On the Surface Effects of Nanofluids in Cooling-System Materials

2013 ◽  
Vol 1558 ◽  
Author(s):  
Gustavo J. Molina ◽  
Valentin Soloiu ◽  
Mosfequr Rahman
Keyword(s):  
Ethylene Glycol ◽  
Cooling System ◽  
Nanoparticle Deposition ◽  
Testing Conditions ◽  
Wall Materials ◽  
Aluminum Surfaces ◽  
Nano Size ◽  
Size Powder ◽  
Roughness Measurements ◽  
Surface Changes

ABSTRACTNanofluids are nano-size-powder suspensions in liquids that are of interest for their enhanced thermal transport properties. They are studied as promising alternatives as compared to ordinary cooling fluids, but the effects of nanofluids on wall materials are largely unknown. The authors developed an instrument that uses a low-speed jet on material targets to test such effects.The work is presented of the authors’ experimental research on the early interactions of selected nanofluids (2% weight of alumina nanopowders in distilled water, and in solutions of ethylene glycol in water) with aluminum and copper samples as typical cooling-system materials. The observed surface changes (and possible nanoparticle deposition) for test periods as long as 14 hours were assessed by roughness and volumetric-removal wear measurements, and by microscope studies. Comparative roughness measurements indicate that alumina nanofluids in water and ethylene glycol solutions can start surface changes on aluminum surfaces, but show no effects on copper for the same testing conditions. These investigations set a baseline for further research and provide a suitable method for the testing of nanofluids effects in cooling system-materials.

scholarly journals Jet-Impingement Effects of Alumina-Nanofluid on Aluminum and Copper

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Gustavo J. Molina ◽  
Fnu Aktaruzzaman ◽  
Whitney Stregles ◽  
Valentin Soloiu ◽  
Mosfequr Rahman
Keyword(s):  
Ethylene Glycol ◽  
Base Fluid ◽  
Cooling System ◽  
Jet Impingement ◽  
Surface Modifications ◽  
Optical Microscope ◽  
Cooling Fluid ◽  
Nanosize Powder ◽  
Alumina Nanofluid ◽  
Surface Changes

Nanofluids are nanosize-powder suspensions that are of interest for their enhanced thermal transport properties. They are studied as promising alternatives to ordinary cooling fluids, but the tribiological effects of nanofluids on cooling-system materials are largely unknown. The authors have developed methodology that uses jet impingement on typical cooling-system materials to test such effects. The work is presented of the authors’ research on the interactions of a typical nanofluid (2% volume of alumina nanopowders in a solution of ethylene glycol in water) which is impinged on aluminum and copper specimens for tests as long as 112 hours. The surface changes were assessed by roughness measurements and optical-microscope studies. Comparative roughness indicate that both the reference cooling fluid of ethylene glycol and water and its nanofluid with 2% alumina produce roughness changes in aluminum (even for the shortest 3-hour test), but no significant roughness differences were observed between them. No significant roughness changes were observed for copper. Microscopy observations, however, show different surface modifications in both aluminum and copper by both the nanofluid and its base fluid. The possible mechanisms of early erosion are discussed. These investigations demonstrate suitable methods for the testing of nanofluid effects on cooling system-materials.

scholarly journals KRISTALISASI AMMONIUM PERKLORAT (AP) DENGAN SISTEM PENDINGINAN TERKONTROL UNTUK MENGHASILKAN KRISTAL BERBENTUK BULAT

2012 ◽  
Vol 9 (2) ◽  
Author(s):  
Anita Pinalia
Keyword(s):  
Ethylene Glycol ◽  
Ammonium Perchlorate ◽  
Crystal Size ◽  
Crystallization Process ◽  
Cooling System ◽  
Solid Particles ◽  
Crystal Shape ◽  
Controlled Cooling ◽  
Slow Cooling ◽  
Two Stages

AP is the solid particles with the largest composition in compossite propellant, with fractions 60-80%. Rounded particles of AP indirectly gives better performance of propellant. Therefore we need experiment the crystallization process to produce rounded AP crystal. In this experiment, crystallization was conducted by using a controlled cooling system. Cooling is done through two stages and using a different coolant. The first stage of slow cooling using water (30°C), and continued rapid cooling with ethylene glycol (-27°C). These experiment generate 45.45 kg AP with a purity 99.67%, 40 mesh crystal size, crystal shape close to round, yield 39.71%. Keywords: Ammonium perchlorate, Crystallization, Rounded crystal

