Application of field fire modeling to validate structural fire protection for cable ducts in nuclear power plants

Introduction. This article presents the validation of using field fire modeling to evaluate the effectiveness of structural fire protection for cable ducts in nuclear power plant (NPP) premises.

Aim. This article aims to provide computational and analytical validation of design solutions for protecting safety systems, particularly the physical separation of cable routes for different safety channels.

Materials and methods. In this study, the field method was used to calculate local fire parameters within cable structures made from fire-resistant materials with a regulated fire resistance limit.

Results. Based on an analysis of experimental data regarding the development of fires in enclosed cable routes, conclusions were drawn about the specifics of fire development within cable trays. Computational and analytical studies that used the field method to calculate fire dynamics expanded the scope of the research and identified typical fire parameters in cable trays made from modern, fire-resistant materials. The analytical method presented in this article was employed to validate the effectiveness of structural fire protection for cable ducts in NPP premises.

Conclusions. Computational and analytical studies of fire behavior in cable ducts are important for developing design solutions for constructing, reconstructing, and making major repairs to cable systems in nuclear power plants. These studies can validate fire protection requirements for cable routes and structures during the design and construction of NPP. The results may also be used to develop or refine regulatory documents that ensure fire safety in NPPs under construction. The results are also relevant for developing design solutions for constructing, reconstructing, and making major repairs to cable systems, as well as for replacing and re-laying cable products in operating NPPs.

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