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Suppression of Oscillation of a Certain Two-Mass System with the Help of the Generalized Gauss Principle
Kamilla Maratovna Fazlyeva,
Timofei Sergeevich Shugailo,
Mikhail Petrovich Yushkov
Issue:
Volume 5, Issue 3, June 2017
Pages:
129-135
Received:
10 May 2017
Published:
10 May 2017
Abstract: The paper studies the suppression of oscillation of a certain two-mass system when it is transferred from the initial state of rest to the given state of rest during a time interval prescribed. The problem is solved by the two methods: the Pontryagin maximum principle (first method) and the generalized Gauss principle (second method). Computational results are presented and the solutions are compared to each other. When the time of motion is short the both methods give practically the same results, but when the time of motion is long the results differ widely. If the time of motion is long then the second method is more preferable than the first one, since the control obtained by the second method sways the mechanical system less than the control obtained by the classical approach. This can be explained by the fact that the first method contains the control including harmonics with the natural frequency of the system, and this seeks to put the system into resonance. In contrast to this, in the second method the control is sought in the form of time polynomial that provides relatively smooth motion of the system. It is noted that the first method always finds the control with jumps at the beginning and at the end of motion. The second method also gives the same jumps when the time of motion is short, but when the time of motion is long the similar jumps vanish when one uses the generalized Gauss principle.
Abstract: The paper studies the suppression of oscillation of a certain two-mass system when it is transferred from the initial state of rest to the given state of rest during a time interval prescribed. The problem is solved by the two methods: the Pontryagin maximum principle (first method) and the generalized Gauss principle (second method). Computational...
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Mathematical Modeling for Material Removal and Optimization of Ultrasonic Drilling of Polycarbonate and Acrylic Glass for Surface Roughness by GRA Approach
Kanwal Jeet Singh,
Inderpreet Singh Ahuja,
Jatinder Kapoor
Issue:
Volume 5, Issue 3, June 2017
Pages:
136-154
Received:
18 March 2017
Accepted:
6 April 2017
Published:
17 May 2017
Abstract: Polycarbonate bullet proof and acrylic heat resistant glasses are used as the functional material in many industrial application. In automobile industries, banks and cabins, polycarbonate bullet proof glass has been used for security purpose. Similarly, acrylic heat resistant glass is used in furnace, microwaves, space craft and airplane applications. In this experimental research paper, Taguchi modal and Grey relational analysis are utilized for the ultrasonic drilling in these materials. For experimentation, input parameters are concentration, abrasive, grit size, power rating, hydrofluoric acid and tool materials. Output parameters are material removal rate, tool wear rate and surface roughness. In which, surface roughness is most significant output parameter, because it describe accuracy of the process. Through optimization analysis, Taguchi modal suggest that 40% abrasive concentration, mixture of (Alumina, Silicon carbide and Boron carbide) abrasive in 1:1:1, 600 grit of abrasive and 1.5% hydrofluoric acid gives best results for drilling in polycarbonate bullet proof glass material. Similarly, in acrylic heat resistant glass, mixture of Silicon carbide and Boron carbide (1:1), 600 grit abrasive and 1% hydrofluoric acid gives the optimum results. Concentration of slurry, abrasive grit size and hydrofluoric acid are the most significant parameters for ultrasonic drilling in both materials. Through Grey relational analysis the surface roughness is improved by 40% and 48% in polycarbonate (UL-752) and acrylic (BS-476) glass respectively.
Abstract: Polycarbonate bullet proof and acrylic heat resistant glasses are used as the functional material in many industrial application. In automobile industries, banks and cabins, polycarbonate bullet proof glass has been used for security purpose. Similarly, acrylic heat resistant glass is used in furnace, microwaves, space craft and airplane applicatio...
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Optimization of Molding Sand Composition for Casting Al Alloy
Sumaiya Shahria,
Md. Tariquzzaman,
Md. Habibur Rahman,
Md. Al Amin,
Md. Abdur Rahman
Issue:
Volume 5, Issue 3, June 2017
Pages:
155-161
Received:
6 March 2017
Accepted:
5 April 2017
Published:
17 May 2017
Abstract: In the aluminum casting industry, the foundry manufacturers find the quality of the sand mold as important fact to achieve high quality aluminum castings. The aim of this research is to reduce aluminum casting defects by optimizing proportion of water and bentonite added to a recycled sand mold. Aluminum 356 alloy was preferred for this research based on the traditional method of trial and error twelve castings were performed with the different proportion of sand, bentonite, and water. A five scale rating method has been applied to rate the casted product upon number of defects. This research has been carried out by analyzing the variance (ANOVA) by using Minitab 17.0 software and finally concludes with the optimum level of composition for casting Al with the result of 90% sand, 5% bentonite, and 5% water.
Abstract: In the aluminum casting industry, the foundry manufacturers find the quality of the sand mold as important fact to achieve high quality aluminum castings. The aim of this research is to reduce aluminum casting defects by optimizing proportion of water and bentonite added to a recycled sand mold. Aluminum 356 alloy was preferred for this research ba...
