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Optimal design of Investment Casting system for a Stuffing Box with Pedestal of Centrifugal Pump: Computer Simulations and Experimental Verification

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Journal of the Chinese Society of Mechanical Engineers, Transactions of the Chinese Institute of Engineers, Series C/Chung-Kuo Chi Hsueh Kung Ch'eng Hsuebo Pao 2020年第5期41卷 551-563页

作者： Kuo, Jenn-Kun Huang, Pei-Hsing Tsai, Yu-Ting Zhong, Qi Chou, Chuen-Shii Department of Greenergy National University of Tainan Tainan70005 Taiwan Department of Mechanical Engineering National Yunlin University of Science and Technology Yunlin64002 Taiwan Bachelor's Program in Precision System Design Feng Chia University Taichung40724 Taiwan Department of Mechanical Engineering National Pintung University of Science and Technology Pingtung91201 Taiwan

The stuffing box with pedestal (SBP) is a major component in centrifugal pumps (CPs). It is responsible for the transfer of load generated in the CP to the baseplate of the pump and finally to the ground. SBPs are usually fabricated using investment casting;however, this process is prone to residual casting defects, which can reduce mechanical strength and increase the likelihood of crack formation following long-term usage. In this study, the AnyCasting numerical simulation software package was used to optimize the investment parameters for the casting of an SBP in SUS304 alloy. Optimization efforts targeted the shrinkage cavity (based on retained melt modulus) and porosity defects (based on Niyama criterion). The results of preliminary simulations and experiments informed the establishment of five casting schemes for subsequent simulation. We used virtual thermo-dynamic sensors to determine the rate and direction of solidification in the mold cavity, and also investigated variations in the velocity of the molten metal at the inlets of the gating system as a function of time. The optimal casting parameters derived in simulations were assessed by fabricating an SBP via investment casting in a domestic foundry. Nondestructive testing based on X-ray analysis revealed none of the detrimental defects commonly associated with this type of casting. © 2020, Chinese Mechanical Engineering Society. All right reserved.

关键词： Investment casting

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Online measurement of polymer melt viscosity in injection molding 75

Online measurement of polymer melt viscosity in injection mo...

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75th Annual Technical Conference and Exhibition of the Society of Plastics Engineers, SPE ANTEC Anaheim 2017

作者： Huang, Ming-Shyan Nian, Shih-Chih Chen, Jian-Yu Yang, Kai-Jye Tseng, Jian-Chou Dept. of Mechanical and Automation Engineering National Kaohsiung First University of Science and Technology Taiwan Dept. of Power Mechanical Engineering National Taitung College Taiwan Bachelor Program in Precision System Design Feng Chia University Taiwan

ISBN: (纸本)9780692883099

Melt viscosity, determined by the shear rate, barrel temperatures, and pressure during plasticization, greatly affects the flow ability of polymer melts as well as the quality of injection-molded parts. In particular, the consistency of molding qualities is highly relevant to the plasticizing quality at each cycle (i.e., injection molding requiring a high yield rate highly relies on the stability of polymer melts). However, numerous factors affect the plasticizing quality, including the geometry of injection screws, processed polymer materials, processing parameters of plasticization such as the feeding rate, screw rotational speed, barrel temperatures, back pressure, and screw backward speed. The conventional approach of plasticization in injection molding machines uses a single reciprocating screw for conveying, melting, and metering polymer melts. The plasticizing quality is roughly adjusted by indirectly controlling barrel temperatures;thus, the melt viscosity varies. An in-suit approach of assuring melt quality is to measure the melt viscosity variation online, which is a more suitable indicator of the plasticizing quality than temperature. This study thus monitored the melt viscosity variations in polymer melts by using in-mold pressure sensors. Furthermore, the effects of the injection velocity and mold temperature on the melt viscosity variations were examined.

关键词： Polymer melts

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Study on the Characteristics of Acoustic Radiation of Microspeaker Associated with Pattern of Diaphragm with Finite Element Method

Study on the Characteristics of Acoustic Radiation of Micros...

