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  1. Skirmish

    Weird and Deep question about enthalpy...

    So that seems to say to me that even if I have a mulphase/multicomponent system enthalpy h of the whole system can always be calculated has h(T,v)? Is that OK? *I know that h "natural variables" are h(s,P) but it seems that h(T,v) should also work. **There is no reference to chemical nor phase...
  2. Skirmish

    Weird and Deep question about enthalpy...

    The specific issue is with that equation, is a closed system. The thing comes to dependence between P and T. When there is a phase change or a chemical reaction they become dependent and they do not follow the State Postulate that allows one to write h(T;P). If I define h(T;v) then I can use...
  3. Skirmish

    Weird and Deep question about enthalpy...

    I dunno... Assume a constant P calorimeter where liquid water is at 100 ºC and is brought to water vapor also to 100ºc with the mixture of a hot fluid. Calculate Q needed. (enthalpy) *T and P are constant on this process. *We know also that Hv-Hl=L where "L" is the Latent heat, that indeed is...
  4. Skirmish

    Weird and Deep question about enthalpy...

    Yes, to this point I could classify it as a dumb question of mine. But i'm stuck.. There is the catch... In many phase changes, and in many Chemical Reactions we consider P and T constant. But energy change is obviously non-zero and you really have some enthalpy difference. Work is done by...
  5. Skirmish

    Weird and Deep question about enthalpy...

    Supposedly the enthalpy would only depend on the temperature and pressure "h (T, P)" or at least this is how commonly enthalpy is expressed in partial derivatives... So why in an isothermal and isobaric transformation is it different from 0? *We are taliking of real subtances here, nor ideal...
  6. Skirmish

    Roller - Die // Deformation issue

    Compositepro, Hi. Total width is ok (of the complete profile), the problem is only on the bases of the smaller trapezoid. Feed is ok, I mean flow is abundant. Can be it an improper swelling? But its weird because height is ok.
  7. Skirmish

    Roller - Die // Deformation issue

    Hi, thanks for answering. Process parameters are the same, the only thing that changed slightly was the compound.
  8. Skirmish

    Book recommendation on calendering and roller die extrusion

    I'm new on the tyre business and I'must working as a material process technician on those equips. Any gentle soul can recommend me some vital books of those processes?
  9. Skirmish

    Roller - Die // Deformation issue

    Hi, we are having issues with our new roller-die machinery. It is a cold feed extruder with a two rolled calender. Like this image: (with a chiller, and a wind up system) It uses contoured rolls (shells) to produce contoured innerliners: We are having problems with the "trapezoid form"...

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