Development and Assessment of a New Flow-Through Test Instrument to Study Wear and Erosion Effects of Nanofluids

2017 ◽  
Vol 5 (1) ◽  
pp. 58-74 ◽  
Author(s):  
Gustavo J. Molina ◽  
Fnu Aktaruzzaman ◽  
Valentin Soloiu ◽  
Mosfequr Rahman ◽  
Kenshantis Martin
Keyword(s):  
Cooling System ◽  
Surface Modifications ◽  
Copper Surface ◽  
Test Instrument ◽  
Simultaneous Testing ◽  
Flow Through ◽  
Technical Interest ◽  
Alumina Nanopowder ◽  
Nano Size ◽  
Reasonable Test

Nanofluids, the suspensions of nano-size powders in ordinary fluids, are of technical interest for their enhanced cooling properties, but their possible erosion-corrosion effects on cooling-system materials are mostly unknown. This paper discusses the rationale for designing and developing a new test-rig with flow-through parallel to the tested surfaces. The instrument conduct-chamber accommodates multiple specimens for simultaneous testing, and controlled fluid speed and temperature. This study shows that the new rig yields measurable surface-modifications from nanofluid action in reasonable test-times. Results are presented for a nanofluid (of 2%-alumina-nanopowder in water) that is recirculated in parallel-flow contact with polished aluminum and copper. Surface modifications are assessed by roughness, weighing of removed-material, and optical-microscopy, and results indicate that nanopowders can lead to patterns of wear, erosion and corrosion that are substantially different than those typically obtained from the base-fluids.

scholarly journals Multi-Response Optimization of Nanofluid-Based I. C. Engine Cooling System Using Fuzzy PIV Method

Processes ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 30 ◽  
Author(s):  
Mohd Seraj ◽  
Syed Mohd Yahya ◽  
Irfan Anjum Badruddin ◽  
Ali E. Anqi ◽  
Mohammad Asjad ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Cooling System ◽  
Heat Extraction ◽  
Inlet Temperature ◽  
Al2o3 Nanoparticles ◽  
Engine Cooling ◽  
Input Parameters ◽  
Improved Performance ◽  
Low Efficiency ◽  
Index Value

Effective cooling of the internal combustion (I. C.) engines is of utmost importance for their improved performance. Automotive heat exchangers used as radiator with low efficiency in the industry may pose a serious threat to the engines. Thus, thermal scientists and engineers are always looking for modern methods to boost the heat extraction from the engine. A novel idea of using nanofluids for engine cooling has been in the news for some time now, as they have huge potential because of better thermal properties, strength, compactness, etc. Nanofluids are expected to replace the conventional fluids such as ethylene glycol, propylene glycol, water etc. due to performance and environmental concerns. Overall performance of the engine cooling system depends on several input parameters and therefore they need to be optimised to achieve an optimum performance. This study is focussed on developing a nanofluid engine cooling system (NFECS) where Al2O3 nanoparticles mixed with ethylene glycol (EG) and water is used as nanofluid. Furthermore, it also explores the effect of four important input parameters of the NFECS i.e., nanofluid inlet temperature, engine load, nanofluid flow rate, and nanoparticle concentration on its five attributes (output responses) viz thermal conductivity of the nanofluid, heat transfer coefficient, viscosity of the nanofluid, engine pumping power required to pump the desired amount of the nanofluid, and stability of the nanofluid. Taguchi’s L18 orthogonal array is used as the design of experiment to collect experimental data. Weighting factors are determined for output responses using the Triangular fuzzy numbers (TFN) and optimal setting of the input parameters is obtained using a novel fuzzy proximity index value (FPIV) method.

On the Mechanism of Cathodic Protection

CORROSION ◽  
1985 ◽  
Vol 41 (10) ◽  
pp. 598-607 ◽  
Author(s):  
S. C. Dexter ◽  
L. N. Moettus ◽  
K. E. Lucas
Keyword(s):  
Weight Loss ◽  
Cathodic Protection ◽  
Cathodic Polarization ◽  
Color Pattern ◽  
Polarization Curves ◽  
Aluminum Surfaces ◽  
Surface Changes

Abstract Changes in the distribution of anodic sites on steel and aluminum surfaces have been monitored by applying a pH-indicating dye and observing how the color pattern on the surface changes as cathodic protection is applied. In addition, cathodic polarization curves for steel in seawater have been correlated with 120-day weight loss measurements and surface morphological observations for specimens receiving various levels of cathodic protection. The results are discussed in terms of the Mears and Brown, Hoar, and LaQue theories of cathodic protection and their implications as to the criteria for cathodic protection and the consequences of underprotection.

