Questions tagged [thermal-conductivity]
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Thermal conductivity and diffusivity of diatomite (also known as diatomaceous earth or kieselguhr)
Does anyone know where can I find measured thermal conductivity and thermal diffusivity of diatomite for different temperatures? I'm looking for the temperature dependency for temperatures higher than ...
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Possible error in textbook question? (Heat transfer)
I am dealing with either (a) a severe misunderstanding of the question, or (b) a wrong textbook answer.
Here is question verbatim:
A jacketed vessel is used to heat a water stream using steam
...
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IAPWS-IF97 empirical equations for water and steam
IAPWS-IF97 provides empirical equation the dynamic viscosity and the thermal conductivity for water, are there any formulas by IAPWS-IF97 for the density and the specific heat capacity of water?
I ...
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Can a thin stainless steel plate warping and unwarping in a gas oven due to temperature gradients break at some point?
This is in continuation of a previous question:
I have a specially cut 316 stainless steel plate, 345mm diameter * 2mm thicknesses, used in a butane pizza oven that can reach 500 degrees Celsius as a ...
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Effect of specific heat capacity on heat loss
Assume we want to calculate the heat capacities of two substances with different heat capacities. We heat them both up with an immersion heater delivering a constant rate of energy (constant J/s), and ...
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Crucible design for melting alumina
I'd like to melt alumina in a slow, controlled manner.
So I thought a graphite crucible with a tungsten wire wrapped around it for heating would be a good start. To reduce heat losses, I put that ...
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Difference in collision cross-section obtained by measurement method
I have a simple question of Physical Chemistry, but I don't know the answer.
We can find collision cross-section(σ) through experiments in three ways.
first, diffusion flux experiment. diffusion ...
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Electrical and Thermal conductivity of electrum alloys
I have tried to search for this to little effect - I am trying to find electrical and thermal conductivity values for Electrum (a gold and silver alloy). Most sites mention the values depend on the ...
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VO2 unexpected conduction [closed]
$\ce{VO2}$ is a weird metal which becomes a conductor at temperatures higher than $\pu{67 ^\circ C}$, but below $\pu{67 ^\circ C}$, it is an insulator!
How is this possible anyway? This is against ...
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Electrical and thermal conductivity of graphite
I was reading about carbon family where it was mentioned that electrical conductivity of graphite increases with temperature while thermal conductivity decreases.
However, I could not find a suitable ...
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How would a temperature profile in wall change if the rate of heat transfer increases
Given the system below, how would the temperature profile in the wall change if the heat transfer in Fluid II was very fast?
If the heat transfer in Fluid II is very fast, then the T-profile for $\ce{...
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Derive expression for average heat flux in heat exchanger
The single-tube heat exchanger is used to increase the temperature of fluid
I from $T_{b1}$ to $T_{b2}$. The heating oil (fluid II) used
for this task enters at temperature $T_{02}$ and leaves at
...
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Simplifying temperature profile
I am given the temperature profile below and the two equations:
$$Q = (2\pi R_0)LU_0(T_{1\infty}-T_{2\infty})\tag1\label1$$
$$\frac{1}{U_0R_0} = \frac{1}{h_1R_0} +\frac{\ln(R_\mathrm a/R_0)}{k}+ ...
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Derive expression for heat flow from oil bath to metal sphere
A spherical ball of iron is put into a hot bath of oil. The iron ball is initially at a low temperature and heat transfer from the oil to the iron will increase the temperature of the iron ball.
Use ...
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Temperature profile at steady state [closed]
Consider a solid wall consisting of three layers where the layers are of equal
thickness but made out of different materials: $\ce{Layer 1}$ is made out
of copper (high thermal conductivity), $\ce{...
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Determine heat flux from temperature profile
The heating
element and the insulator are of equal thickness L. Heat transfer in
the air film adjacent to the heater is assumed negligible.
I've noticed that I find these type of problem the ...
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Pre-Hydrogen Feature On the Output Of a Gas Chromatography Thermal Conductivity Detector
A candidate for "dark matter", predicted and now apparently detected to have both a higher thermal conductivity and higher diffusion rate than H2 is purported in this PowerPoint Presentation file. ...
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Heat transfer through layered wall
An electrical heater is placed between two layers of insulation. The three layers (the heater and the two layers of insulation) have the same thickness. The figure below shows different temperature ...
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Equation for overall heat transfer coefficient
The heat flow (in $[\pu{J/s}]$) through the wall of a tube of length $L$ and inner radius $R_0$ is
$$Q = (2πR_0L)U(T_{1\infty} - T_{2\infty}),$$
where $T_{1\infty}$ is the bulk temperature in the ...
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Graphite: Thermal and electrical conductivity
I recently encounter this question:
Compare, while providing an explanation, the thermal and electrical conductivity of graphite to that of diamond.
Provided answer:
Graphite conducts electricity(...
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Why would a ~1 cm thick layer of argon be a significantly poorer conductor of heat than air?
In yesterday's new Periodic Video, Argon (new) - Periodic Table of Videos, after about 07 min 00 sec, Sir Martyn Poliakoff says:
The final, and I have to admit perhaps slightly boring application of ...
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