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This research presents the outputs for nano-refrigerant (R600a/oil/CuO) boiling heat transfer within flattened channels utilizing experimental method. The influence of flattened percentage, flow rate, vapor quality as well as the mass fraction of CuO on boiling heat transfer (h) were discussed. Outcomes reveal that increasing the flattened percentage enhances the h. Also, within the ranges of present experiment, h augments by increasing nanoparticle's concentration.

Heat transfer intensification is significant for enhancement of the performance of various industrial uses such as condensers. In addition, the presence of nanofluid considerably increases the thermal features of carrier fluid. In current paper, CuO nanoparticles involving different shapes have been employed for heat transfer augmentation in wavy channel with obstacles. This work tries to focus on the main flow pattern and indicate the highest operative terms on the heat rate. In order to do this, computational simulation was applied to simulate hydrothermal behavior. Significant parameter studies were performed to investigate the influences of wavelength and height ratios and velocity inlet. According to obtained results, suitable formula for Nusselt number is offered. Outputs show that Nu goes up with augment of height of obstacle due to increasing in strength of intensity. Also, thinner temperature boundary layer thickness can be seen for greater wavelength ratio. Our finding reveals that heat transfer rate increases more than 55% as the spherical nanoparticles is replace by platelet ones.

Parametric studies on the optimization of baffles on vibration suppression of partially filled tanks coupled by structure have been widely conducted in literature. However, few studies focus on the effect of the position of the baffles on fluid flow stratification and dampening the motion. In the present study, a numerical investigation, an engineering analysis, and optimal design study were performed to determine the effect of external flow on circular obstacle baffles performance on suppressing the vibrations of coupled structure in a closed basin. The single degree of freedom model (mass-spring-damper) is used to model the structure that holds the tank. The coupled system is released from an initial displacement without a velocity. The governing mass, turbulent Navier-Stokes momentum, volume of fluid, and one degree of freedom structure equations are solved by the Pressure-Implicit with Splitting of Operators algorithm in fluids and Newmark method in structure. Based on a detailed study of transient structure motion coupled with sloshing dynamics, the optimal baffle location was achieved. Optimal position of the baffle and its width are systematically obtained with reference to the quiescent free surface., Air Transport & Operations