scholarly journals Fracture Retro Estimation of Friction Plate Made of 30CrMnSiA in Laboratory Condition

2020 ◽  
Vol 1653 ◽  
pp. 012061
Author(s):  
Zheng Hu ◽  
Xingyu Gao ◽  
Wanhao Zhang ◽  
Weifang Zhang ◽  
Xuerong Liu
2011 ◽  
Vol 301-303 ◽  
pp. 1560-1567 ◽  
Author(s):  
Man Chen ◽  
Biao Ma

The paper analyzes the failure mechanism of the wet shifting clutch, and puts forward the concept that the deformation of the clutch friction plate leads to the irregular collision between the driving and driven sides of disengaged clutch and accordingly forms the transient pulse signal; the short-time Fourier analysis on the vibration signals of failed clutch obtained via test proves such concept. The transient pulse signal in the relatively strong background signal is clearly extracted through the wavelet decomposition after zero setting, and an efficient wet shifting clutch fault diagnosis method is hereby formed.


Author(s):  
Yaguang Wu ◽  
Yu Fan ◽  
Lin Li ◽  
Zhimei Zhao

Abstract This paper proposes a flexible dry friction plate to mitigate the vibration of thin-walled structures for one resonance crossing. Based on a cantilever beam-friction damper finite element model, the geometry and material parameters of the friction plate are optimized numerically through steady-state response analyses by the widely-used Multi-Harmonic Balance Method (MHBM). In order to further improve the damping effect, piezoelectric material is distributed to the flexible damper, and two types of dry friction and piezoelectric hybrid dampers are explored, namely semi-active and passive, respectively. For semi-active hybrid dampers, piezoelectric material is used as an actuator to adjust the normal load applied to the friction interface in real time, so that the friction damping is improved. For passive ones, piezoelectric material is used as a transducer, which dissipates the strain energy stored in the wavy plate by the shunting circuit, additional shunted piezoelectric damping contributes to the total output damping accordingly. Better damping effect compared with the friction baseline is realized for the two types ideally. This damping module has a simple structure and avoids the problem of installation and maintenance of piezoelectric material which is generally bonded to the host structure. Technical challenges are: the semi-active type requires excessive voltage applied to the piezoelectric actuator, while the passive one needs to connect a programmable synthetic circuit.


2019 ◽  
Vol 28 (2) ◽  
pp. 167-176
Author(s):  
Mohammad Shamimul Alam ◽  
Md Nazmul Hoque ◽  
Mousumi Akter ◽  
Reza Md Shahjahan

Samples of Drosophila species were collected from some selected sites (viz., Dohar Upazila of Dhaka Division, Hironpoint of the Sundarbans, Satchori of Sylhet Division) of Bangladesh and these were cultured in the laboratory to study developmental stages, external morphological traits and sex comb. They were identified as D. melanogaster, D. ananassae and D. bipectinata. The sex comb teeth number and arrangement were distinct for all three species. D. melanogaster had one row of 10 - 11 teeth in the sex comb. D. ananassae had eight rows of teeth in the sex comb possessing 32 - 33 teeth in total. D. bipectinata had 2 - 3 rows of teeth in the sex comb and total teeth number varied from 11 to 15. Among three species, sex comb teeth number of D. bipectinata varied most. Eleven different patterns (n=20) in sex comb were observed in D. bipectinata indicating significant diversity within species. Variation in pupation sites among three species was also observed in the laboratory condition. D. bipectinata pupated on the food medium, whereas other two species pupated on the vial wall. Thus, diversity among these three species of Drosophila was documented which could be utilized as bioindicator in future. Dhaka Univ. J. Biol. Sci. 28(2): 167-176, 2019 (July)


Author(s):  
Muh. Herjayanto ◽  
Annisa Misykah Mauliddina ◽  
Esa Rama Widiyawan ◽  
Nugroho Agung Prasetyo ◽  
Lukman Anugrah Agung ◽  
...  

Oryzias sp. from Tunda Island, Indonesia has the potential as a model organism in laboratories and also ornamental fish. Basic information regarding maintenance during adaptation post-transportation from its habitat in nature, embryo incubation and maintenance of larvae is needed as a basis for breeding activities. The results showed that Oryzias sp. from Tunda Island can adapt, spawning and produce a total 262 eggs (diameter 0.88-1.02 mm) in a controlled environment. Eggs from spawning in nature begin to hatch on the 11th incubation day, the hatching peak occurs on the 13th day with a hatching process 4-9 days at 25-27oC. The hatching rate ranges from 57.14-100% and the survival of 5 days old lavae after hatching is 72.72-100.00%. The transportation technique in this study has not been able to suppress fish mortality during post-transportation rearing.    


2019 ◽  
Vol 35 (2) ◽  
Author(s):  
Aqsa Khan ◽  
Sabyan Faris Honey ◽  
Bajwa Babar ◽  
Nelofer Jamil ◽  
Muhammad Sohail Mazhar

Sign in / Sign up

Export Citation Format

Share Document