This presentation was made at the 2019 NAFEMS World Congress in Quebec Canada
Haeinsa is one of the most famous temples in South Korea and was assigned as a UNESCO World Heritage Site in 1995. Tripitaka Koreana is a Korean collection of the Tripitaka carved onto 81,258 wooden printing blocks in the 13th century, and it has been assigned as a National Treasure of Korea. One of buildings in the Haeinsa temple, Janggyeongpan-Jeon, has preserved the Tripitaka Koreana from any significant damage for over 750 years. It is accepted that the ventilation condition of the building, which has preserved the Tripitaka Koreana, is naturally very effective. However, there have not been any scientific investigations to study this. Recently, scientific studies have been conducted to clarify the secrets of the preservation environment at Janggyeongpan-Jeon. However, these studies showed airflow performance inside and outside the building using a roughly modelled three-dimensional (3D) geometry. In this work, computational fluid dynamics (CFD) simulations with a higher accuracy on an adaptive Cartesian mesh structure were performed to investigate the characteristics of the airflow inside and outside Janggyeongpan-Jeon. Because of complex real geometries of Janggyeongpan-Jeon, the finite volume approach implemented on the adaptive Cartesian mesh system was used for airflow simulations. An aerodynamic analysis for one of the buildings of Janggyeongpan-Jeon, known as Bubbo-Jeon, was undertaken first to examine the airflow performance inside the building. In this simulation, the precisely modelled geometry of windows and bookshelves in the building was considered. After simulation results for Bubbo-Jeon were obtained, CFD simulations for all building structures were performed using a far greater number of computational cells than those used in the case of a single building. The results show that ventilation inside the building works well even though the wind direction may change seasonally. Parallel computations for CFD of the whole building were made on 64 core clusters, and approximately 23 million cells were used to accurately simulate the flow characteristics even for a complex fluid domain because of the full modeling of the Janggyeongpan-Jeon geometry. Although the magnitude of the air velocity inside the building is influenced by changes in the external wind direction, no flow stagnated area was found inside the building, implying that natural ventilation is effective. This work presents a successful example, indicating that the finite volume approach on an adaptive Cartesian mesh is an efficient way to simulate fluid flow for complex geometries.
|Date||18th June 2019|