Still low airgap flux density-help please

Altair Forum User

Problem solved. 

 

Altair Forum User

forget to add, to run the program, first click mesh domain and then run the test scenario.

Altair Forum User

an attempt to move up the queue.

asoualmi

Hi,

Currently I am  analyzing your project. I will keep you informed.

 

Best regards.

Altair Forum User

thank you, i will turn my notification on for this thread.

asoualmi

Hi,

Sorry for the delay, time to analyze the Flux project. To be sur that what we get in Flux is correct, I used Ampere theorem.

In your case, the formula that I used to compute the flux density in the air gap is:

B=(Mu_0*N*i)/e. where:

N: number of turns in the rotor

I: current in the rotor (300 A)

E: air gap thickness

B=(4*pi() e-7*2400)/11 e-3 = 0.27 T.

I found the same thing as in Flux when I draw a path in the air gap.

As a conclusion, the value of the flux density in the air gap is correct.

Hope this help.

Best regards.

Altair Forum User

Altair Forum User said:

Hi,

Sorry for the delay, time to analyze the Flux project. To be sur that what we get in Flux is correct, I used Ampere theorem.

In your case, the formula that I used to compute the flux density in the air gap is:

B=(Mu_0*N*i)/e. where:

N: number of turns in the rotor

I: current in the rotor (300 A)

E: air gap thickness

B=(4*pi() e-7*2400)/11 e-3 = 0.27 T.

I found the same thing as in Flux when I draw a path in the air gap.

As a conclusion, the value of the flux density in the air gap is correct.

Hope this help.

Best regards.

thank you for your explanation. If I use your formula, the number of turns is actually 32.5 turns in the rotor. So, B=(4*pi() e-7*32.5*300)/11 e-3=1.1T. Can you please explain why you used 2400(8 turns?)? many thanks in advance. I have stuck on this for a while and this is the first time i encountered this problem since upgraded from Flux 11.1

Altair Forum User

trying to bump up the queue again.

asoualmi

Hi,

The path chosen to apply the Ampere theorem is on one rotor tooth. For this reason I divide the number of turns by 4. In the end the total is (32.5/4)*300=2400.

 

Best regards.

Altair Forum User

Altair Forum User said:

Hi,

The path chosen to apply the Ampere theorem is on one rotor tooth. For this reason I divide the number of turns by 4. In the end the total is (32.5/4)*300=2400.

 

Best regards.

thank you for your help. the problem has been solved. the flux density is now 0.9 in the airgap as per my original assumption.