# Tag Info

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Both Thermal Conductivity and Specific Heat relate two different quantities, "heat" and "temperature." The point of giving "Thermal Diffusivity" a separate name is that it eliminates the concept of "heat". The "heat equation" $$\frac{\partial T}{\partial t} = \alpha \nabla^2 T$$ reduces two partial ...

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They won't deform by the same amount. Assuming that the horizontally beams are deformable bodies (i.e. not rigid), you can calculate the forces acting on each of the corners by simple statics. Aluminum is experiencing P/2 load on each end, and so is Copper. A difference in Elastic Modulus exist between these two materials, so for the same equal force on both ...

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Imagin the block is heated on the bottom and has expanded to $l+\delta l$, but this expansion tries to expand the top part along with it. So the will be some strain between the hot lower part and the cold top part which will cause stress until the whole block is at temperature $T_i+\delta i$ Some years ago I had to supervise a steel frame structure. They had ...

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The meral bar is not likely to be "fixed" on a base that has less thermal expansion coefficient than it, when the heat reaches the support, it expands too. The source was mainly focused on the longitudinal displacement (1D), but you have a valid point for 3D volume expansion.

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The Mohr circle is a tool that helps visualize the stress state in a location in the structure. The way I interpret it is that each point in the Mohr circle represents the stresses at a rotated coordinate system. (For the 2D case) in two of the orientations (the principal directions), there is no shear stress, while in the 45 degrees to those planes the ...

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(Remote Control) RC servos usually have that type of functionality and they --usually-- use a PWM pulse to control the position. The standard idea is (used to be) that you provide a digital pulse (either Hi or Low) 50 times per second (so the duration of the pulse is 20[ms]). Modern RC servos can be more forgiving and can have different times. The duration ...

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The "professional" version has more features, so the parts have extra information that the student version won't be able to read or convert. So, You will need the "professional" version - at least for complicated parts. If it was just a simple bar it would likely open. You can understand them protecting their software...

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Thermal diffusivity $\alpha\$is: $$\alpha= \frac{k}{\rho*C_p}$$ at constant pressure. k is thermal conductivity (W/(m·K)) $c_{p}$ is specific heat capacity (J/(kg·K)) $\rho$ is density (kg/m3) It is a property indicating how fast say a rod can transfer heat from its hot end to its cold end, conduction. Consider water and air. Air has a higher thermal ...

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I guess nobody knows the analytical answer but I hazard to say the stresses if the support is really kept cool or has a largely smaller thermal index, will be very significant. A large bar with a sudden increase in temperture can even crack at the support or damage the support Roark's formulas for stress and strain had some empirical formulas. I am flying ...

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Perhaps the support bracket accepts radial expansion. Or you could consider that the stress is only being evaluated over the free section and measurement starts a value of x distance from the support. At least that was how we set up our examination of the change in length of a copper bar. I think we had point zero about 2cm from the support and not only was ...

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The deflection of E depends on the L length of the wires. if L is long enough to allow the softer wire to expand ultimately longer than the distance of the beam AB it will never receive half of P and will be just riding along. Most of the load will be carried by the stiffer wire and beam AB will rotate 90 degrees. let's call the stiffness of the wires K1 and ...

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Basically AC and BD can be thought of as two springs. Because the equivalent "spring constant" is given by: $$k_{eq}= \frac{EA}{L}$$ you need to calculate the "spring constant" for copper and aluminium. If the spring constant is the same, then the elongation will be the same. If one of the is larger (e.g. $k_c> k_{al}$), then the ...

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$f = \dfrac {VQ}{Ib}$ is the "shear flow" in the flexural beam element caused by the applied load, and its intensity varies along the beam as the internal shear force $V$ varies. The shear stress is always starting from zero at the free surface because shear occurs at the interface of sliding elements as shown below: Mohr's Circle is used to find ...

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