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 saisanthoshm88 June 1, 2011 11:49

Transient heat flow

I'm totally new to transient simulations. I had a newbie question. I was simulating the air flow inside a power amplifier cabinet which had Fans, Power sources and power amplifiers inside.

The power emanation from the amplifiers is of a transient nature and is described by the following details:

Output Power = 200 W

Duty cycle: Transient attribute:Gaussian, Total pulse duration: 6400 ms

So I see that I need to consider 6400 ms as the total time with a time step of 400 ms. But this is something relevant to a single duty cycle so will it be fine to analyze the heat flow inside the cabinet just for a single duty cycle on these lines.

Can some one please suggest me regarding this.

 ghorrocks June 1, 2011 18:29

In most electronics heat modelling things of this time scale can be averaged out and the avergae heat load used. So I would average the heat load out and apply a constant heat load. But if you are doing a transient simulation anyway then it is easy to apply the transient heat load.

 saisanthoshm88 June 7, 2011 12:02

Glenn could you please tell me how to calculate this average heat load. I apologize for raising such novice question but my experience is really too limited in this.

 ghorrocks June 7, 2011 19:00

Integrate the heat load over a long time. If it is 11W for 1s and then 1W for 4s, and then repeats that pattern forever, then integrating over the full 5s cycle gives (11*1+1*4)/5 = 3W average load.

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