Topology-optimized thermal carpet cloak expressed by an immersed-boundary level-set method via a covariance matrix adaptation evolution strategy. (July 2019)

• Record Type: Journal Article
• Authors: Fujii, Garuda; Akimoto, Youhei
• Is Part Of: International journal of heat and mass transfer. Volume 137(2019)
• Page Start: 1312
• Page End: 1322
• Publication Date: 2019-07
• Subjects: Thermal carpet cloak -- Thermal ground cloak -- Heat manipulation -- Topology optimization -- CMA-ES -- Immersed-boundary level-set method; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2019.03.162
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: This paper presents CMA-ES-based topology optimization for thermal carpet cloaks. An immersed boundary-level set method is used to express the structure of thermal carpet cloaks. Good cloaking performance for heat flowing over a wide angle is numerically realized. Structural data of topology optimized thermal carpet cloaks are provided as supplement. Abstract: Our proposal, a topology optimization method for thermal carpet cloaks, eliminates the disturbance caused by a bump obstacle on a flat boundary and, despite the presence of the bump, reproduces the temperature distribution as if no bump is present. Structural topologies are expressed using an immersed-boundary level-set method and the optimal topologies corresponding to the optimal sets of the level-set functions are explored using the covariance matrix evolution strategy for minimizing the difference between the temperature field under a flat boundary and that for a cloaked bump on the boundary. The difference is evaluated as an objective function and, in the best instance, this function value for the optimal cloak approaches a value 0.000214% of that when no carpet cloak is present around the bump. By moving the location of the heat source, we investigated the performance response of the topology-optimized thermal carpet cloaks for different angles of heat flow. The thermal carpet cloaks presented exhibit good cloaking performance for heat flowing over a wide angle.