Effect of entropy on Process equipment design
Effect of entropy on Process equipment design
(OP)
Hi Guys,
Can someone help explain to me, in simple terms, the effect of entropy on process equipment design.
thanks
Can someone help explain to me, in simple terms, the effect of entropy on process equipment design.
thanks
Buchi





RE: Effect of entropy on Process equipment design
RE: Effect of entropy on Process equipment design
Entropy increases when heat is transferred across a large temperature difference, or when a pure substance is mixed with other substances to form a mixture, or when a high pressure gas is throttled across an orifice without doing work.
In a simplistic summary, one should configure the process so that heat is transferred across temperature drops that are minimized ( of course this means much more surface areas is needed), and large pressure drops should be accoplished across turbines or pelton wheels instead of acorss orifices or valves ( and this means a higher capital cost for the rotating machinery).
Breaking down the entire process into individual sub-proceses and calculating each sub process's entropy increase should give the analyst a clue as to where the greates potential for cycle efficiency can be found.
RE: Effect of entropy on Process equipment design
When you do the dishes, you start with the not-so-dirty items (the glasses). Gradually you move on to the dirtier things. The dirtiest ones (the horrible frying pan) usually need a two-stage treatment with intermediate replacement of the dishwater.
RE: Effect of entropy on Process equipment design
Just a quick question:
Can you specify your question as we made very generic that you would not get good answers I guess!!
Cheers
RE: Effect of entropy on Process equipment design
Overseas engineers have striven to improve the efficiency of other processes to reduce fuel consumptio and reduce specifc emissions. Some newer terms that are associated with entropy are pinch technology and exergy analysis, and some notable process improvements assocated with those are the use of binary fluids for refrigeration ( Kalina cycles, LNG chillers, modern refrigeration cycles) , and heat exchanger optimization.
RE: Effect of entropy on Process equipment design
Just in general, engineers don't sit around worrying about entropy a lot in a direct way. But entropy ideas are behind a lot of other work that is done.