Celal Bayar University

About: Celal Bayar University is a education organization based out in Magnesia ad Sipylum, Turkey. It is known for research contribution in the topics: Population & Heat transfer. The organization has 2960 authors who have published 6024 publications receiving 100646 citations.

Fluid–structure-magnetic field interaction in a nanofluid filled lid-driven cavity with flexible side wall

Abstract: In this study MHD flow in a lid driven nanofluid filled square cavity with a flexible side wall is numerically investigated. The top wall of the cavity is colder than the bottom wall and it moves in the + x direction with constant speed. Other walls of the cavity are insulated. The finite element formulation is utilized to solve the governing equations. The Arbitrary-Lagrangian-Eulerian method is used to describe the fluid motion with the flexible wall of the cavity in the fluid–structure interaction model. The influence of the Young’s modulus of the flexible wall on the flow and heat transfer characteristics are numerically investigated for the following parameters: ( 10 4 N / m 2 ≤ E ≤ 2.5 × 10 5 N / m 2 ), with a Richardson number of ( 0.01 ≤ R i ≤ 5 ), a Hartmann number of ( 0 ≤ H a ≤ 50 ) and a volume fraction of the solid particles given by ( 0 ≤ ϕ ≤ 0.04 ). The effect of Brownian motion on the effective thermal conductivity of the nanofluid is taken into account. Averaged heat transfer decreases with increasing Hartmann number and decreasing Richardson numbers. As the Young’s modulus of the flexible wall decreases, the averaged heat transfer increases and 66.5% of the heat transfer enhancement is obtained for E = 10 4 N/m 2 compared with E = 2.5 × 10 5 N/m 2 . An averaged heat transfer enhancement of 33.87% is obtained for a solid volume fraction of 4% compared to the base fluid for the fluid–structure model coupled with the magnetic field.

Effects of high altitude on sleep and respiratory system and theirs adaptations.

Abstract: High-altitude (HA) environments have adverse effects on the normal functioning body of people accustomed to living at low altitudes because of the change in barometric pressure which causes decrease in the amount of oxygen leading to hypobaric hypoxia. Sustained exposure to hypoxia has adverse effects on body weight, muscle structure and exercise capacity, mental functioning, and sleep quality. The most important step of acclimatization is the hyperventilation which is achieved by hypoxic ventilatory response of the peripheral chemoreceptors. Hyperventilation results in increase in arterial carbondioxide concentration. Altitude also affects sleep and cardiac output, which is the other determinant of oxygen delivery. Upon initial exposure to HA, the resting pulse rate increases rapidly, but with acclimatization, heart rate and cardiac output tend to fall. Another important component that leads to decrease in cardiac output is the reduction in the stroke volume with acclimatization. During sleep at HA, the levels of CO2 in the blood can drop very low and this can switch off the drive to breathe. Only after the body senses a further drop in O2 levels breathing is started again. Periodic breathing is thought to result from instability in the control system through the hypoxic drive or the response to CO2.