... the formation of splash fingers. Solidification plays a major role in detracting the role of surface micro-obstructions, i.e., surface roughness, in splashing phenomena. 1 Corresponding author. e-mail:  aleksandra.nastic@utoronto.ca 2 Corresponding author. e-mail:  mostag@mie.utoronto.ca 15...

...Indrasis Mitra; Indranil Ghosh The effect of surface roughness on the thermohydraulics in minichannels has been studied numerically. Fluid flow (at low Reynolds number) through a typical three-dimensional (3D) channel subjected to constant heat flux (at the bottom) is analyzed incorporating surface...

... = electrical current (A) K f = thermal conductivity of air at film temperature (W/(m K)) l = length of the wire (m) Nu = Nusselt number R w = wire resistance at room temperature (Ω) Ra = average surface roughness (m) Re = Reynolds number...

... devices. (3) Previous analytical results were used to predict experimental data. The CHFs for pool boiling determined by Zuber [ 1 ] and that for pool boiling enhanced with the EHD force determined by Kano [ 19 ] were used to successfully predict the experimental results. (4) The surface roughness...

... heat flux, ultrasonic frequency, and pressure amplitude. The present results clearly bring out an interactive effect of these operating parameters with surface parameter like surface roughness. A mechanistic model unifying all these parameters has been presented to explain quantitatively the physics...

... mixing. With the flow marching in a more intense spiral pattern, a 40% improvement of heat transfer enhancement over the circular scale-roughened channels is observed. rectangular channel elliptic scale surface roughness heat transfer enhancement volume averaging theory VAT CFD turbulence...

... fractal surface roughness laminar flow microchannel When the characteristic length scale of a system is down to micrometers, the dynamics of microfluidics is crucially affected by the interaction of the fluid with the confining solid surface owing to large surface-to-volume ratio...

..., 67.2 °C, and 80.2 °C. At each pressure, jet impingement boiling at varying Reynolds numbers are characterized and compared with pool boiling heat transfer. The effect of surface roughness and fluid subcooling is studied at the lowest pressure of 0.176 bar. Boiling curves indicate a strong dependence...

... angle drops heat transfer hydrophobicity steam surface roughness wetting 18 05 2010 23 08 2011 09 12 2011 09 12 2011 2012 American Society of Mechanical Engineers ...

... trend has been observed with variation in the surface roughness of the heater as well. 12 09 2009 28 08 2010 31 08 2011 31 08 2011 boiling copper evaporation heat transfer nanoparticles nucleation sorption surface roughness suspensions thermal conductivity two-phase...

...Jae Bong Lee; Seong Hyuk Lee; Chang Kyoung Choi aluminium contact angle drops flow visualisation high-speed optical techniques hole density hydrophobicity impact (mechanical) microfluidics milling machines surface energy surface roughness surface texture water wetting 27...

...A. F. Emery; H. Dillon; A. M. Mescher The nominally one-dimensional conduction of heat through a slab becomes two dimensional when one of the surfaces is rough or when the boundary conditions are spatially nonuniform. This paper develops the stochastic equations for a slab whose surface roughness...

...Benjamin J. Jones; John P. McHale; Suresh V. Garimella The effect of surface roughness on pool boiling heat transfer is experimentally explored over a wide range of roughness values in water and Fluorinert ™ FC-77, two fluids with different thermal properties and wetting characteristics. The test...

... are acquired. The above data are obtained using commercial seamless stainless steel tube heater with an outer diameter of 9.0 mm and an average surface roughness of 1.09 μ m . The experimental results concluded that (i) critical heat flux (CHF) obtained in water with surfactant nanofluids gives nearly one...

... on the surface roughness level and yields lower surface superheat in the cooling-down mode, compared with the heating-up mode, at a given heat flux. Microstructured surface with protrusions was further tested using two approaches to gain better understanding on hysteresis. Data indicated that microstructured...

... smooth minichannels. Surface roughness effects on the liquid-vapor flow are discussed. In this respect, the friction factor in the proposed model is modified, in order to take into consideration also effects due to wall roughness. 14 04 2008 29 08 2008 21 01 2009 Surface roughness...

...Robert L. Jackson; Sushil H. Bhavnani; Timothy P. Ferguson A new multiscale model of thermal contact resistance (TCR) between real rough surfaces is presented, which builds on Archard’s multiscale description of surface roughness. The objective of this work is to construct the new model and use...

... predictions of the peak values of the Reynolds shear stress and Reynolds heat flux and their locations in the intermediate layer are well supported by the experimental and direct numerical simulation (DNS) data. The inflectional surface roughness data in a turbulent channel flow provide strong support to our...

.... There are several other functions besides the normal distribution function that can describe the characteristics of surface roughness ( 18 ). It is noted that Eq. 1 does not contain the correlation distance, but in a real surface the height at any position in the rough surface is correlated with the heights...

... of the Reynolds analogy factor (i.e., 2 St / c f ) with Reynolds number, freestream pressure gradient, surface roughness, and freestream turbulence. While the factor is fairly independent of Reynolds number, it increases with positive (adverse) pressure gradient and decreases with negative (favorable) pressure...