Instruction manual

31
where
opid = output identifier (103
⇒
output from table 1, line 3)
day = current day of year
hrmin = time when heat-pulse was fired
tz1_* =
t
z
times for probe 1 (*=1 is the outside depth)
tz2_* =
t
z
times for probe 2 (*=1 is the outside depth)
Step - 3
Just keep appending new data to the bottom of the old input file
6.3. Examining the output file
The analysis programme outputs three calculations of total sap flow, depending on how
the volume sap flux, Q, is determined. In theory, this is given by the integral
Q
r
J
r
dr
H
R
=
∫
2
π
(
)
(7)
for a stem of cambium radius
R
[m] and heartwood radius
H
[m]. In practice, this integral
can be obtained by three different ways, where the operator
<>
will be used to represent
the least-squares fit to the profile data.
Method 1
: Fit the velocity profile and store the data in FILENAME.VEL.
Q
r
J
r
dr
H
R
=
∫
2
π
(
)
(7a)
Method 2: Fit the flux profile and store the data in FILENAME.FLX.
Q
r
J
r
dr
H
R
=
∫
2
π
(
)
(7b)
Method 3: Calculate a weighted sum of velocity, V
i
, times an associated sapwood area, A
i
and store the data in FILENAME.SUM (see Hatton, 1990 and analysis programme for
details of A
i
’s).
Q
A
V
i
i
i
=
∑
(7c)