heat load to warm up a truck
heat load to warm up a truck
(OP)
Hi,
I'm trying to find the heat load to warm up a 70 tons truck within 8 hours, from -40 deg C to 15 deg C. I found 246 kW*h. Is that ok?
How the heat should be distribute on the truck?
Any ideas?
Thanks!
I'm trying to find the heat load to warm up a 70 tons truck within 8 hours, from -40 deg C to 15 deg C. I found 246 kW*h. Is that ok?
How the heat should be distribute on the truck?
Any ideas?
Thanks!





RE: heat load to warm up a truck
Second even if you know the rate at which you need to apply the energy it still does not mean it will heat up that fast since you have to use heat transfer equations to see if the heat will be absorbed by the truck at this rate.
The simplest way to calculate the total quantity of energy is to use the equation Q=mCp deltaT where Q is the total amount of energy, m is the mass, Cp is the heat capacity of the material (I would assume most of the mass is steel in your truck), and delta T for your case is 15 - -40 = 55 deg. C.
The heat transfer equation(s) will be in the form Q=UA deltaT where U is the overall heat transfer coefficient and A is the surface area. It will actually be a very complicated equation given the shape and thickness of the truck.
Distribute the heat over all the surfaces. I would assume this is some type of large truck in the artic. Probably a combination of radiation (infrared) and convection (forced hot air) would be the best.
RE: heat load to warm up a truck
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RE: heat load to warm up a truck
Please show me where I'm wrong in my caculations
RE: heat load to warm up a truck
But your delta T of 131ºF is 72.8ºC, which is 30% higher than the stated delta T of 55ºC.
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RE: heat load to warm up a truck
RE: heat load to warm up a truck
then 17080 btu x 99*F = 1690920 btu/8hrs = 211369btu/3412 = ~62kwh Thanks IRstuff
RE: heat load to warm up a truck
RE: heat load to warm up a truck
The calculated heat flow requires an infinitely conductive object. If there's a lot of thermal resistance, then you'd need a substantially higher heat flow to make up for the thermal resistance.
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RE: heat load to warm up a truck
RE: heat load to warm up a truck
Now that's funny!!! Thanks for that Cris
RE: heat load to warm up a truck
I think that some electric heaters blowing hot air on the truck will be appropriate. But what is the kw and cfm needed?
RE: heat load to warm up a truck
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