Introduction This point is well illustrated by the results

Introduction This point is well illustrated by the results obtained in the experimental study of free convection in a non-rotating cylinder [1], according to which varying the ratio of the physical parameters of the fluid and solid media has a significant impact on the flow structure and on the heat transfer. To date, numerous experimental computational studies have been carried on turbulent Rayleigh–Bénard convection developing in regions with different geometric shapes and in fluids with different Prandtl numbers (see, for example, the review paper [2] containing an extensive reference list). Among these glp-2 cost studies, various experimental works were dedicated to turbulent fluid convection in cylindrical containers with small height-to-diameter ratios and for fluids with Prandtl numbers exceeding unity (these numbers are typical for water, for example). Funfschilling et al. [3,4] presented the results of the recent extensive studies on water convection in non-rotating containers. Water convection in rotating containers was studied in Refs. [5–7]. Considerably fewer studies were dedicated to the consideration of Rayleigh–Bénard convection at low Prandtl numbers. Turbulent convection of mercury in a non-rotating cylindrical container was experimentally studied in Refs. [8,9]. The results of the studies on liquid metal convection in rotating containers filled by mercury have been reported in Refs. [10–12]; the first two of these papers dealt with turbulent Rayleigh–Bénard convection in cavities whose diameter exceeded their height by an order of magnitude, and the third one presented the findings for the case of a rotating cylinder with the height equal to its diameter. The authors of all of the above-mentioned experimental studies have strived to simulate the conditions allowing to neglect the heat transport effects in the walls confining the container. The effect of thermal resistance of the walls on the convection structure and the integral heat transfer has been studied in relatively few papers. Some of the notable experimental works considering the effect of conjugate heat exchange on convection in a cylindrical (non-rotating) container are the detailed studies [1,13], carried out for the media with different Prandtl numbers: Pr= 0.7 [1] and Pr= 4.4 [13]. During the last three decades, turbulent Rayleigh–Bénard convection has been extensively studied by Direct Numerical Simulation (DNS), covering a wide range of Prandtl numbers. A horizontal layer with the periodicity conditions imposed on the vertical boundaries is often considered as the computational domain. The results of detailed computational studies on convection in a stationary horizontal layer at Prandtl numbers about unity are given in [14–17], for the case of a rotating layer. Convection in a stationary layer at low Prandtl numbers was studied by the DNS method in Ref. [14] for Pr= 0.07 with the Rayleigh number Ra ranging from 104 to 107, as well as in Ref. [18] for Pr= 0.025 and Ra=105. The effect of superimposed global rotation was studied in Ref. [19] for Pr= 0.1 and 104≤Ra≤108. The effects of conjugate heat exchange on the structure of turbulent convection and the heat transfer in a Non-rotating horizontal layer, confined by walls of finite thickness, were studied by the DNS method in Ref. [20] for the case of Pr= 0.025, Ra=105. No such investigations have been carried out thus far for the case of a rotating layer. A substantial amount of computational data obtained by the DNS method for turbulent Rayleigh–Bénard convection developing in cylindrical containers (in the non-conjugate problem setting) filled with fluids with significantly varying Prandtl numbers has been accumulated by now (see, for example, Ref. [21], citing numerous experimental and theoretical studies in glomerulus field). The convection in stationary cylindrical containers filled with fluids with the Prandtl number varying from 0.1 to 104 and the Rayleigh number varying from 105 to 109 was considered in Ref. [22]. The results of the DNS computations of turbulent convection in a rotating cylinder with the Prandtl number about unity and 108≤Ra≤109 were presented in Refs. [21,23].