Coursework Exercise

Coursework Exercise – Thermal Analysis of an Insulated Pipe

In this problem scenario we shall consider the heat loss through a pipe that is used for transporting hot oil emulsion from an oil drilling platform to a remote processing plant. The pipe is constructed from carbon steel and is provided with an insulating sheath to reduce heat loss

The 100 m long, straight pipe is constructed of 10 mm thick, 1% Carbon Steel with an internal radius of 40 mm and outer radius of 50 mm. The pipe is provided with an insulating sheath constructed of 30 mm thick Calcium Silicate.

The following assumptions apply:

  • The oil emulsion (internal pipe surface) is at a temperature of Tr1= 180°C.
  • The external ambient air temperature is Tfl= 24°C
  • The thermal conductivity of 1% Carbon Steel is kPIPE= 43 W/m K (assumed constant under all conditions)
  • The thermal conductivity of Calcium Silicate is kINS= 0.06 W/m K (assumed constant under all conditions)
  • The coefficient of convection describing the heat transfer from the sheath surface to surroundings is h = 150 W/m2K
  • The heat loss by radiation can be considered negligible.

example pipe diagram

© Doug Rattray, LCC, UHI

 

Model the system in the ANSYS software environment and determine:

  1. the temperature on the interface surface between the pipe and the insulated sheath (r2).
  2. the temperature on the outer surface of the insulated sheath (r3).
  3. the heat flux through the pipe.
  4. the energy savings provided by the insulating sheath by comparing the total heat loss per hour through the pipe with and without the insulated sheath attached. Note: assume the coefficient of convection (h) is the same in both scenarios.

Notes

  1. Students should use the coursework report template for writing up results of their modelling activities.
  2. In the report, students should provide evidence of each step of modelling lifecycle in accordance the illustration below; particularly students should provide a detailed description of:
    1. The problem description along with a justification of any assumptions and simplifications.
    2. Hand calculated estimations of the external surface temperature.
    3. The geometric design
    4. Mesh selection
    5. Numerical Results
    6. Comparison of results to verification material
  3. The coursework report template provides additional guidance for students. All guidance should be read in full prior to undertaking the modelling task.
  4. The coursework submission should not be greater than 3000 words.

modelling lifecycle: Problem definition; Pre-processing; Generating the numerical solution; Post-processing.

Recommended Modelling Lifecycle

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