This paper presents the design, fabrication, and testing of passive plastic microfluidic valves and active injectors driven by capillary forces. The passive valves stop the flow of a liquid inside a capillary using a capillary pressure barrier that develops when the channel cross section changes abruptly. Two types of valves with vertical and horizontal neck regions were fabricated yielding pre...

The purpose of this study is to investigate the two-phase flow field characteristics in flat plate heat exchangers. The main objectives are the causes of plate wetting/drying, measurement of fluid flow field characteristics, and the effects of enhanced plate passageways. Three types of passageways are being investigated: smooth-walled passageways, chevron-style passageways, and embossed (bumpy)...

One of the important characteristics in predicting the flow of two phases (gas and liquid) in the industrial equipment is the gas percentage in the liquid, which is called voidage. This characteristic can be measured by different methods; the optical method is one of them. In the present work, a He-Ne laser light is employed to measure the voidage. The measurement depends on the principle of la...

"> In the present study, transesterification of soybean oil to Fatty Acid Methyl Ester (FAME) was carried out in the microreactor. The system performance was <span style="font-size: 9pt; color: #000000; ...

Flow within thick liquid films present owing to capillary effects in the pore space is of key importance in many multiphase flow applications in porous media, for example, drying or oil recovery processes. The viscous resistance to the flow is a key parameter for modelling fluid transport in such situations. It is well known for liquid films wetting the corners of tubes of polygonal cross-secti...

Dense arrays of aligned carbon nanotubes are designed into strips, nanowicks, as a miniature wicking element for liquid delivery and potential microfluidic chemical analysis devices. Liquid wicks away along the nanowicks spontaneously. This delivery function of nanowicks enables novel fluid transport devices to run without any power input, moving parts or external pump. Flow around the opaque n...