Latexman,
Thank you for your suggestion. Interestingly enough I did it the way you suggested, as well as breaking it up into nodes, and both results only differ by about 4% (though I could iterate further and get it a little closer).
Thanks for your help!
What I am attempting to do now, in leiu of simulation software, is break up the piping in nodes with K < 100, changing the specific volume accordingly...
E.g.
Largest diameter of pipe in system is 3.94 ID.
One section of pipe in the system is 330 ft of 2.067 ID pipe.
Beta = 2.067/3.94= 0.525
If Moody friction factor = 0.020, then:
K= 12*0.020*330/(2.067*0.525^4) = 497
Just this section alone has K greater than 100. Adding up the other...
Hello All,
My brain's a little fuzzy this afternoon, but I'm running into a problem with Crane T.P. No. 410, pg. A-22 "Net Expansion factor Y for Compressible Flow..."
For my example:
P1 = 40 psig + 14.7 = 54.7 psia
P2 = 0.397 psig + 14.7 = 15.097 psia
DP = 39.603 psia
DP/P1 = 0.724
K = 752...
We are going to use a 1500 gal. tank as a mineral oil hold tank; totes of mineral oil will be pumped into the tank and mineral oil will be metered from the tank for various uses. The only "process" in the tank will be to heat it to 100C while sparging N2 to drive off enough entrained water to...
Hi All,
We have a knockoutpot which takes in multiple reactor vapor vents (typically set to 1 psig or a few oz's) from a different building. Each vent line typically connects vents from multiple reactor sources. Great pains have been taken to ensure that for each vent line to the...
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I noticed that between the 6th and 7th editions of API 520, part 1, that External Fire sizing on process vessels has been omitted. Specifically, the 6th edition includes 'Appendix D-Determination of Fire-Relief Requirements' wherein the heat load due to fire on the wetted vessel surfaces can be...
Stab in the dark:
A client has a 3-way safety selector valve with (2) relief valves, circa 1960s, on a 75 psig steam line. They want to replace the 3-way and eventually the relief valves (down the road). The failure scenario is a failure of the 300 psig/75 psig pressure reducing station OR...
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The relief is calculated to be relatively small (<3GPM liquid at the RV inlet) through a 1/2" x...