Glass viscosity calculations debunk the myth of flow in medieval windows (2017)

Re:Glass viscosity calculations debunk the myth of flow in m... by pfdietz on Thursday October 29, 2020 @11:03PM (#24938702)

I didn't say compression at a shock was isentropic. I was saying the claim that compression at the shock could not be the cause of (all) the heating, unless you simply define heating at a shock as being due to compression. Instead, I think you should separate out the heating there into two parts: one due to isentropic compression, and one due to injection of additional entropy by dissipation at the shock.

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Re:Glass viscosity calculations debunk the myth of flow in m... by bernulli on Friday October 30, 2020 @06:18PM (#24947400)

Yes you do, you keep repeating that 'proper' compression is isentropic. That's simply not the case, certainly not across a shock.

The second part of your argument is well defined and makes sense, and no-one argued that.

But explain to me again how this is now 'like friction'?

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Re:Glass viscosity calculations debunk the myth of flow in m... by pfdietz on Saturday October 31, 2020 @08:45AM (#24950977)

Requiring compression to be isentropic is just requiring "compression" to be a well-defined term with a specific quantitative result. Otherwise, it's a vague term that offers no quantitative prediction for how much heating it produces for a given change in density. That's not science.

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