Planning Drop Downs
EaVc i]Z Ygde Ydlch [dg ZVX] bVX]^cZ! jh^c\ | |
WaVhi\ViZhl]ZgZkZgedhh^WaZidXdcigdaV^g[adl# | |
G^\^YE^eZ | :aWdl |
| |
BV^cA^cZ |
|
N7gVcX] | G^\^YE^eZ |
| |
8aVbe | 7aVhi<ViZ |
| |
;aZmE^eZ |
|
IdEaVcZg |
|
Figure 52.9gdeYdlchZije# |
Calculating Duct Resistance
6YY^c\ YjXi ldg`! ZaWdlh! WgVcX]Zh VcY Vcn di]ZgXdbedcZcihidVYjXia^cZ^cXgZVhZhV^g[adl gZh^hiVcXZ hiVi^X egZhhjgZ adhh# I]^h gZh^hiVcXZ XVcWZb^c^b^oZYWnjh^c\g^\^Yhbddi]e^eZVcY \gVYjVa XjgkZh! Vh deedhZY id [aZm^WaZ e^eZ VcY
.%ßZaWdlh#
Id ]Zae ndj i]^c` VWdji i]^h gZh^hiVcXZ! ^bV\^cZ g^Y^c\VW^XnXaZ^cVijccZai]Vi^hVcZmVXigZea^XV d[ndjgYjXildg`#>[i]Z^ch^YZd[i]ZijccZa^hkZgn Wjben[aZm^WaZe^eZVcY]VhVadid[h]Vgeijgch .%ßZaWdlh!^il^aaiV`ZVadibdgZZ[[dgiidigVkZa [gdbdcZZcYidi]Zdi]Zg#
I]Z ejgedhZ d[ XVaXjaVi^c\ i]Z gZh^hiVcXZ ^h id YZiZgb^cZ^[^i^hadlZcdj\][gdbi]ZbVX]^cZid i]ZYjhiXdaaZXidgidbZZii]Z\^kZc8;BgZfj^gZ" bZci[dgi]ZbVX]^cZ#JhZi]Z[daadl^c\iVWaZhid XVaXjaViZi]ZgZh^hiVcXZd[YjXildg`#
Duct | Approximate | Approximate | ||
Dia. | Static Pressure | Static Pressure | ||
| Loss Per Foot of | Loss Per Foot | ||
| Rigid Pipe | of Flex Pipe | ||
| BV^c | 7gVcX] | BV^c | 7gVcX] |
| A^cZh | A^cZh | A^cZh | A^cZh |
| Vi(*%% | Vi)%%% | Vi(*%% | Vi)%%% |
| ;EB | ;EB | ;EB | ;EB |
' | %#%.& | %#&'' | %#(* | %#)*( |
'#* | %#%- | %#&%, | %#(%+ | %#(., |
( | %#%,& | %#%.) | %#',& | %#(*' |
) | %#%*, | %#%,* | %#'&* | %#'- |
* | %#%)+ | %#%*. | %#&,' | %#''* |
+ | %#%(, | %#%), | %#&(+ | %#&- |
, | %#%'. | %#%(+ | %#&%+ | %#&)& |
%#%'( | %#%', | %#%- | %#&%- | |
. | %#%&, | %#%&. | %#%*, | %#%,. |
|
|
|
|
|
Fitting | 90˚ | 45˚ | 45˚ | 90˚ |
Dia. | Elbow | Elbow | Wye(Y) | Wye(Y) |
|
|
|
|
|
( | %#), | %#'(* | ||
) | %#)* | %#''* | %#(,* | %#''* |
* | %#*(& | %#'++ | %#(*) | %#'(+ |
+ | %#*+) | %#('. | %#'(* | |
, | %#)+- | %#'() | %#(') | %#'&+ |
%#)%* | %#'%( | %#'., |
Figure 53. HiVi^XegZhhjgZadhhX]Vgih#
>cbdhihbVaa$bZY^jbh]deh^i^hdcancZXZhhVgn idXVaXjaViZi]Za^cZl^i]i]Zadc\ZhiYjXiaZc\i]dg i]Zbdhi[^ii^c\hdeZgVi^c\jcYZgi]ZVhhjbei^dc i]Vi^[i]Za^cZl^i]i]Z]^\]ZhigZh^hiVcXZldg`h! i]Zdi]Zghl^aaWZ[^cZ#
To calculate the static pressure of any given line in the system, follow these steps:
1. BV`Z V a^hi d[ ZVX] h^oZ YjXi ^c i]Z a^cZ! ^cXajY^c\i]ZaZc\i]!VcYbjai^eani]dhZcjb" WZghWni]ZhiVi^XegZhhjgZkVajZ\^kZc^ci]Z egZk^djhiVWaZ#
2. A^hiZVX]ineZd[ZaWdldgWgVcX]VcYbjai^ean i]Z fjVci^in^[ bdgZ i]Vc dcZ Wn i]Z hiVi^X egZhhjgZadhh\^kZc^ci]ZegZk^djhiVWaZ#
"(%" |