Why LMTD is calculated in Heat -Exchanger problems..Why dont
we take average temperature??
Answers were Sorted based on User's Feedback
Answer / bharat
temperature inside heat-exchanger changes exponentially so
taking average would give erroneous results. and LMTD is
calculated by considering a small elemental area of heat
exchanger so it gives more accurate temperature difference.
Is This Answer Correct ? | 40 Yes | 3 No |
Answer / awkash
Because temperature change in heat exchanger is not linear
in nature so we can not take airthmatic mean here,
physically you can think in the manner like if we inlet
temp. of a pipe is 80 and outlet temp. is 40 then u cannot
say that temp in middle will be 60.
thats why for accurte measurement we take lmtd.
Is This Answer Correct ? | 4 Yes | 0 No |
Answer / abina
in heatexchanger temperature changes from point to point along the length so we are calculating Lmtd. ..Bt avg temperature dosnt gv correct value
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / anil
LMTD value it gives the correct average temperature without any errors compare to average temperature
Is This Answer Correct ? | 3 Yes | 16 No |
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