changes. The circumference (pi*D) is less on the smaller diameter.

The best way I understand it is to think of a torque. Torque is a force applied over a distance that causes twisting. When you think of moment think of torque, they essentially are the same thing.

you have to convert velocity to angular velocity to when you are using a spinning shaft. Angular velocity is calculated by v = r × ω Where: v: Linear velocity, in m/s r: Radius, in meter ω: Angular velocity, in rad/s To do this in RPM you would use v = r × RPM × 0.10472 Where: v: Linear...

Take a look at this link http://www.engineersedge.com/fluid_flow/pressure_drop/pressure_drop.htm

Since velocity is a linear measure (distance of time) and you are spinning a shaft which is angular velocity you have to relate them by converting velocity to RPM. Hope this helps!

I would double check this but in English units HP= torque * rpm ÷5252. So if you calculate the required torque, you know the HP of the motor you find rpm. So translate you required speed to rpm and I think you got it.

To calculate the torque required its simply 1/2*D*L where D is the pulley diameter and L is the load.