Coefficient of Performance of Thermoelectric Cooling on Nanofluids

2013 ◽  
Vol 459 ◽  
pp. 91-99
Author(s):  
Somchai Maneewan ◽  
Atthakorn Thongtha ◽  
Chantana Punlek
Keyword(s):  
Heat Exchanger ◽  
Ethylene Glycol ◽  
Heat Sink ◽  
Cooling System ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Cold Side ◽  
Input Condition ◽  
Current Input ◽  
Experimental Comparisons

This paper reports on experimental comparisons of coefficient of performance (COP) of a thermoelectric coolingsystem which cooled the hot side of the TEC by water (wc), ethylene glycol (egc) and nanofluids (nfc) The nanofluids is composed of ethylene glycol with silver nano(35 nm).The TEC was composed of the TE cooling modules, heat exchanger, and the air cooled heat sink at the cold side of the TE modules.Experiments were conducted with various current input 1 - 4.5 A to find out the optimum current input condition. To consideration of cooling capacity and COP of system was measured the hot and cold side temperature of TEC. Results shown that, the cooling capacity was increased with current input. The maximum cooling capacity of nfc, egc and wc are about 72, 62 and 41 W, respectively. Considered with highest COP found that the optimum current input is approximately 2.5 A. The maximum COP of nfc, egc and wc are about 2.01, 1.7 and 1.12, respectively. Therefore, the proposed TEC-nfc concept is expected to contribute to wider applications of the TE cooling system.

Magnesium Doped Hydroxyapatite through Mechanochemical Synthesis

2015 ◽  
Vol 1087 ◽  
pp. 329-333
Author(s):  
Sharifah Adzila ◽  
S. Ramesh ◽  
I. Sopyan ◽  
Mohd Hamdi Abdul Shukor
Keyword(s):  
Mechanochemical Synthesis ◽  
Present Method ◽  
Synthesis Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Properties ◽  
Nano Size ◽  
Size Powder ◽  
Mg Doped

The mechanochemical synthesis method was employed to synthesis hydroxyapatite (HA) and magnesium (Mg) doped hydroxyapatite (HA) powders. The effects of Mg2+ into the synthesized HA powder properties were investigated. Characterization of the synthesized HA (Mg-free HA) and Mg–doped HA at various concentrations (1% - 9% MgHA) were accomplished through X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analyses. The nano size powder of HA and Mg-doped HA were successfully synthesized through the present method and the influenced of Mg2+ in the HA was also indicated by the different peaks intensity and the crystal sizes obtained.

scholarly journals Analysis of Ethylene Glycol (EG)-based ((Cu-Al2O3), (Cu-TiO2), (TiO2-Al2O3)) Hybrid Nanofluids for Optimal Car Radiator Coolant

2020 ◽  
pp. 34-50
Author(s):  
J. A. Okello ◽  
W. N. Mutuku ◽  
A. O. Oyem
Keyword(s):  
Differential Equations ◽  
Ethylene Glycol ◽  
Waste Heat ◽  
Cooling System ◽  
Integration Scheme ◽  
Shooting Technique ◽  
Linear Ordinary Differential Equations ◽  
Linear Partial Differential Equations ◽  
Non Linear ◽  
Hybrid Nanofluids

Coolants are vital in any automotive since they manage the heat in the internal combustion of the engines by preventing corrosion in the cooling system as well as assist in eradicating the engine’s waste heat. This paper examines three different types of ethylene glycol-based hybrid nanofluids ((Cu-Al2O3), (Cu-TiO2), (TiO2-Al2O3)) to establish their cooling capabilities for industrial cooling applications. The vertical flow of these hybrid nanofluids combination through a semi-infinite convectively heated flat plate mimicking the flow of coolant in car radiator is modeled. The governing non-linear partial differential equations of fluid flow are transformed into a system of coupled non-linear ordinary differential equations using a suitable similarity transformation variables and the numerical solution executed using the shooting technique together with the fourth-order Runge-Kutta-Fehlberg integration scheme. The numerical simulation is executed using MATLAB and results are displayed graphically. The effects of pertinent parameters on velocity, temperature, skin friction, and local Nusselt number are investigated. From the study (Cu-Al2O3  hybrid nanocoolant leads to a rapid decrease in temperature at the boundary layer.

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