Numerical analysis of the transient turbulent flow field in a thermally stratified thermal storage water tank

Transient numerical analysis was carried out for the replacement process of cold fluid with hot fluid in a thermal storage water tank with a two-dimensional two-equation turbulence model (k-epsilon model). The QUICKEST (QUICK with estimated streaming terms) method was two-dimensionally extended to solve the energy equations. The effect of the difference schemes (the QUICKEST scheme and the upwind scheme) to solve the energy equations was discussed on the transient flow and temperature fields. Comparison with existing experimental results showed that the present numerical approach can fairly predict the characteristics of thermal stratification in a thermal storage water tank.