# Help Me Find An Environmental Housing

Hi My client is given me Heat Readiation, we need to find sutiable camera enclosuer can helps me

The heat radiation loads to design for are as follows: 15 minutes at 3000 Btu/hr-ft2 [9480 w/m2] 8 hours at 1200 Btu/hr-ft2 [3792 w/m2]

Regards,

I think the trick here is to convert your values into usable terms. BTU/hr per square foot/meter is not going to help find you the right housing.

Most environmental housings are specified by operating range. Take this example from Moog (Thermiq):

They do figure EPA, but it is not expressed in terms of heat transfer. Instead, you are left with an "Operating Temperature" of -50F up to 140F, with 'spikes' up to 165F.

Granted that is a rather imprecise value and range, but that's the metric used by housing manufacturers. No RH or entropy is part of that figure. :)

So, with that out of the way - can you restate the application as a min/max operating tempature value?

What does that mean in terms of the temperature range inside the box?

For example if the outside ambient temperature is 140F continuously, what's the inside temperature?

The problem is that we are not talking about ambient heat. We are talking about radiated heat, like the sun or a flame or a heat lamp.

For example the enclosure that you show is speaking about a ambient temperature of 140F. That means the air temperature around it is 140F. But what if the Sun is directly shining on it overhead? Does it matter? Sure does.

Direct Sunlight irradiates 97 W power per square foot. How much of a temperature rise that will cause depends on the size, shape and heat dissipation of the enclosure itself. So the OP is correct in specifying the radiated energy that must be dissipated. Note the the radiation values given in the OP are orders of magnitude higher than Sunlight. So high in fact that the ambient temperature may not even be a significant factor.

Think microwave oven, does it make much of a difference how hot the air is inside the oven to how fast your food heats up?

An active cooling system possibly including freon/puron is likely necessary.

@Sripad, to spec the enclosure it would be helpful to know the camera dimensions and if there are any restrictions on the size or shape of the enclosure.

This concludes today's thermodynamics lecture... *eyeroll*

The point is you're not going to find a camera housing using reflected heat loads.

I also challenge your recommendation that an active cooling system is necessary. There are air-cooled furnace cameras rated for thousands of degrees that don't need refrigerants.

Bottom line: There's a bunch we don't know about this application, like the ambient temperature range. Let's start there and work our way up.

This concludes today's thermodynamics lecture... *eyeroll*

I hope 'entropy' is not on the test... :)

ther is no restriction in size, we just want to know the operating temp to use these

Have you chosen a camera to use yet?

If yes, what model?

If no, are you asking for help in choosing both the camera and an enclosure?

If you need help with the camera, you need to tell us more about what it is being used for.

Can you confirm the radiation is infra-red?

And that the camera is to be operating in the visible light spectrum?

(sounds like it will need one heck of an IR cut filter... :)