Fulfilled R&D projects

Simulation of the freezing halo and thawing of soils contiguous to the North-European gas pipeline as a result of seasonal and technological change of gas temperature

Keywords North-European gas pipeline, soil, gas pipeline coating, transient non-linear heat transfer, phase transition, gas pipeline freezing, climatic conditions, gas temperature, frozen layer thickness, frost protrusion, gas pipeline displacement
Programs in use ANSYS

CompMechLab in 2007 executed computational analysis supposed to define the halo of freezing and thawing of soils contiguous to the North-European gas pipeline for different climatic conditions during a year. Gas pipeline possible displacement computation (taking soils frost protrusion in the most dangerous sections during a year into consideration) is executed.

In this work mathematical and finite element models (intended for transient non-linear heat transfer state in gas pipeline and its contiguous soils, as well as the soils and gas pipeline stress analysis) are elaborated.

Coastal pipeline trench cut. Typical sections
Coastal pipeline trench cut. Typical sections

One of soil computational sections finite element model
One of soil computational sections finite element model

In this work the gas pipeline haloes of freezing (during the same year various moments of time and taking various climatic conditions into consideration) are analyzed. The biggest areas of soil freezing around the gas pipeline are revealed.

Characteristic soils (contiguous to the gas pipeline) temperature distribution
Characteristic soils (contiguous to the gas pipeline) temperature distribution

Characteristic halo of soils (contiguous to the gas pipeline) freezing (red color)
Characteristic halo of soils (contiguous to the gas pipeline) freezing (red color)

North-European gas pipeline vertical displacement definition for the area with the biggest zone of soil freezing (when transported gas temperature conditions change seasonally) is carried out.

Gas pipeline vertical displacement. Soil frost protrusion
Gas pipeline vertical displacement. Soil frost protrusion

On the basis of executed work halo of freezing and possible gas pipeline vertical displacements negative influences minimization recommendations are developed.