Calculation of the heating time of the moulds

Simulation Generality
1

Hello 

Here is a question that may be obvious but not for me, I want to calculate the heating time of any mold in the oven knowing that the number of molds as well as the shape and weight of each one is random, we have 2200 molds, of four different frames, we cannot predict the number of molds to be heated at the same time, It all depends on the production load.

I have to find a formula, maybe an approximation that we only know the weight of a mold allows us to determine the heating time independently of the other molds

You will find attached a real photo of the oven and a diagram, the molds can be put horizontally or vertically, already if you are better to put them horizontally or verically

Last question is there a software to make a simulation of the air flow in the oven, i.e. to determine the hottest zones, in air velocity depending on the location.

Thanks in advance

2

Hello to you.

The fact is that the volume of your molds is random, so you can't find (except after 15 years of research and it will still be uncertain) a formula for it.
Only experience takes precedence over that! Even if you find a formula, it will remain theoretical because no parameter is fixed (size of your molds, location of your molds...).

But that's my opinion...

Call mould makers, they will guide you
 

PM

1 Like
3

Hello

The more volumes you have to heat, the more calories you will need, so either more time or more power.

If the number of molds is quite random, it is very difficult to determine a formula even with load assumptions.

If the objective is to know the heating time of a ceratin molded at a certain location, why not affix temperature probes or thermal cameras to it? We use these systems to track our vacuum brazing times.

2 Likes
4

question 

  1. Is your oven a tunnel?
  2. a closed box with only 1 door?

via your cutting diagram I find inconsistencies in operation to optimize the rise and maintenance of temperature to have a homogeneous temperature

for me the airflows are not optimized

  • where the  resistance upstream of the fresh air is not done
  • stale air extraction after the ventillo even less

What do you know

  • your fan has a flow rate depending on the pressure drops
  • your resistance(s) have a power
  • your inlet room temperature
  • your room temperature
  • your desired temperature of your mussels
  • you don't know the mass of your mussels 

so you have an oven that has such power

so according to the weight of the mussels as an input

Your heating time will be proportional to the mass of your molds

That's it for a first draft

Waiting for answers

@+ ;-))

1 Like
5

Hello 

I think it's because of the convective transfer coefficient that I couldn't determine the heating time of the molds.

As the speed of hot air is not the same at the inlet as in the middle of the oven and at the outlet, so I won't have the same coeffcient.

For some molds I found values very close by theoretical calculation than by experience