Calculate high temperature pipeline temperature decay constants from thermal properties and fluid flow rate for multi layer pipelines, and including internal and external film resistance.
For insulated pipelines and buried pipelines, the internal and external film resistance can often be ignored which provides a simpler calculation. However in some cases the film resistance is required. The internal film resistance can be used for either cooling or heating. The external film resistance should be used for cooling. Use the options with no film resistance to determine whether film resistance is required.
The decay length is only valid provided that the fluid mass flow rate and heat capacity are unchanged. The decay time is valid for any flowrate provided that the fluid heat capacity is unchanged. The overall heat transfer coefficient is calculated relative to the inside diameter of the pipe. The fluid flow rate can be defined either by fluid velocity, fluid volume flow rate, or fluid mass flow rate.
Tool Input
- schdtype : Line Pipe Schedule Type
- diamtype : Line Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
- wtntype : Line Pipe Wall Thickness Type
- tnu : User Defined Wall Thickness
- flowtype : Internal Fluid Flow Type
- Qfu : User Defined Volume Flow Rate
- Mfu : User Defined Mass Flow Rate
- Vfu : User Defined Fluid Velocity
- sectype : Cross Section Type
- OODu : User Defined Outer Diameter Including Coatings)
- Ru : User Defined Total Thermal Resistance
- hrftype : Thermal Resistance Type
- lctype : Decay Constant Type
- Lu* : User Defined Decay Length
- Tu* : User Defined Decay Time
- WTi : Pipe Liner Wall Thickness
- Ki : Pipe And Liner Thermal Conductivity
- WTo : Pipe Coating Wall Thickness
- Ko : Pipe Coating Thermal Conductivity
- Ti : Internal Fluid Temperature
- Ta : External Fluid Ambient Temperature
- ρf : Internal Fluid Density
- Cpf : Internal Fluid Specific Heat Capacity
- Kf : Internal Fluid Heat Conductivity
- μf : Internal Fluid Dynamic Viscosity
- ρe : External Fluid Density
- Cpe : External Fluid Specific Heat Capacity
- Ke : External Fluid Heat Conductivity
- μe : External Fluid Dynamic Viscosity
- βe : External Fluid Expansion Coefficient (Free Convection)
- Ve : External Fluid Velocity
- H : Soil Cover Height To Top Of Pipe
- Ks : Soil Heat Conductivity
Tool Output
- ΔT : Delta Temperature At Inlet
- IID : Pipe Inner Diameter Including Liner
- L* : Decay Length
- Mf : Internal Fluid Mass Flow Rate
- OD : Line Pipe Diameter
- OD/tn : Line Pipe Diameter Over Wall Thickness Ratio
- OOD : Pipe Outer Diameter Including Coatings
- Qf : Internal Fluid Volume Flowrate
- R : Total Thermal Resistance
- Rfi : Internal Film Thermal Resistance
- Rfo : External Film Thermal Resistance
- Rp : Pipe Thermal Resistance
- Rs : Soil Thermal Resistance
- T* : Decay Time
- U : Overall Heat Transfer Coefficient (On IID)
- Vf : Internal Fluid Velocity
- tn : Line Pipe Thickness