Post on 01-Jun-2018
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ChBE 2523 Separations
Chapter 10Psychrometric Charts
Spring, 2015
Dr. John Clay
Yesteray yo!
sai tomorro".
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#n a $ighter Sie
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C%&P'E( ) '#P*CS
Drying Overview (9.1, 9.4)Psychrometric Charts (9.3)
Drying Calculations (9., 9.!, 9.")
#y$es o% Dryers (9.2)
Brea+ !p chapter into o!r ierent slie sets
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-oals o $ect!re
&ntro'uce (or review) $sychrometric chartsDi%%erentiate etween the %our 'e%initions o%
humi'ity an' calculate each
se $sychrometric charts to solve 'rying$rolems
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'emperat!res
Dry ul tem$erature, ##em$erature %rom unmo'i%ie' tem$erature sensor
O%ten rea' as *tem$erature+
et ul tem$erature, #w
-tea'ystate none/uilirium tem$erature otaine'when small amount o% water is contacte' un'er
a'iaatic con'itions %rom a small stream o% gas
# 0 (umi'ity) remain constant
Dew $oint tem$erature, #'$#em$erature at which the air ecomes saturate' with
water va$or
Con'ensation will occur i% the moisture content o% the air
stays constant an' the tem$erature 'ro$s elow the'ew oint tem erature
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%!miity
review o% humi'ityumi'ity, g o% water va$or containe' in 1g o%
'ry air
-aturate' humi'ity, s
umi'ity level i% the air was saturate',$$s
Percentage humi'ity, $Com$arison o% the actual humi'ity, ,
to the saturate' humi'ity, s
Percentage relative humi'ity, 5umi'ity re$orte' in terms o% relative
$ressures
& re$ort
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!
== airdrykg
OHkgMM
pPpH
air
water
A
A 2
=
=airdrykg
OHkg
M
M
pP
pH
air
water
As
Ass
2
s
pH
HH 100=
As
AR
p
pH 100=
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%!miity Deinitions
"
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%!miity Charts
umi'ity ($sychrometric) charts6our charts to choose %rom
#e7t
Carrier
aon 8 -&
aon nglish
hy %our charts:
nits-cale
Detail
;
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nother source o% v'ata
hat is 'ry ul
tem$erature:
6igure ;.41, $. 3; 9
%!miity Charts
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hat is asolute humi'ity:
solute umi'ity is to mass %raction (7)
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