Greg Harrington
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 Apr 18 comment Thermal resistance of thermal interface materials? Lets say the chip needs to operate at $T_H$ and it dissipates constant 2 W. If we have a low total resistance, then doesnt that make the coolant temperature very close to $T_H$? But you just said you want it as low as possible. This is why I am getting confused Apr 18 asked Thermal resistance of thermal interface materials? Apr 14 asked How do I determine resistivity from electron defects of high purity gold? Apr 14 accepted RMS Free Path vs Mean Free Path Apr 13 comment RMS Free Path vs Mean Free Path I have no idea what to even do with that honestly. I am not a molecular physics guy. I just need to find a formula for RMS free path and there is nothing on google. Apr 13 asked RMS Free Path vs Mean Free Path Apr 11 comment Molecular mean free path probability I'm not really sure what kind of variable the $\xi$ is. It is just the distance the molecule will travel without a collision. I'm guessing it's continuous since it can be 0.01 or 0.012 or 0.013. Are you essentially saying that I should take "at least" and "greater than" to be the same? Apr 11 asked Molecular mean free path probability Apr 8 asked Is my method of calculating thermal conductivity of a metal wrong? Apr 4 awarded Popular Question Apr 4 accepted Help with change in specific volume with time in piston cylinder? Apr 4 comment Help with change in specific volume with time in piston cylinder? WOW. I cannot believe I overlooked that mistake the entire time. Thanks a lot for the help. I also did it the way you mentioned in the endnote and I found it much more convenient Apr 4 comment Help with change in specific volume with time in piston cylinder? I used the quotient rule and obtained $$\frac{d}{dm}(\frac{V(m)}{m})=\frac{m\frac{dV}{dm}-V(m)\frac{d}{dm}(\frac{1}{m}‌​)}{m^2}=\frac{m\frac{dV}{dm}+\frac{1}{m^2}V}{m^2}$$ The only way I could think of expanding $\frac{dV}{dm}$ is by making it $\frac{dV}{dt}\frac{dt}{dm}$ or $\frac{d}{dm}(mv)=v\frac{dm}{dm}+m\frac{dv}{dm}$ which just puts me back to where I began Apr 4 comment Help with change in specific volume with time in piston cylinder? when I used the quotient rule I reached $$\frac{dv}{dm}=\frac{d}{dm}(\frac{V(m)}{m})=\frac{1}{m}\frac{dV}{dm}+\frac{1}{m‌​^4}V(m)$$ and right away I realized I must have done something wrong because I have an $m^4$ when I should. Also, won't $\frac{dV}{dm}=\frac{d}{dm}(mv)$ just get me back to $\frac{dv}{dm}$ which was square one? Apr 4 comment Help with change in specific volume with time in piston cylinder? when I used the quotient rule I reached $$\frac{dv}{dm}=\frac{d}{dm}(\frac{V(m)}{m})=\frac{1}{m}\frac{dV}{dm}+\frac{1}{m‌​^4}V(m)$$ and right away I realized I must have done something wrong because I have an $m^4$ when I should. Also, won't $\frac{dV}{dm}=\frac{d}{dm}(mv)$ just get me back to $\frac{dv}{dm}$ which was square one? Apr 4 asked Help with change in specific volume with time in piston cylinder? Mar 31 comment Which temperature to evaluate fluid properties in pipe? I figured I could use the inlet temperature to find the inlet density and viscosity which would allow me to find the mass flow rate which I know is constant. I would then use the average temperature between inlet and outlet to find the nusselt number. I could then account for property variation from temperature change using $$Nu = Nu_{m}(\frac{\mu_{m}}{\mu_{s}})^{n}$$ Does this sound like a reasonable approach? Or do you think I should evaluate the inlet density at the average of the inlet and the surface temp? Mar 31 asked Which temperature to evaluate fluid properties in pipe? Mar 16 awarded Popular Question Mar 16 awarded Notable Question