Hearth and Home Technologies Expedition-I, Manual

Page: 72 / 167

Run 1.xlsm
V
s
– Average gas velocity in the dilution tunnel, ft/sec
ASTM E2515 equations (9)
Where:
v
scent
= Dilution tunnel velocity calculated after the multi-point pitot traverse at the center, ft/sec
v
strav
= Dilution tunnel velocity calculated after the multi-point pitot traverse, ft/sec
k
p
= Pitot tube constant, 85.49
C
p
= Pitot tube coefficient: 0.99, unitless
ΔP*
= Velocity pressure in the dilution tunnel, in H
2
O
T
s
=
Absolute average gas temperature in the dilution tunnel,
°
R; (
°
R =
°
F + 460)
P
s
=
Absolute average gas static pressure in dilution tunnel, = P
bar
+ P
g
, in Hg
P
bar
= Barometric pressure at test site, in. Hg
P
g
=
Static pressure of tunnel, in. H
2
0; (in Hg = in H
2
0/13.6)
M
s
=
Sample calculation:
8.61
9.65
102.4 + 1/2
V
s
= 0.893 x 85.49 x 0.99 x 0.142 x -0.06
13.6
V
s
=
8.66 ft/s
**The dilution tunnel wet molecular weight; M
s
= 28.78 assuming a dry weight of 29 lb/lb-mole
**The ASTM test standard mistakenly identifies Ms as the dry molecular weight. It should be the wet molecular weight as
indicated in EPA Method 2.
Fp = = 0.893
(
460
(
Adjustment factor for pitot tube center point reading =
V
strav
, ASTM E2515 Equation (1)
V
scent
=
F
p
28.78
)
*The ASTM test standard mistakenly has the square root of the average delta p instead of the average of the square root of
delta p. The current EPA Method 2 is also incorrect. This was verified by Mike Toney at EPA.
)
x
30.00 +
s s
avg s
avg p p P s
M P
T
P C k F v

     =
) (
) (
PFS-TECO Page 7 of 15