Calculate normative heat loss of the open-air supplying pipe as a function of construction, operation, and technical condition specifications according to Appendix 5.1 of Minenergo Method 278.
This type of calculations is usually made on design stage of district heating network (where water is a heat carrier) and is closely related to building codes and regulations.
Usage
m278hlair(
t1 = 110,
t2 = 60,
t0 = 5,
insd1 = 0.1,
insd2 = insd1,
d1 = 0.25,
d2 = d1,
lambda1 = 0.09,
lambda2 = 0.07,
k1 = 1,
k2 = k1,
lambda0 = 26,
len = 1,
duration = 1
)Arguments
- t1
temperature of heat carrier (water) inside the supplying pipe, [°C]. Type:
assert_double.- t2
temperature of heat carrier (water) inside the returning pipe, [°C]. Type:
assert_double.- t0
temperature of environment, [°C]. In case of open-air pipe this is the ambient temperature. Type:
assert_double.- insd1
thickness of the insulator which covers the supplying pipe, [m]. Type:
assert_double.- insd2
thickness of the insulator which covers the returning pipe, [m]. Type:
assert_double.- d1
outside diameter of supplying pipe, [m]. Type:
assert_double.- d2
outside diameter of returning pipe, [m]. Type:
assert_double.- lambda1
thermal conductivity of insulator which covers the supplying pipe [W/m/°C]. Type:
assert_double.- lambda2
thermal conductivity of insulator which covers the returning pipe [W/m/°C].
assert_double.- k1
technical condition factor for insulator of supplying pipe, []. Type:
assert_double.- k2
technical condition factor for insulator of returning pipe, []. Type:
assert_double.- lambda0
thermal conductivity of environment, [W/m/°C]. In case of overhead laying this is the thermal conductivity of open air. Type:
assert_double.- len
length of supplying pipe, [m]. Type:
assert_double.- duration
duration of heat loss, [hour]. Type:
assert_double.
Value
Normative heat loss of the open-air layed supplying cylindrical pipe
during duration, [kcal].
If len of pipe is 1 m (meter) as well as duration is set to
1 h (hour) (default values) then the return value is also the
specific heat loss power, [kcal/m/h] and so comparable with those
prescribed by Minenergo Order 325.
Type: assert_double.
Details
Details on using k1 and k2 are the same as for
m278hlcha.
See also
Other Minenergo:
m278hlcha(),
m278hlund(),
m278insdata,
m278inshcm(),
m278soildata,
m325beta(),
m325nhl(),
m325nhldata,
m325testbench
Examples
library(pipenostics)
m278hlair()
#> [1] 138.7736
# [1] 138.7736