Mapping of power consumption and friction reduction in piezoelectrically-assisted ultrasonic lubrication

2015 ◽  
Author(s):  
Sheng Dong ◽  
Marcelo J. Dapino
Author(s):  
Sheng Dong ◽  
Marcelo J. Dapino

Ultrasonic vibration has been proven effective in reducing dynamic friction when superimposed onto the macroscopic relative velocity between two surfaces. This phenomenon is often referred to as ultrasonic lubrication. Piezoelectric materials can be employed to generate ultrasonic vibration. Typically, solid or fluid lubricants are employed to mitigate wear. However, in applications such as aerospace systems, which operate in particularly harsh environments, traditional lubrication methods are not always applicable. This paper investigates the relationship between friction force reduction and wear reduction in ultrasonically lubricated surfaces. A pin-on-disc tribometer is modified through the addition of a piezoelectric transducer which vibrates the contact between pin and disc. A piezo-actuator is installed to generate 22 kHz vibration in the direction perpendicular to the disc. Three different linear speeds are employed by changing rotation speeds of the disc and running time. Friction and wear metrics such as volume loss, surface roughness, friction forces and stick-slip effects are compared before and after application of ultrasonic vibration. Relationships between linear speed and friction reduction, stick-slip reduction, and wear reduction are analyzed.


2020 ◽  
Author(s):  
SMITA GAJANAN NAIK ◽  
Mohammad Hussain Kasim Rabinal

Electrical memory switching effect has received a great interest to develop emerging memory technology such as memristors. The high density, fast response, multi-bit storage and low power consumption are their...


2020 ◽  
Vol 64 (1-4) ◽  
pp. 165-172
Author(s):  
Dongge Deng ◽  
Mingzhi Zhu ◽  
Qiang Shu ◽  
Baoxu Wang ◽  
Fei Yang

It is necessary to develop a high homogeneous, low power consumption, high frequency and small-size shim coil for high precision and low-cost atomic spin gyroscope (ASG). To provide the shim coil, a multi-objective optimization design method is proposed. All structural parameters including the wire diameter are optimized. In addition to the homogeneity, the size of optimized coil, especially the axial position and winding number, is restricted to develop the small-size shim coil with low power consumption. The 0-1 linear programming is adopted in the optimal model to conveniently describe winding distributions. The branch and bound algorithm is used to solve this model. Theoretical optimization results show that the homogeneity of the optimized shim coil is several orders of magnitudes better than the same-size solenoid. A simulation experiment is also conducted. Experimental results show that optimization results are verified, and power consumption of the optimized coil is about half of the solenoid when providing the same uniform magnetic field. This indicates that the proposed optimal method is feasible to develop shim coil for ASG.


2020 ◽  
pp. 57-62
Author(s):  
Olga Yu. Kovalenko ◽  
Yulia A. Zhuravlyova

This work contains analysis of characteristics of automobile lamps by Philips, KOITO, ETI flip chip LEDs, Osram, General Electric (GE), Gtinthebox, OSLAMPledbulbs with H1, H4, H7, H11 caps: luminous flux, luminous efficacy, correlated colour temperature. Characteristics of the studied samples are analysed before the operation of the lamps. The analysis of the calculation results allows us to make a conclusion that the values of correlated colour temperature of halogen lamps are close to the parameters declared by manufacturers. The analysis of the study results has shown that, based on actual values of correlated colour temperature, it is not advisable to use LED lamps in unfavourable weather conditions (such as rain, fog, snow). The results of the study demonstrate that there is a slight dispersion of actual values of luminous flux of halogen lamps by different manufacturers. Maximum variation between values of luminous flux of different lamps does not exceed 14 %. The analysis of the measurement results has shown that actual values of luminous flux of all halogen lamps comply with the mandatory rules specified in the UN/ECE Regulation No. 37 and luminous flux of LED lamps exceeds maximum allowable value by more than 8 %. Luminous efficacy of LED lamps is higher than that of halogen lamps: more than 82 lm/W and lower power consumption. The results of the measurements have shown that power consumption of a LED automobile lamp is lower than that of similar halogen lamps by 3 times and their luminous efficacy is higher by 5 times.


2014 ◽  
pp. 192-196
Author(s):  
A. Drozd ◽  
◽  
S. Mileiko ◽  
V. Kalinichenko ◽  
N. Ulchenko
Keyword(s):  

2016 ◽  
Vol 136 (11) ◽  
pp. 1555-1566 ◽  
Author(s):  
Jun Fujiwara ◽  
Hiroshi Harada ◽  
Takuya Kawata ◽  
Kentaro Sakamoto ◽  
Sota Tsuchiya ◽  
...  

Author(s):  
Yuri Kolev ◽  
Атanas Atanasov ◽  
Таnia Pehlivanova

A load profile measuring device takes information about the power consumption without modification of the power lines. Using current transformers, the current is measured in each of the phases and the active power consumed by the user is determined. The developed software for it allows for simultaneous recording at different user selectable timing intervals. The device is designed and tested in two facilities - a School and a Farm.


2012 ◽  
Vol E95.B (8) ◽  
pp. 2538-2548
Author(s):  
Yukio OGAWA ◽  
Go HASEGAWA ◽  
Masayuki MURATA

2014 ◽  
Vol E97.B (12) ◽  
pp. 2698-2705
Author(s):  
Tomoyuki HINO ◽  
Hitoshi TAKESHITA ◽  
Kiyo ISHII ◽  
Junya KURUMIDA ◽  
Shu NAMIKI ◽  
...  

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