m278hlund {pipenostics}

Minenergo-278. Normative heat loss of underground pipe

Description

Calculate normative heat loss of the supplying underground 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

m278hlund(
  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 = 1.74,
  z = 2,
  s = 0.55,
  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]. For underground pipe this is the temperature of subsoil. 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]. Type: 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]. For underground pipe this is the thermal conductivity of subsoil. Type: assert_double.

z

underground laying depth of supplying pipe, [m]. Type: assert_double.

s

distance between supplying and returning pipes, [m]. Type: assert_double.

len

length of supplying pipe, [m]. Type: assert_double.

duration

duration of heat loss, [hour]. Type: assert_double.

Details

Details on using k1 and k2 are the same as for m278hlcha.

Value

Normative heat loss of supplying underground 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.

See Also

Other Minenergo: m278hlair(), m278hlcha(), m278insdata, m278inshcm(), m278soildata, m325beta(), m325nhl(), m325nhldata, m325testbench

Examples

 library(pipenostics)

 m278hlund()
 # [1] 102.6226