Ondol, Korean traditional heating system, has widely been used due to high thermal efficency based on its character of thermal dynamics. it has been also well known Ondol has improved real indoor thermal comfort compared to the other heating systems. Recently, a lot of numerical studies using CFD(Computational Fluid Dynamics) in order to understand interal thermal and flow field has been corned out. In present study, we find out the variation of temporal temperature in floor of traditional Goodie between Jul-Gorae and Doidon-Gorae, we have performed numerical analysis. According to flow rate streams, Weet-mok's temperature in a Doidon-Gorae is 7 t:: higher than Jul-Gorae 's. This asymmetry part has an influence on decreasing a standard deviation of the temperature.

A Zikhwa-Gorae(Directfire-Firetunnel) Gudle is composed in the order of Agungi(Fireplace- gate), Agungi-hureongi(Fireplace-in), Bunengki(Fireridge), Gudle-Gaezari(Gudle-Deepplace), Gorae(Firetunnel), Gorae-Gaezari(Firetunnel-Deepplace), Gulduk(Holebank) and Gusae(Chimney ). The detail drawings of a Gudul(traditional Ondol) are showed. Four kinds of the Gudle are Godeon-Gorae(Straight-Firetunnel) Gudle, Doedon-Gorae(Return-Firetunnel) Gudle and Heutn -Gorae(Scatter-Firetunnel) Gudle.

Gudul has been used since it was invented, and will be used continuously. But recently, we used rarely. One of the this reason is unequally floor temperature in Gudle because the distribution of heating air is not constant. So flow field in Gudul must be known for uniform temperature in floor. Recently, many fluid engineer have been performed the numerical analysis for the understanding of thermal and flow field based on the development of CFD(Computational Fluid Dynamics). In this paper, to find out the variation of temporal temperature in floor of traditional Gudle, we have performed numerical analysis. Initial temperature in floor is 20 t:' after 880 seconds later, maximum temperature become 2i.Oi t:'. ihour later, maximum temperature in floor become 34.5 t:' because continuously increase from 880 seconds.