dropt {pipenostics}

Temperature drop in cylindrical steel pipe due heat loss

Description

Calculate temperature drop in steel pipe of district heating system (where water is a heat carrier) that is a result of heat loss through pipe wall and insulation.

Usage

dropt(
  temperature = 130,
  pressure = mpa_kgf(6),
  flow_rate = 250,
  loss_power = 7000
)

Arguments

temperature

temperature of heat carrier (water) inside the pipe measured at the inlet of pipe, [°C]. Type: assert_double.

pressure

absolute pressure of heat carrier (water) inside the pipe, [MPa]. Type: assert_double.

flow_rate

amount of heat carrier (water) that is transferred by pipe during a period, [ton/hour]. Type: assert_double.

loss_power

power of heat loss - heat loss through area of pipe wall per hour, [kcal/hour]. Type: assert_double.

Details

Specific isobaric heat capacity used in calculations is calculated according to IAPWS R7-97(2012) for Region 1 since it is assumed that state of water in district heating system is always in that region.

Value

temperature drop at the outlet of pipe, [°C]. Type: assert_double.

See Also

Other district heating: dropg(), dropp()

Examples

 library(pipenostics)

 # Calculate normative temperature drop based on Minenergo-325 for pipe segment
 pipeline <- list(
   year   = 1968,
   laying = "channel",
   d      = 700, # [mm]
   len    = 1000 # [m]
 )

 regime <- list(
   temperature = c(130, 150), # [°C]
   pressure    = .588399,     # [MPa]
   flow_rate   = 250          # [ton/hour]
 )

 pipe_loss_power <- do.call(
     m325nhl,
     c(pipeline, temperature = list(regime[["temperature"]]), duration = 1)  # [kcal/hour]
 )

 temperature_drop <- dropt(
   temperature = regime[["temperature"]], # [°C]
   loss_power  = pipe_loss_power          # [kcal/hour]
 )                                        # [°C]

 print(temperature_drop)

 # [1] 1.366806 1.433840