Thermal management in a biological tissue in order to destroy tissue under local heating process

In this study, the thermal management in a biological tissue in order to destroy tissue under local heating process is carried out. A trocar is used as a tool to destroy tissue in the liver that is connected to a power supply. The trocar is made up of different tines, also called electrodes. In this study, five different types of tines are investigated, which include single-tine, two-tine, three-tine, four-tine, and five-tine. The performance of each trocar on the degradation process is studied from a thermal point of view. The electrical potential and temperature distribution within the tissue are investigated according to different trocars. The results show that the use of five-tine has a better performance on tissue destruction. In contrast, the use of a single-tine can be used by the physician to better control the heat and glands small enough in the tissue. Besides, the heat and the destruction can be controlled by the operating voltage of the power supply. The temperature distribution inside the tissue is quasi-steady from the seventh minute onwards and no significant change is observed in the maximum temperature inside the tissue. The results show that the increase in temperature from 16 V to 18 V is equal to 11.76%

Mixed convection of non-Newtonian nanofluid in an H-shaped cavity with cooler and heater cylinders filled by a porous material: Two phase approach

In the present problem, two-phase mixed convection of a non-Newtonian nanofluid in a porous H-shaped cavity is studied. Inside the enclosure there are four rotating cylinders, using the Boussinesq approximation, mixed convection is created. Nanofluid includes H2O + 0.5% CMC and copper oxide nanoparticles. The mixture model was used to model physical phenomena. Different aspect ratios were used in order to achieve the best heat transfer rate. The Darcy and Richardson numbers ranges are 10−4 ≤ Da ≤ 10−2 and 1 ≤ Ri ≤ 100 respectively. Also, the aspect ratio and dimensionless angular velocities of cylinders ranges are 1.4 ≤ AR ≤ 1.6 and −10 ≤ Ω ≤ 10 respectively. Streamlines and isotherm-lines contours have been obtained for the variation of Darcy and Richardson numbers, aspect ratio and angular velocity. The heat transfer rates have been obtained for various aspect ratios, Darcy and Richardson numbers, and the direction of the cylinder\u27s rotation, and are compared with each other. The results show that the direction of cylinders rotation influences the strength and extent of the generation vortices. Also, the use of porous material in high permeability can be a good alternative to lowering the angular velocity of the cylinders and ultimately reducing the need for less energy