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Non-newtonian Rabinowitsch Fluid Effects on the Lubrication Performances of Sine Film Thrust Bearings
Jaw-Ren Lin,
Hsiu-Lu Chiang,
Yu-Kang Chiu
Issue:
Volume 5, Issue 3, June 2017
Pages:
162-167
Received:
19 May 2017
Published:
20 May 2017
Abstract: Thrust bearings are generally developed to sustain axial load generated from rotating machinery. Predicting lubrication performances of thrust bearings plays an important role in engineering applications. Taking into account the effects of non-Newtonian rheology, the lubrication performances for a sine film thrust bearing are investigated in the present paper. By employing a small perturbation technique to the nonlinear non-Newtonian Reynolds equation, analytical solutions of the film pressure, the load-carrying capacity, the friction parameter and the required volume flow rate are derived. Comparing with the case lubricated with a Newtonian lubricant, the non-Newtonian Rabinowitsch fluids (including the pseudo-plastic fluids and the dilatant fluids) show significant influences on the lubrication performances of a sine film thrust bearing, especially for a larger value of the non-Newtonian parameter.
Abstract: Thrust bearings are generally developed to sustain axial load generated from rotating machinery. Predicting lubrication performances of thrust bearings plays an important role in engineering applications. Taking into account the effects of non-Newtonian rheology, the lubrication performances for a sine film thrust bearing are investigated in the pr...
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Design of Multi Hole Machining Equipment for Flange Parts Based on CAD/CAM
Shuangxi Jing,
Xiaoyu Yang,
Chenxu Luo,
Jinle Yuan,
Zhipeng Luo
Issue:
Volume 5, Issue 3, June 2017
Pages:
168-174
Received:
1 April 2017
Accepted:
13 April 2017
Published:
23 May 2017
Abstract: According to the situation of multi hole machining with linear circular flange flange parts, a device is analyzed and designed, which can process multiple flange holes at the same time, and the design of the device including fixture design and multi spindle box design. the three - dimensional modeling and analysis software is used, make a study on the design and manufacture of the flange hole of the 96 pipe sleeve, through the selection of hardware, such as drill bits, machine tools, gears, shafts, and the simulation of Ansysworkbench force of main parts, obtain the design device and the processing method suitable for mass production of linear round flange parts with seat. It also can achieve drilling, reaming and tapping function conversion by adjusting the speed and dril.
Abstract: According to the situation of multi hole machining with linear circular flange flange parts, a device is analyzed and designed, which can process multiple flange holes at the same time, and the design of the device including fixture design and multi spindle box design. the three - dimensional modeling and analysis software is used, make a study on ...
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Developing of Heating and Cooling Universal System Sourced by New Type of Heat Pump and Method for Its Design
Zohrab Melikyan,
Taron Movsesyan
Issue:
Volume 5, Issue 3, June 2017
Pages:
175-181
Received:
24 March 2017
Accepted:
22 April 2017
Published:
1 June 2017
Abstract: At present closed and open loop geothermal heat pumps are in use. Nevertheless, they have disadvantages, which seriously limit their wide use. First disadvantage is the shortage of rather large free areas for laying underground heat exchangers in form of rather long pipelines. This problem arises especially in towns and large cities. Second disadvantage is the rather expensive and often not affordable construction of heating and cooling systems, sourced by heat pumps. For overcoming mentioned disadvantages and increasing energy efficiency and cost effectiveness of heating and cooling systems a new structure of heat pump and method for its calculation and design are suggested. Because the developed heat pump is able round year efficiently satisfying thermal needs for different purposes of a house it is called “universal heat pump”.
Abstract: At present closed and open loop geothermal heat pumps are in use. Nevertheless, they have disadvantages, which seriously limit their wide use. First disadvantage is the shortage of rather large free areas for laying underground heat exchangers in form of rather long pipelines. This problem arises especially in towns and large cities. Second disadva...
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Preliminary Investigation on Production of Biogas from Domestic Sewage
Kwasi-Effah C. Collins,
Ebunilo O. Patrick,
Ogbeide O. Osarobo
Issue:
Volume 5, Issue 3, June 2017
Pages:
182-185
Received:
3 February 2017
Accepted:
5 May 2017
Published:
27 June 2017
Abstract: A domestic biogas digester was used to test the concept of controlled anaerobic digestion. A mixture of 20kg cow dong, 4kg of water hyacinth, and 8 kg of domestic waste, was used to run the test. Result showed that a reasonable amount of biogas is generated on the second day of the test period. However, during the 5th and 7th day of the 10 days test period, biogas production was at its peak. The design is simple and easy to use. This design is capable of enabling the layman grasp the function and theory behind each component of the design with only a small amount of guidance. The idea here is to encourage people looking at the design to think and understand the requirements of controlled anaerobic digestion and the continuous flow model.
Abstract: A domestic biogas digester was used to test the concept of controlled anaerobic digestion. A mixture of 20kg cow dong, 4kg of water hyacinth, and 8 kg of domestic waste, was used to run the test. Result showed that a reasonable amount of biogas is generated on the second day of the test period. However, during the 5th and 7th day of the 10 days tes...
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