Investigation of Forced Convective Heat Transfer in Nanofluids
Zain Fathy Abu Shaeer,
Mofreh Hamada Hamed
Issue:
Volume 4, Issue 1, June 2020
Pages:
1-6
Received:
6 August 2019
Accepted:
25 December 2019
Published:
16 January 2020
Abstract: The present paper concerns a theoretical study of heat transfer of the laminar two dimensional flows of various nanofluids taking into account the dissipation due to viscous term past a 2-D flat plate had a different temperatures. The steady incompressible flow equations were used and transformed to a nonlinear Ordinary Differential Equation (ODE) using a similarity variable. These equations were solved numerically using implicit finite difference method in which the partial derivatives were replaced by appropriate central differences patterns and using Newton’s method to linearize the resulting algebraic equations. Finally, the block-tridiagonal-elimination technique was used to solve that linear system. Three types of nanoparticles namely, Cu-water, Al2O3-water, and TiO2-water in the base flow of water were considered. The symbolic software Mathematica was used in the present study. Different types of nanoparticles, different values of, nanoparticle volume fraction, Eckart and Prandtl number were tested and analyzed at different wall temperature. The effect of these parameters on the flow behaviour, the local skin friction coefficient, Nusselt number, the velocity and the temperature profiles were presented and investigated. It is concluded that these parameters affect the fluid flow behaviour and heat transfer parameters especially nanoparticle concentration. The presence of nanoparticles showed an enhancement in the heat transfer rate moreover its type has a significant effect on heat transfer enhancement.
Abstract: The present paper concerns a theoretical study of heat transfer of the laminar two dimensional flows of various nanofluids taking into account the dissipation due to viscous term past a 2-D flat plate had a different temperatures. The steady incompressible flow equations were used and transformed to a nonlinear Ordinary Differential Equation (ODE) ...
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Sensor Nodes and System Proposal for Security and Environmental Data Collection in Developing Countries
Pierre Tsafack,
Valery Nkemeni,
Bruno Allard
Issue:
Volume 4, Issue 1, June 2020
Pages:
7-13
Received:
18 May 2020
Accepted:
10 June 2020
Published:
13 August 2020
Abstract: This paper consists of RF-based sensor nodes design for survey of critical areas and distance collection of useful environmental data such as pollutants, pluviometry, temperature and humidity. Given poor or nonexistent accesses in areas under investigation, adequate RF equipped sensor nodes are posted at indicated locations for collecting data to be processed by a microcontroller used as a control and processing unit. The processing unit also processes requests from users and sends feedbacks by SMS; those requests and related feedbacks are transmitted through a GSM module. Data from sensors are also processed and corresponding SMS alerts or calls are automatically sent when set parameters are detected. In addition to the use of GSM and microcontroller-based processing unit as in few systems, the proposed system here used RF-based sensor nodes for local area data sensing. That allows real time investigation of given locations. The prototype was successfully developed and tested with specific COTS components such as RF TX/RX433MHz for local area communication, PLL4046 for data formatting to digital, GSM SIM900 for long distance communication, and PIC16F877 microcontroller for data processing.
Abstract: This paper consists of RF-based sensor nodes design for survey of critical areas and distance collection of useful environmental data such as pollutants, pluviometry, temperature and humidity. Given poor or nonexistent accesses in areas under investigation, adequate RF equipped sensor nodes are posted at indicated locations for collecting data to b...
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