scholarly journals Flow control in microfluidics devices: electro-osmotic Couette flow with joule heating effect

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
C. Ahamed Saleel ◽  
Saad Ayed Alshahrani ◽  
Asif Afzal ◽  
Maughal Ahmed Ali Baig ◽  
Sarfaraz Kamangar ◽  
...  

PurposeJoule heating effect is a pervasive phenomenon in electro-osmotic flow because of the applied electric field and fluid electrical resistivity across the microchannels. Its effect in electro-osmotic flow field is an important mechanism to control the flow inside the microchannels and it includes numerous applications.Design/methodology/approachThis research article details the numerical investigation on alterations in the profile of stream wise velocity of simple Couette-electroosmotic flow and pressure driven electro-osmotic Couette flow by the dynamic viscosity variations happened due to the Joule heating effect throughout the dielectric fluid usually observed in various microfluidic devices.FindingsThe advantages of the Joule heating effect are not only to control the velocity in microchannels but also to act as an active method to enhance the mixing efficiency. The results of numerical investigations reveal that the thermal field due to Joule heating effect causes considerable variation of dynamic viscosity across the microchannel to initiate a shear flow when EDL (Electrical Double Layer) thickness is increased and is being varied across the channel.Originality/valueThis research work suggest how joule heating can be used as en effective mechanism for flow control in microfluidic devices.

2019 ◽  
Vol 16 (1) ◽  
pp. 51-63 ◽  
Author(s):  
S.S. Ghadikolaei ◽  
Kh. Hosseinzadeh ◽  
D.D. Ganji

Purpose The purpose of this study is, mixed convection on magnetohydrodynamic (MHD) flow of Eyring–Powell nanofluid over a stretching cylindrical surface in the presence of thermal radiation, chemical reaction, heat generation and Joule heating effect is investigated and analyzed. The Brownian motion and thermophoresis phenomenon are used to model nanoparticles (Buongiorno’s model). Design/methodology/approach The numerical method is applied to solve the governing equations. Obtained results from the effects of different parameters changes on velocity, temperature and concentration profiles are reported as diagrams. Findings As a result, velocity profile has been reduced by increasing the Hartman number (magnetic field parameter) because of the existence of Lorentz force and increasing Eyring–Powell fluid parameter. In addition, the nanoparticle concentration profile has been reduced because of increase in chemical reaction parameter. At the end, the effects of different parameters on skin friction coefficient and local Nusselt number are investigated. Originality/value Eyring–Powell nanofluid and MHD have significant influence on flow profile.


2017 ◽  
Vol 101 ◽  
pp. 96-105 ◽  
Author(s):  
Hyun-Woo Jung ◽  
Seung-Jae Kim ◽  
Yun-Jae Kim ◽  
Jung-Yup Kim ◽  
Joo-Yul Lee ◽  
...  

2016 ◽  
Vol 78 (8-4) ◽  
Author(s):  
Ummikalsom Abidin ◽  
Jumril Yunas ◽  
Burhanuddin Yeop Majlis

Joule heating effect is substantial in an electromagnet system due to high density current from current-carrying conductor for high magnetic field generation. In Lab-on-chip (LoC) Magnetically Activated Cell Sorting (MACS) device, Joule heating effect generating high temperature and affecting the biological cells viability is investigated. The temperature rise of the integrated system was measured using resistance temperature detector, RTD Pt100. Three temperature rise conditions which are from the bare spiral-shaped magnet wire, the combination of magnet wire and on-chip magnetic core and combination of magnet wire, on-chip magnetic core and 150 mm polydimethylsiloxane (PDMS) layer have been investigated.  The combination of electromagnet of spiral-shaped magnet wire coil and on-chip magnetic core has reduced the temperature significantly which are, ~ 38 %  and ~ 26 % with magnet wire winding, N = 10 (IDC = 3.0 A, t = 210 s) and N = 20 (IDC = 2.5 A, t = 210 s) respectively. The reduced Joule heating effect is expected due to silicon chip of high thermal conductivity material enable fast heat dissipation to the surrounding.  Therefore, the integration of electromagnet system and on-chip magnetic core has the potential to be used as part of LoC MACS system provided the optimum operating conditions are determined


2020 ◽  
Vol 13 (5) ◽  
pp. 054004
Author(s):  
Jun Tae Jang ◽  
Geumho Ahn ◽  
Sung-Jin Choi ◽  
Dong Myong Kim ◽  
Hyungjin Kim ◽  
...  

Author(s):  
Bicheng Chen ◽  
Cemal Basaran

Heat generated from Joule heating is an important factor in several failure mechanisms in microelectronic packaging (e.g. thermomigration, electromigration and etc) and large amount of the heat causes severe heat dissipation problem. It is further exaggerated by the continuous marching towards miniaturization of microelectronics. The techniques of measuring the Joule heating effects at the microscopic scale are quite limited especially for the full field measurement. Infrared microscopic imaging has been reported to measure the heat radiation by the Joule heating in the microscopic scale. Moire´ interferometry with phase shifting is a highly sensitive and a high resolution method to measure the in-plane full field strain. In this paper, it is demonstrated that the Joule heating effect can be measured by Moire´ interferometry with phase shifting at the microscopic scale. The copper sheet is used for the demonstration because of isotropic material property and well known thermal properties and parameters. The specimen was designed to minimize the out-of-plane strain and the strain caused by the thermal-structural effects. A finite element model was developed to verify the design of the structure of the specimen and the specimen was tested under different current density (input current from 0 to 24 A). Based on the research, a correlation relationship between the current density and the strain in two orthogonal directions (one in the direction of the current flow) was determined. The regression coefficients of the full field were analyzed. The experiment demonstrates the capability of measuring microscopic Joule heating effects by using Moire´ interferometry with phase shifting. The method can be further applied to the measurement of Joule heating effect in the microscopic solid structures in the electronic packaging devices.


Author(s):  
Moran Bercovici ◽  
Federico Paratore ◽  
Evgeniy Boyko ◽  
Govind V. Kaigala ◽  
Amir Gat

Sign in / Sign up

Export Citation Format

Share Document