One of the major industry problems is the flow boiling, where reaching to the critical heat flux (CHF) condition can lead to a temperature jump and damage of the systems. In the present study, the effects of a uniform change in tube diameter on subcooled flow boiling and CHF was numerically investigated. The Euler-Euler model was used to investigate the relationship between the two liquid and v...

Longitudinal heat conduction is an important parameter in the cryogenic field, especially in cryogenic heat exchangers. In the present work, the parasitic effect of tube wall longitudinal heat conduction on temperature measurement has been studied in cryogenic laminar hydrogen flow. The effects of various parameters such as wall cold end temperature, wall thermal conductivity, gas volumetric fl...

Experimental and computational studies were performed to elucidate the role of turbulent stresses in mechanical blood damage (hemolysis). A suspension of bovine red blood cells (RBC) was driven through a closed circulating loop by a centrifugal pump. A small capillary tube (inner diameter 1 mm and length 70 mm) was incorporated into the circulating loop via tapered connectors. The suspension of...

The flow behavior around a cam shaped tube in cross flow has been investigated experimentally using flow visualization and pressure distribution measurement. The range of attack angle and Reynolds number based on an equivalent circular diameter are within 0 ≤ α ≤ 360˚ and 2 x 104 < Reeq < 3.4 x 104, respectively. The pressure drag features are clarified in relation to the flow behavior around t...

This paper describes a low-temperature dielectric barrier discharge (DBD)-plasma induced vaporization technique using mercury as a model analyte. The evaporation and atomization of dissolved mercury species in the sample solution can be achieved rapidly in one step, allowing mercury to be directly detected by atomic fluorescence spectrometry. The DBD plasma was generated concentrically in-betwe...

BACKGROUND The CoughAssist is a mechanical insufflator-exsufflator designed to assist airway secretion clearance in patients with ineffective cough. The device may benefit intubated and tracheotomized patients. We assessed the impact of various artificial airways on peak expiratory flow (PEF) with the CoughAssist. METHODS We measured PEF and pressure at the airway opening in a lung model duri...

where di and dO are the inner tube and outer tube diameters, respectively. The diameter of the inner tube (di) and outer tube (dO) are estimated as 1.6 nm and 2.2 nm, respectively, from Raman spectroscopy. Here, t is the wall thickness attributed to each nanotube, assumed to be 0.33 nm, equal to the spacing between graphene layers. In addition, Graphite ρ is the density of the graphite, which i...

The influence of internal tubes present in the fluidized bed on its hydrodynamic behavior was examined in this study. One tube was completely immersed in the bed of 650 m glass beads at 10 cm above the air distributor in the 15 cm inner diameter fluidized bed column of aspect ratio 1. The pressure fluctuations signal was collected over 300 s and was consequently analyzed by the both statistical...

Resistance to blood flow through peripheral vascular beds strongly influences cardiovascular function and transport to tissue. For a given vascular architecture, flow resistance is determined by the rheological behavior of blood flowing through microvessels. A new approach for calculating the contribution of blood rheology to microvascular flow resistance is presented. Morphology (diameter and ...

The creation of drag-reducing surfaces in deformed tubes is vital importance to thermal management, energy, and environmental applications. However, it remains a great challenge tailor the surface structure wettability inside slim complicated feature. Here, we describe an electrochemical anodization strategy achieve uniform superhydrophobic coating TiO2 nanotube arrays throughout inner deformed...