Abstract
This paper introduces a new analytical method for the 3-dimensional analysis of heat sources installed underground. Such sources include primarily electric power cables and steam pipes in urban areas. For complex arrangements of the heat sources, the heat transfer and cable rating calculations require the application of numerical methods, which call for high level of expertise and are generally difficult to use. The computational algorithm presented in this paper uses a point sources approach and is an extension of the work published by the authors based on line source modeling, with the goal of simplifying the numerical calculations. The proposed approach is applicable for all heat sources, which are directly buried in a uniform or a partially dried out soil. The method is illustrated by several numerical examples. These examples are used for comparison with the existing standard approach.
Highlights
Faculty of Electrotechnics, Electronics and Automation, Lodz University of Technology, 90-924 Lodz, Poland; Abstract: This paper introduces a new analytical method for the 3-dimensional analysis of heat sources installed underground
Knowledge of the current carrying capacity of electric power cables, or ampacity for short, is needed when the cable system is designed and it is an important parameter during its operation
The heat transfer inside and outside the cable is described by partial differential equations of heat conduction, which are in principle nonlinear, because of the temperature-dependency of the losses
Summary
The steady-state temperature rise ∆θ caused by a point source is given by:. where r—distance between a point source (with losses W) and the considered point, λ—thermal conductivity of the soil, and c—constant. Where r—distance between a point source (with losses W) and the considered point, λ—thermal conductivity of the soil, and c—constant. W,W, reflected at the soil soil surface. ∆θ caused a point source the soil: the soil:. W) and the reflected source where rr+,,r_r_are arethe thedistances distances between source Equation for temperature the temperature caused by an infinite line source in the soil: caused by an infinite line source in the soil:.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
