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MikeGlass1969

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About MikeGlass1969

  • Rank
    Project Manager

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  • Gender
    Male
  • Location
    Butler, PA

Previous Fields

  • Engineering Field
    HVAC&R
  • License
    PE
  • Calculator
    HP
  • Discipline
    Mechanical

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  1. MikeGlass1969

    TFS Lindeburg #33

    Slay, I think 6.4 is a typo. I looked up the Leq for the elbows and was only 4.6 ft each. He is also using "typcial loss coefficients" from table 17.4 in the MERM. I looked at the problem earlier. I had some questions too. Is the Kentrance given as .5? Why could we not use a leq=9.5 ft from A-54 in MERM. It is a square mouth inlet.
  2. MikeGlass1969

    TFS practice problem of the week...

    OHHH!!!!! ... Now I see it.
  3. MikeGlass1969

    TFS practice problem of the week...

    I am looking at the external pipe heat transfer. With an 80F external wall pipe temperature in a space that is somewhat colder that -320F. There should be an increased transfer rate above that of the radiant heat transfer: (a) natural convection - Assuming no velocity is induced from the expansion of the Nitrogen (b) quasi forced convection from the expansion of Nitrogen. Hope that makes sense...
  4. MikeGlass1969

    TFS practice problem of the week...

    I just think problem needs to state, neglect the convective heat transfer...
  5. MikeGlass1969

    TFS practice problem of the week...

    So we were to ignore the convective heat transfer portion of the problem? The flashing of the Nitrogen should have induced a velocity in the chamber and enhanced the heat transfer. Similar to example 37.1 in MERM... On page 37-4 thru 37-6.
  6. MikeGlass1969

    TFS practice problem of the week...

    I would like to see the solution for this... I must be making this more difficult than what it is.
  7. MikeGlass1969

    HVAC&R Practice Problem of the week

    I used 71F for the Tdp... I got 9.3F. But when I substitute in 70.2F I get -3.8F Pretty large swing. All answers were possible in this problem
  8. MikeGlass1969

    HVAC&R Practice Problem of the week

    Slay, I tried this... However I converted the straight pipe, for each branch, into a K and summed all the K's for each branch. Plugged into the Bernoulli equation. And Came up with something in the area of (B). But, in the TFS the answer was reported as (D). In the solution posted in the other forum, added the head losses from friction in the energy equation. Why? Shouldn't they be subtracted? I found a mistake, got 93ft which is close to (D)
  9. MikeGlass1969

    HVAC&R Practice Problem of the week

    I got something less than (D)
  10. MikeGlass1969

    MD&M practice problem of the week

    I tried this too, and I am not getting it, either.
  11. MikeGlass1969

    MD&M practice problem of the week

    Nice! I am envious of your knowledge and penmanship.
  12. MikeGlass1969

    MD&M practice problem of the week

    OOF!!! I can not remember how to approach these problems... Partial Credit Given?
  13. MikeGlass1969

    Fluid Mechanics & Hydraulics for TFS Contest

    Welcome Vitalvi...
  14. I would actually recommend using the ASHRAE Chart, as that is what you will see on the exam.
  15. Two air streams are mixed: (A) is 5000 ft^3/min @ 40Fdb/35Fwb (B) is 15000 ft^3/min @ 75Fdb/50% rh Find the mixed dry bulb temperature. The specific volume for stream B @ 75Fdb/50%rh = ~ 13.7 ft^3/lbm Try using the psych chart in the MERM 13 Appendix A-137 it has 0.1 graduations for specif volume.
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