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2018 3rd International Conference on Computational Modeling, Simulation and Applied Mathematics (CMSAM 2018)

作者： Yu-Cheng Liu En-Tzu Chang Hung-Wei Chen Bachelor's Program in Precision System Design Feng Chia University Master's Program of Electro-Acoustics Feng Chia University

The objective of this study is to investigate the acoustic radiation of Microspeaker based on various pattern geometries of diaphragm. The influence of first resonant frequency(f) is discussed, as are the radiation efficiency(SPL) and impedance curve(IMP). First, microspeaker geometry was reconstructed with CAD software(Creo). Four geometric pattern parameters, width, angle, depth, and quantity, of microspeaker diaphragm were defined and simulated with commercial finite element software-COMOSL Multiphysics. Results showed that the quantity and depth of pattern significantly influenced on the acoustic radiation, especially at lower frequencies. The stiffness of diaphragm decreased with increases in quantity and depth of pattern. In addition, f for both conditions shifted to lower frequency and bandwidth of microspeaker was extended. Increasing the angle of pattern, resulted in more solid diaphragm and slight increase in efficiency.

关键词： Microspeaker Pattern of diaphragm Finite element method

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Parametric Analysis on the Geometry of Magnetic system for Subwoofer with FEMM

Parametric Analysis on the Geometry of Magnetic System for S...

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2018 3rd International Conference on Computational Modeling, Simulation and Applied Mathematics (CMSAM 2018)

作者： Yu-Cheng Liu Shu-Chien Wu Jiun-Yen Chen Bachelor's Program in Precision System Design Feng Chia University Master's Program of Electro-Acoustics Feng Chia University

The aim of this study is to investigate the distributions of magnetic flux and the variations in B curve for a novel design of loudspeaker magnetic system. Two different geometries, simulated with commercial finite element software-(FEMM) are presented, as well as an optimized design for the geometry of magnetic system. Results showed that changes in the inner side geometry obviously influence the distributions of magnetic field. In addition, the maximal magnetic force shifts to the position of lowest cross-sectional area. Meanwhile, B curve not only reduces the B level, but also loses the original uniformity in the air gap. Thus, the distortion caused from magnetic system will increase. Based on the original design, the new design not only maintains the flat B curve, but also saves on the amount of material of required for the magnetic system by around 31%.

关键词： Subwoofer Magnetic flux B curve NRT Finite element method

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A Numerical Method for Reversely Generating a Pair of Conjugated Rotor Profiles of Twin-screw Compressor from the Measured Profile Data

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Procedia CIRP 2017年 63卷 483-487页

作者： Ruei-Hung Hsu Yu-Ren Wu Zi-An Chen Bachelor's Program in Precision System Design Feng Chia University Taiwan R.O.C. Department of Mechanical Engineering National Central University Taiwan R.O.C.

Reverse engineering technique is generally practiced to reconstitute the original conjugated rotor profiles from the measured point data with profile deviation for further evaluating performance of the competitor's same-level products in the twin-screw compressor manufacturing industry. However, it is time-consuming when synthesizing and restoring the original rotor profiles via either trial or enveloping methods. This paper proposed a numerical method, named meshing clearance elimination (MCE) method, for approaching pairs of conjugated male and female rotor profiles from the discrete measured profile points. By using this method, the clearance between two screw rotors can be attained via the normal rack generation computation and then eliminated by proportionally distribute the normal compensation onto the measured rotor profiles to obtain the “ideal” rotor profiles to avoid numerical divergence in the following compressor performance computation. Two kinds of rotor profiles measured from CMM (Coordinates Measurement Machine) were demonstrated in the numerical examples to show the effectivity and advantages of the MCE method.

关键词： twin-screw compressor rotor profile meshing clearance

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Variations in the acoustic measurement of earbud earphones in an ane-choic chamber due to changes in the earphone placement in ear Concha

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Canadian Acoustics - Acoustique Canadienne 2020年第4期48卷 29-40页

作者： Pawar, S.J. Liu, Y.C. Huang, Jin H. Department of Applied Mechanics Motilal Nehru National Institute of Technology Allahabad Prayagraj India Bachelor's Program in Precision System Design Feng Chia University Taichung Taiwan Department of Mechanical and Computer-Aided Engineering Feng Chia University Taichung Taiwan

The growth of consumer electronic products is encouraged by innovations and has stimulated the persistent development of earphones for high-quality sound reproduction. Earbud earphone is located in the concha of the human ear facing an ear-canal. The placement of earphones in the concha plays a remarkable role in the sound pressure level response of an earphone. In this study, ten earphones were tested for frequency response and total harmonic distortion using head and torso simulator in an anechoic chamber. Three positions and two orientations of earphones in the concha were identified for measurement. Based on the responses of all earphones at all orientations and positions, it is concluded that there is a variation in the frequency response and total harmonic distortion. Even though the variation is small in magnitude, its effect on sound perception, sound exposure, and the hearing threshold is phenomenal. Based on the proposition presented in this work and the safe daily sound exposure, it has been determined that the variation in the frequency response affects the perceived loudness of sound and can cause signif-icant differences in the daily sound exposure limit for a human being. © 2020, Canadian Acoustical Association. All rights reserved.

