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Title: Tree-Shaped Fluid Flow and Heat Storage in a Conducting Solid

Journal Article · · Journal of Applied Physics
DOI:https://doi.org/10.1063/1.3671672· OSTI ID:1036388

This paper documents the time-dependent thermal interaction between a fluid stream configured as a plane tree of varying complexity embedded in a conducting solid with finite volume and insulated boundaries. The time scales of the convection-conduction phenomenon are identified. Two-dimensional and three-dimensional configurations are simulated numerically. The number of length scales of the tree architecture varies from one to four. The results show that the heat transfer density increases, and the time of approach to equilibrium decreases as the complexity of the tree designs increases. These results are then formulated in the classical notation of energy storage by sensible heating, which shows that the effective number of heat transfer units increases as the complexity of the tree design increases. The complexity of heat transfer designs in many applications is constrained by first cost and operating cost considerations. This work provides a fundamental basis for objective evaluation of cost and performance tradeoffs in thermal design of energy systems with complexity as an unconstrained parameter that can be actively varied over a broad range to determine the optimum system design.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
DOE Contract Number:
AC36-08GO28308
OSTI ID:
1036388
Report Number(s):
NREL/JA-5500-54302; JAPIAU; TRN: US201206%%267
Journal Information:
Journal of Applied Physics, Vol. 111, Issue 1; Related Information: Article No. 014902; ISSN 0021-8979
Country of Publication:
United States
Language:
English

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