# Tag Info

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Most thermometric cooling modules (Peltier devices) are made out of Bismuth Telluride which has a thermal conductivity of 1.20 W/(m·K), similar to ordinary glass. From this wiki list of thermal conductivities: Copper, 401 W/(m·K) Aluminum, 237 W/(m·K) So for a given temperature differential, a thermometric cooling module in the off state would conduct 334 ...

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TL;DR: The temperature in pot of water when food is placed in it is not only a matter of heat capacity. Other parameters like heat conductivity and convection have a significant effect on the transient temperature response. I will try to answer by taking a different simpler example, before tackling your example. Before I do that, I will point out that water ...

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At equilibrium, the heat entering the pot and the heat leaving the pot (heat flux levels) will be equal, otherwise the pot will either heat up or cool down. What matters here isn't the heat capacity of the contents, it's the heat flux leaving the pot. I'm assuming that the heat from the hot plate will be constant in both scenarios. It's not clear to me ...

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Air conditioning systems are a type of heat pump. Heat pumps are used to remove heat from a system at one temperature and transfer it to a system at a higher temperature. The heat pump lifts the energy from the lower temperature to the higher. In your case the outside ambient temperature appears to be always much lower than the required operating temperature ...

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One simple and effective way is to install an intake window with adjustable louvers near the lower part of your heat sink and a hood (can be possibly a primitive cardboard one) on top leading to the window/ vent on top. This way you create a self-sustaining circulation system that takes advantage of the rising tendency of the hot air coming off the heat ...

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You probably don't need any airconditioner. if the temperature outside remains a constant $20-25[^oC]$ then the heat transfer through the walls should cool the room down under $60[^oC]$. The only reason that might not be if you leave in a country with significant sunshine, and instead of having a good insulation at the roof you have something that heats up. ...

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The BTU British Thermal Unit is the confusing imperial unit of measuring energy. Heat transfer is in units of power or BTU/hr even though lots of professional heat transfer sources get lazy and just say "BTUs". It is an important distinction though when designing a system. 1 BTU/hr = 0.29 Watts of power. The heat loss in your building will be a ...

3

Could you get it to work, sure. There are dozens of ways to turn heat into energy. Could you get it to work at scale and cost effectively? Almost certainly not. There's just not enough energy in heated air to do much, and the capital costs of the system break the effort. This is another entry into the "Why can't Stirling engines give us almost free ...

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There are a lot of misconceptions in your question. Let's first start by the Carnot cycle. Given a two reservoirs at temperatures $T_H$ (hot reservoir) and $T_L$ (cold reservoir) where $T_H > T_L$, what is the upper limit of the mechanical work the can be generated if we added a heat engine between the two reservoirs? or in other words, what is the ...

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It is as fundamental as the proof you've given. The reason why $T_{in}$ has to be smaller than a $T_{out}$ is due to the second Law of thermodynamics. There exists for every thermodynamic system in equilibrium an extensive scalar property called the entropy, $S$ , such that in an infinitesimal reversible change of state of the system, $dS = dQ/T$ , where \$...

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