Hydraulic and thermal analysis of automatic transmission fluid in the presence of nano-particles and twisted tape: An experimental and numerical study

2021 ◽  
Vol 28 (11) ◽  
pp. 3404-3417
Author(s):  
Ali Qasemian ◽  
Faranak Moradi ◽  
Amin Karamati ◽  
Ali Keshavarz ◽  
Amin Shakeri
Author(s):  
C. Gnanavel ◽  
R. Saravanan ◽  
M. Chandrasekaran

The heat transfer enhancement is normally demanded in industries for heating, cooling and evaporation in the equipment’s like air conditioning, radiators and refrigerators etc. The passive, active or combination of them usually employed for intensification of heat transfer in such heat exchangers. In this study, we focus on an innovative passive technique. The dual approach is to increase the conductivity of the suspended nano-particles such as titanium dioxide, beryllium oxide or beryllia, zinc oxide and copper oxide in the water. The flow resistance is offered by inserting the twisted tape with trapezoidal cut. The objective of the numerical study is to investigate the thermal and flow fields by utilizing various types of nano-fluids with and without twisted tape in the double tube heat exchanger. The finite volume method is employed to solve the continuity, momentum and energy equations.


2019 ◽  
Vol 7 (SI-TeMIC18) ◽  
Author(s):  
Norhanifah Abdul Rahman ◽  
Matzaini Katon Katon ◽  
Nurina Alya Zulkifli Zulkifli

Automatic Transmission (AT) system is efficient in the aspects of vehicle safety, comfort, reliability and driving performance. The objectives of this paper are to collect the oil samples from AT systems of engine bus according to manufacturer's recommendations and analyse collected oil samples using oil analysis technique. The sample transmission fluid which was taken from the AT gearbox has been experimentally analyzed. The oil samples were taken with an interval of 5,000km, 30,000km, 50,000km, 80,000km, 180,000km and 300,000km for AT bus operation. These samples then have been analyzed by comparing between new and used transmission fluid using Fourier Transform Infrared (FTIR) spectroscopy. Oil analysis by FTIR is a form of Predictive Maintenance (PdM) to avoid major failure in machine elements. Most machine elements are not easily accessible in the transmission system. Having a reliable technique would avoid the needs to open the components unnecessarily, hence, help to prevent catastrophic failure which are very costly, and ease of regular monitoring. In order to identify the major failures of automatic gearbox, forecasts can be made regarding the lube transmission fluid analysis test. By using this test, the minor problems can be determined before they become major failures. At the end of this research, the wear particles profile for interval mileage of AT system was obtained. Keywords: Wear, Automatic Transmission (AT), Transmission fluid, Fourier Transform Infrared (FTIR), Oil analysis.


1998 ◽  
Vol 14 (4) ◽  
pp. 347-380 ◽  
Author(s):  
Roy Fewkes ◽  
David G. Hughes ◽  
Ivan E. Joseph ◽  
James L. Sumieski

Author(s):  
Leonardo I Farfan-Cabrera ◽  
Ezequiel A Gallardo-Hernández ◽  
José Pérez-González ◽  
Benjamín M Marín-Santibáñez ◽  
Roger Lewis ◽  
...  

In this work, an assessment of the performance of thermo-oxidated Jatropha oil as a lubricant for actual wet clutch materials was performed and compared with a commercial automatic transmission fluid. For this, Jatropha oil, a commercial automatic transmission fluid and a blend of 20 vol% Jatropha oil–80 vol% automatic transmission fluid were subjected to thermo-oxidative aging at 26 °C and 100 °C, followed by a pin-on-disk testing with disk samples from an actual wet clutch. Evaluation of the film thickness at the sliding interface resulted in a boundary lubrication regime for all the tests. The changes in oxidation, viscosity, and a viscosity index of the samples were evaluated along with friction coefficients at various sliding speeds. Jatropha oil was the most sensitive to thermo-oxidation. Jatropha oil and the blend showed a higher viscosity increase than automatic transmission fluid with thermo-oxidation, while the viscosity index of all oils was decreased considerably, Jatropha oil and the blend being the most reduced. Finally, the anti-shudder property, as measured by the change in the friction coefficient with a sliding speed, of Jatropha oil and automatic transmission fluid was improved by thermo-oxidation at 26 °C but worsened at 100 °C, meanwhile it was barely affected in the blend. Therefore, these results indicate that using pure Jatropha oil as automatic transmission fluid would be unsuitable, but blending it with automatic transmission fluids in specific proportions may be apposite for improving the friction properties of wet clutches even under thermo-oxidative conditions.


2017 ◽  
Vol 42 (38) ◽  
pp. 24319-24337 ◽  
Author(s):  
M. Ghasemi ◽  
A. Ramiar ◽  
A.A. Ranjbar ◽  
S.M. Rahgoshay

2011 ◽  
Vol 10 (01) ◽  
pp. 135-142
Author(s):  
CHUNMEI ZHANG ◽  
YONGFENG LI

Thermal analysis can be used as one of the basis for the friction pair material selection in high-speed friction braking system. In this study, the experimental results showed that surface temperature could be reduced by increasing the radius of the friction disk or thermal conductivity coefficient of disk material with stable braking; In the early stage of long braking, the temperature on the friction surface rises rapidly, but further braking does not lead to a significant rise in temperature; In the case of short braking, there is not enough time for the friction surface to reach the critical temperature, and the disk surface reaches the maximum temperature at the end of braking. During long braking, the dimensionless time capacity of the friction surface reaching the highest temperature is F0 ≈ 0.1F0s.


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