Numerical Analysis of the Influence of Inner Tubes Arrangement on the Thermal Performance of Thermal Energy Storage Unit

The container shape and arrangement of the thermal storage systems (TES) play a vital role in enhancing thermal performance. In the current investigation, the impact of inner tube dimensions and arrangements of TES on the thermal performance of a PCM-based triplex-tube latent heat storage exchanger (TTHX) is numerically analyzed. COMSOL Multiphysics commercial software was employed to obtain the numerical solution of the governing equations. Eight different cases with the same volume of PCM and various configurations of the inner tubes were investigated. The results of the current study were presented in terms of temperature contours, liquid fraction, Bejan number, average temperature, and average Nusslet number. The shortest melting time was 48 min, which was achieved by a single inner tube configuration with a quicker melting time of >62% compared to other cases. While for multi-tubes, the shortest time was 78 min, which was achieved by the configuration of three tubes (two horizontal and the third placed at the lower section) with an enhancement of melting time reduction of >12% compared to other cases, except for a single inner tube configuration. Regarding the entropy generation, the single tube configuration achieved the lower Bejan number. Therefore, single tube configuration was found to be the best option for maximizing the thermal performance of the studied TTHX

DNA adduct detection: some applications in monitoring exposure to environmental genotoxic chemicals

In the assessment of genotoxic risk factors in the environment, the measurement of DNA adducts in aquatic organisms and in plants may have considerable implications. Using 32P-postlabelling, we have detected DNA adducts in the liver of carp (Chondrostoma nasus) from the River Rhône (France), both downstream and upstream from a polychlorinated biphenyl incineration plant. Some of the DNA adducts were specific to downstream fish, suggesting a differential pattern of exposure. We have also detected DNA damage in needles in a declining spruce forest. We found that, in the declining forest, the amounts of DNA adducts increase in relation to the degree of damage to the needles whereas, in a healthy forest, the levels of DNA adducts were low. We have also found DNA adducts in the leaves of hops grown in fields where heptachlor residues persisted