Abstract- In this study, Buoyancy driven convection in a rectangular enclosure fitted with a four horizontal adiabatic partition is investigated experimentally for different electrode. The reduced scale test cell , which has an aspect ratio (height/length)Ar of 0.5 and aperture ratio(opening aperture /width)Ap of 0.33,is fitted with the partition midway between two horizontal hot and cold wall. The remaining walls of the enclosure are insulated. Working solution used is aqueous copper sulphate. An electrochemical method based on a diffusion-controlled electrode reaction will be employed in this work for creating the concentration gradient. To visualize the flow, the shadowgraph technique are be used. To understand the flow structure, the temperature distribution and concentration distribution are investigated. The ranges of the parameters in this work are: Ar=0.5, Ap=0.33, Pr=7~8, Sc=1700~2500, N=7.53, Gr,t=8.16×105,Gr,m= 6.15×106 Key words:horizontal adiabatic partition、natural convection、double aperture ratio