Questions tagged [thermal-conduction]
The thermal-conduction tag has no usage guidance.
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Which method of heat transfer is faster? Convection or Conduction? [closed]
True or false question!
Conduction is the slowest mode of heat transfer - true (given in internet)
Now my question is, let's say you want to boil some water, in this case should not be the conduction ...
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Using Thermal Conductivity measurements to estimate the thickness of a LI-900 Silica tile required to lower temperatures by 1450K
I'm diving into Fourier's Law at an IB Physics level, where we use the equation ΔQ/Δt = k * A * ΔT/Δx.
This equation is directly from the IB Databooklet, and as it's the first time it's been included ...
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Effect of having infrared reflective paint on a room with and without a heat source
I am trying to check if my understanding is correct. This is not really a question but a request for validation. I hope this is allowed.
When painting with a heat reflective paint there are two ...
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Is stoßlüften - quick exchange of air through windows actually more efficient than slow exchange through a wall ventilation fan?
In German areas with near air-tight homes, it is recommended that full house ventilation is performed by stoßlüften - opening windows fully to exchange as much air as possible in shortest amount of ...
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Can a tea light really heat a greenhouse?
It is a common suggestion amongst greenhouse enthusiasts that a long-burning tea light inside an upturned terracotta pot can be enough to keep frost away from plants. Is this possible?
Instinctively, ...
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How does white powder coat change aluminum emissivity?
I have a telescope with an aluminum tube powder coated white. I took 940 temperature data points from a temp sensor attached to the tube and a weather station for ambient temperature.
It seems the ...
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How does wetting cotton increase its UV transparency?
Anecdotally, a dry cotton T-shirt prevents sunburn better than a wet one.
This has also been measured (Gambichler et al., "Influence of wetness on the ultraviolet protection factor (UPF) of ...
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Temperature Estimation for Insulated Bottom Surface in Water Cooling
In a 2D plane heat flux q'' is incident on an insulation layer (which has a thickness L and a thermal conductivity k). The bottom surface of this insulation layer is exposed to water cooling with a ...
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Thermodynamics: A piston can freely move inside a horizontal cylinder which is closed from both ends
Is it safe to say that regardless of where the piston is, the final pressure on each side of it would remain the same. And if yes, then why?
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Rate of Thermal Conduction between different materials
I'm aiming to use differential equations to simulate thermal transfer between different materials in a 3D space, however, my physics knowledge is lacking. Is there a formula that can give the rate of ...
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How does a counterflow heat exchanger achieve efficiency of 0.5 and greater?
Basic thermodynamics says that for thermal energy to flow from one place to another there must be a difference in temperatures.
For example typical heat recovery units use hot air (25 °C) to heat cold ...
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At temperature $T>0K$, are all normal vibrational modes present simultaneously in a one-dimensional solid?
I am studying Debye theory of Specific heat.
hyperphysics has this picture and there it says
"Considering a solid to be a periodic array of mass points, there are constraints on both the minimum ...
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Is it possible for an absorption refrigerator to pump heat to a reservoir that is at a higher temperature than the heat source used to run it?
Judging by the wiki page I get the feeling that this type of heat pump would not function if it's radiator were hotter than the heat source, but I can't quite put into words why and I feel like there ...
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Why do we move the spoon in a plate to cool it down?
Say we have a plate full of soup, why to cool it down we move the spoon around in the plate? Is it to facilitate the thermal interchange between the air and the soup? Also why is the edge of the plate ...
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Why is a inviscid flow assumed to involve no thermal conduction and mass diffusion? [closed]
I can understand how the assumption of inviscid flow leads to Reynolds Number (Re) tending to infinity. But how does the assumption of inviscid flow lead to the assumption of no thermal conduction and ...
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Does radiant barrier work if hidden under timber structure
I am insulating my house roof and I wanted to explore the radiant barrier and if these are actually effective in a real life scenario.
The desired outcome of installing such barrier, would be to ...
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Why haven't we found thermal superconductors?
First of all I want to apologize if this is a stupid question. I'm a layman who's merely very interested in physics, without a degree to my name.
