An inverted pulse tube in which gravity-driven convection is suppressed by acoustic oscillations is analogous to an inverted pendulum that is stabilized by high-frequency vibration of its pivot point. Gravity acts on the gas density gradient arising from the end-to-end temperature gradient in the pulse tube, exerting a force proportional to that density gradient, tending to cause convection whe...

In this study, condensation heat transfer coefficients (HTCs) of HCFC22, HCFC123, HFC134a and HFC245fa are measured on a horizontal plain tube 19.0 mm outside diameter. All data are taken at the vapor temperature of 39 with a wall subcooling temperature 3-8 . Test results show the HTCs of newly developed alternative low vapor pressure refrigerant, HFC245fa, on a smooth tube are 9.5% higher than...

The proximal anastomosis of the apicoarotic bypass is technically demanding. We describe our novel surgical technique to reinforce the proximal anastomosis of the apicoaortic bypass. After moving circular muscle of the left ventricle (LV) under ventricular fibrillation, an inverted tube graft is inserted into LV through the opening of the apex. Then, end-to-end anastomosis is made with horizont...

Nucleate pool boiling heat transfer coefficients of Al2O3-water and TiO2-water nanofluids have been experimentally measured on three horizontal tubes with different materials and similar roughness under atmospheric pressure. Results revealed that the presence of nanoparticles in the base fluid leads to an increase in pool boiling heat transfer coefficients on stainless steel and brass tubes in ...

The present study aimed to test what bonobos (Pan paniscus) understand about contact. The task consisted of a clear horizontal tube containing a piece of food and a stick with a disk attached. The bonobos chose which side to push or pull the stick for the disk to contact the food and make it accessible. There were 9 variations in tube design, which differed in the positions of the stick, disk, ...

In this paper, simulation of natural convection heat transfer from a confined isothermal horizontal elliptic tube based on artificial neural network is presented. The experimental work with changing of all variables is time consuming and expensive and usually has problems associated with it. Experimental data used for the neural network was obtained by a Mach-Zehnder interferometer. In this stu...