Thermal Boundary Layer in the Corner of Two Vertical Right-angled Wall and Horizontal Bottom Wall in Laminar Free Convection

Abstract

Thermal boundary layer in the corner of wall should be taken into account for the accurate calculation of heat transmission through the corner of the wall. However, most studies on thermal boundary layer have concerned flat wall, whether horizontal, vertical, or oblique. Thus, little research has been conducted concerning thermal boundary layer in the corner of wall. In our previous report, we analyzed the thermal boundary layer in the corner of two vertical right-angled wall in laminar free convection. In the present study, we have analyzed the thermal boundary layer in the corner of two vertical right-angled wall and horizontal bottom wall in laminar free convection. Here, thermometry method and formulation method of the shape of the thermal boundary layer in the corner of wall are discussed. Also, measuring the temperature by thermocouple, empirical formula is proposed concerning the thermal boundary layer in the corner of two vartical right-angled wall and horizontal bottom wall in laminar free convection. To ascertain that this empirical formula can be applied irrespective of the difference of temperature between wall surface and the air, verification experiment is conducted, simulated by numerical analysis (Finite Element Method). The results confirms that this empirical formula can be applied in cases where the difference of temperature between wall surface and the air is 15〜80℃.