copper coil around a shaft 1

[nekojita]

Hi,

I want to model the transient heat transfer characteristics of:

a zero pitch coil (30 gauge polyimide copper wire, 10 mm long) wound on a hollow cylinder (nylon tube 2.5mm OD, 0.5mm ID). The coil has a very thin layer of polyolefin over it. (.05mm). Two additional layers will contact the polyolefin acting as the q out for the coil, the first, 0.5mm thick, the second, 2.0mm.

In this model, the coil will be set for constant temperature.

I have the the following questions:

1) How to create the model of the round wire on the shaft material? (3D)

2) How to create scenarios where the thin layer of polyolefin is conformal to the coil and also where there are air gaps because the polyolefin does not conform to the shape of the coil.

3) How to create the layer in contact with the polyolefin that is uniform,i.e., entire area has same q out? The q out is not constant with areas of higher and lower q out?

Thanks,

Art

 

[nekojita]

I am back to using the spring macro and cannot figure out how to create a spring with zero pitch. As I move the coil spacing closer, I reach a point where the macro bombs though the pitch is still not zero. The inputs to the macro are:

OUTER DIAMETER OF SPRING --> 3
DIAMETER OF SPRING WIRE --> 0.127
NUMBER OF ACTIVE COILS --> 40
FREE LENGTH OF SPRING --> 50
KEYPOINT ANGULAR DISTANCE -> 5

The coil pitch is FREE LENGTH OF SPRING/NUMBER OF ACTIVE COILS= 1.25 mm which isn't even close to the wire diameter. Also, what does KEYPOINT ANGULAR DISTANCE specify?

Thanks,

Art