I was trying to research electric superconductors ...
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Why does a baking tray sometimes warp in the oven, but a frying pan never does on the stove?
I can take a thick case iron frying pan and heat it on the stove until oil smokes. I do this regularly to season it. The heat is high. Temperature gradients are high. But the frying pan never warps.
...
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Time for a room to be heated with various heat sinks and sources
I have a question where I have to calculate the time for a room to reach a certain temp. The room is heated using a heater and there are internal fixtures which absorb heat, aswell as heat loss to the ...
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Is Newtons Law of cooling applicable for all forms of heat loss? [duplicate]
Can heat loss through Conduction, Convection and Radiation be explained by Newton's law of cooling?
Or it is just applicable for heat loss through Convection and Radiation?
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Heat being transferred from colder object to hotter object
My son was watching a YouTube video on entropy (The Most Misunderstood Concept in Physics). At about 11:30, it said that in theory it is possible to observe, say, "heat" moving from colder ...
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Some questions about heat flow in this example
I'm new at heat transfer and I have three elementary questions from the book "Fundamentals of heat transfer" by Incropera et al. This is Example 1.1 in the book:
(1) What is the definition ...
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Temperature profile of a table with a hot tea mug on it?
When you place a hot mug of tea or coffee on a cool table, heat transfer causes the table surface's temperature (and what lies beneath that surface) to increase.
My question is: what's the temperature ...
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How could we caluculate the amount of heat transferred through convection when a fluid flows over a curved surface?
In the case of convection heat transfer during fluid flow over a flat plate , we deduce the governing equations based on conservation of mass , momentum and energy, using this equations we find the ...
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Why is rock or metal often cold to the touch but wood or plastic is not?
In a room at normal room temperature, certain materials, such as metal, glass, ceramic, or rock, will feel cold to the touch, but others, such as wood or plastic, do not so much.
Which physical ...
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Heat equation and discontinuous thermal conductivity in the finite volume method
I am looking for a rigorous way to deal with discontinuous thermal conductivity $K(x)$ in the heat equation (e.g. on the boundary of two different materials)
$$ u' = \nabla_x\cdot (K(x)\nabla_x u) + \...
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Heat flux in the negative radial direction in a hollow cylinder
Imagine a non-insulated pipe transporting steam at say 100°C. If outside the pipe, the bulk temperature is, again, say 25°C.
Then, due the temperature gradient a heat flux will be established across ...
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Physics in the kitchen: does heat transfer faster from air into oil or from air to food when in an oven?
It is usually said that foods cook faster in an oven when coated in oil. While I can understand that the underside of the food will cook faster where the oil forms an thermal interface between the ...
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Why is the specific heat of conductors and insulators not same at high $T$?
This is about contribution of electronic specific heat to metals. Most of the books ( I have checked Mermin) have done electronic specific heat calculations at low temperatures using sommerfield ...
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Simulating Dirichlet Boundary Conditions for Lattice Boltzmann Method
So, I'm going through A.A. Mohammad's book "Lattice Boltzmann Method : Fundamentals and Engineering Applications with Computer Codes." And I'm currently coding the D2Q9 lattice with respect ...
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Solving heat equation with fixed temperature at $x=0$ [closed]
Suppose, there is an insulated 1d rod of length $L$ with initial temperature of $T_{0}$. Suddenly, the beginning of the rod is heated such that its temperature is fixed at $T_{f}$, while the other end ...
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On the non-quasistatic transfer of heat
Suppose we have two bodies at different temperatures, and we let them interact thermally in such a way that the process is not quasistatic (e.g. two different metal spheres touching). Do we arrive at ...
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Heat Transfer between 2 bodies
What are we supposed to do when two bodies are in contact to solve heat transfer over time?
Consider this one dimensional problem:
Suppose I have Body $A$ in perfect contact with Body $B$ via a ...
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Cup of warm water suspended in a pot of water held at a steady boil
The question asked by a website is as such (possibly behind a paywall):
A cup of warm water is suspended in a large pot of water held at a steady boil. Will the water in the cup ever boil? Assume ...
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