Ventilation :(Ventilation) :
. .(
).
:
-1
) .(
-2
. .(
-3
)
-1
:(Natural Ventilation )
, (1)
(
)
(1)
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2pg. 2
Ventilation -2
:(Mechanical Ventilation )
.(Exhaust Fans)
,
: (Natural Supply)
) (2)
(Supply Fans)
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,(
(Mechanical Supply)
.(3)
-1
-2
,
/
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3pg. 3
Ventilation
:
,
(Exhaust Fan
)
, .(
-
)
, (Natural Supply)
-
.(
) (4)
-
.
(4)
-
-
-
-
-
-
.
)
: .(
) .(
,
)
,(
.( Eng_most afa84@ya hoo.com
,( (
) )
) /
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,
-1 -2 -3
4pg. 4
Ventilation (Negative Pressure & Positive Pressure ) , (Positive Pressure)
.
Exhaust )
,(Negative Pressure) (Supply Fan)
.
(Fan
,
:(Negative Pressure) ,(850 cfm)
,( 1000 cfm)
(Balance)
,( 5)
,
(
-
)
. (
)
,
.
,(
-
)
:(Positive Pressure) 1150 )
,( 1000 cfm)
150 )
,(6)
,(cfm
, (Balance)
. ,(
(cfm
)
-
.(
(6)
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/
)
(5)
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5pg. 5
Ventilation (Ventilation Calculation) :(Exhaust Air) (
,
(Exhaust Air) (
(
)
)
)
:
:
)
(
:(CFM Exhaust )
)
-
(cfm (m2) (m)
:(Area)
-
: (Height )
-
:(ACH)
-
: (1.7)
-
,(Air change per Hour) (
)
(CFM)
:( ACH) ( ACH)
( Application)
10 to 12
(Toilet )
15 to 20
(Domestic Kitchen )
20 to 30
(Commercial Kitchen)
4 to 6 4 to 6 10
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(Stores) (Car Park ) (Car Park )
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6pg. 6
Ventilation :(Supply Air or Fresh Air) (
,
(
)
) (Supply Air or Fresh Air)
, :
:(Natural Supply)
, ) .(
:(Mechanical Supply)
,(Supply Fan) : (0.85 to 0.90)
:(
-1
) :
,
CFM Supply or Fresh = (0.85 : 0.90) x CFM Exhaust
(1.10 to 1.15)
:(
-2
) :
,
CFM Supply or Fresh = (1.10 : 1.15) x CFM Exhaust
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7pg. 7
Ventilation : ,
( 3.2)
,
( 2.5)
,
( 3.5) .
: (ACH = 15) (CFM exhaust = Area x Height x ACH / 1.7 )
(CFM exhaust = 3.5 x 2.5 x 3.2 x 15 / 1.7 ) (CFM exhaust = 250 )
(250 cfm)
250
-
(Exhaust Fan)
)
.(
(Natural Air)
.(Door Undercut )
15
(250 cfm)
.
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8pg. 8
Ventilation :(Car Park Ventilation) -
, (
(Ducts)
)
-
,(Mechanical Exhaust ) ,(Mechanical Supply)
,(Natural Supply)
. .(Negative Pressure)
-
,
,(High Level) (60cm : 80cm)
.
(Low Level)
:(Fire Mode) , (Variable Speed Fan) : ,
(6 ACH)
,( Exhaust Air) (10 ACH)
. (Variable Speed Fan)
,
6)
-2
(Low Speed) .(Normal Mode)
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(ACH
9pg. 9
Ventilation ,( Smoke Detector)
-3
(High Speed) (Fire Mode)
(10 ACH)
,( Supply Air)
-4 (85% of CFM Exhaust )
.
:
,
4.5
650
,
. :
650 m2 4.5 m 2925 m3 (ACH)
10
6
CFM Ex = 650*4.5*10/1.7
CFM Ex = 650*4.5*6/1.7
= 17,205 CFM
= 10,325 CFM
CFM Sup = 0.85 * 17,205
CFM Sup = 0.85 * 10,325
=14,625 CFM
=8,775 CFM
(Variable Speed Fan)
(Exhaust Air)
(Supply Air)
(Exhaust Fan)
-
(10,325 CFM)
, .(17,205 CFM) (Variable Speed Fan)
(Supply Fan) ,
-
(8,775 CFM)
.(14,625 CFM)
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10pg. 10
Ventilation (Engine Room Ventilation) (ACH)
)
-
.
(
)
-
,500kva
,100kva
70 m2 .(
:(Engine Room Ventilation) .(Radiator Cooling Air)
-1
.(Combustion Air)
-2
Combustion Air
:
(cfm)
(Cooling Air + Combustion Air )
:(CFM)
-
:(H)
-
:(ρ)
-
:(CP)
-
:(ΔT)
-
:(Combustion Air)
-
(Heat Dissipation) (Btu/min) (0.071 lb/ft ³)
(100º F)
(0.24 Btu/LBS/ºF) , (18 to 20 ºF) ,
.(cfm)
,
(Combustion Air)
: ( 1)
:
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(
)
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11pg. 11
Ventilation : (2) (Engine or Generator) .
: (3) ,
) .
,(
: (4) ) .
:
,(
,
:
(ft 2) (CFM) (400:1000 ft/min)
:(A)
-
:(Q)
-
:( ν)
-
: (5) ,(Positive Pressure) (Combustion Air)
(dust and dirt ) .
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12pg. 12
Ventilation : (FG Wilson)
,
4.5
71
,
,1600 Kva
.
: :
CFM
. .
Combustion Air
2843 = 30840 cfm ……………… (1)
:
CFM = CFM Radiator Cooling + CFM Combustion Air Flow CFM = 39199 + 2843 = 42042 cfm ……………. (2) .(42042 cfm) . : 2
2
Area = Q / ν = 42042 / 1000 = 42.042 ft = 3.9 m (3.9 m2) 2
(3.9 m ) ,(50% Free Area)
(Exhaust Air Opening)
-
(Intake Air Opening)
(Louver)
-
(3.9 x 2 = 7.8 m2)
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13pg. 13
Ventilation :(Caterpillar 2015)
(3412 Dita)
-
H=37,478 )
,(CFM or V)
CP=0.24 )
,(R or D=0.071 lb/ ft ³)
,(Btu/min
,(ΔT=20 ºF)
,(Btu/LBS/ºF (Combustion Air)
.(1)
(F)
,(
)
.(CFM = 109970.7)
-
(Fans)
:
(Commercial Kitchen Ventilation)
, .(ACH)
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14pg. 14