关键词： Frequency response

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Application of programmable Logic Controller to Build-up an Intelligent Industry 4.0 Platform

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Procedia CIRP 2017年 63卷 150-155页

作者： Jian-Yu Chen Kuo-Cheng Tai Guo-Chin Chen Bachelor's Program of Precision System Design Feng Chia University No. 100 Wenhwa Rd. Seatwen Taichung 407 Taiwan Department of Mechanical and Computer-Aided Engineering Feng Chia University No. 100 Wenhwa Rd. Seatwen Taichung 407 Taiwan

Industry 4.0 is initiated by the German government as a high level technology strategy in order to keep Germany in a global leading position in manufacturing, also intends to solve energy and aging issues in parallel. Germany has proposed the “Reference Architecture Model Industries 4.0” which is based on the regulations published by the International Electrotechnical Commission. The manifestation of Industry 4.0 can be achieved by the realization of digital factory. And it's emphasized on total integration with Cyber Physical system as its core technology, via Internet of Things to realize the operational environment of human machine interaction, and the utilization of Big Data for decision making. The research motivation of this thesis is to utilize Totally Integrated Automation Portal as a digital factory software development platform, to achieve the fundamental educational requirements of digital factory, and to understand Industry 4.0 concept. Methodology of this research is based on a set of experimental and training mechanism, the sequence of machine movements is controlled by a programmable Logic Controller, and this PLC has to be complied with IEC61131 International Standard. Regarding communication technology also to be complied with IEC61158 and IEC62541 e.g. PROFINET and OPC UA protocol. And finally realizing the operational environment of human machine interaction via smart phone according to the outcome of this research, it has been shown that total integration concept can be realized by single production machine. By standardization of factory environment and increasing the level of operational environment of human machine interaction, productivity and quality of production could be significantly increased. PLC could be used to analyze intelligent platform and comply with the Industry 4.0 standard at the same time.

关键词： I4.0 Digitalization Factory PLC and IEC61131

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Quality Monitoring Methodology for Micro-Shrinkage of Thick-Walled Injection Molded Components

SSRN

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SSRN 2022年

作者： Huang, Ming-Shyan Chen, Jian-Yu Xiao, Yu-Qi Department of Mechatronics Engineering National Kaohsiung University of Science and Technology 1 University Road Yanchao Dist. Kaohsiung City824 Taiwan Bachelor’s Program of Precision System Design Feng Chia University 100 Wenhwa Road Seatwen Taichung City40724 Taiwan

Sink mark degrades the surface quality of the thick-walled injection molded components. An effective method for quantifying sink marks, and predicting the occurrence of such defects as a function of the injection molding process parameters, are of significant interest in improving the molding quality. The present study proposes a method for measuring the micro-shrinkage using a simple image-processing technique. Simulation and experimental trials are performed to investigate the effects of injection molding parameters on the quality of the polymer melt (as evaluated using quality indexes extracted from the pressure profiles within the chamber and the tie-bar elongation, respectively) and the quality of the final molded component. The sink mark is determined mainly by the holding pressure. The quality indexes revealed in this study are all highly correlated with micro-shrinkage. They provide a viable means of predicting the formation of sink marks and excessive micro-shrinkage in thick-walled injection molded components. © 2022, The Authors. All rights reserved.

关键词： Injection molding

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Crowning Analysis of Involute Helical Pairs Shaved by CNC Gear Shaving Machine with Two Synchronous Axes

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IOP Conference Series: Materials Science and Engineering 2018年第1期417卷

作者： Ruei-Hung Hsu Shih-Sheng Chen Bachelor Program in Precision System Design Feng Chia University No. 100 Wenhwa Road Seatwen Taichung 407 Taiwan Department of Mechanical Engineering National Chung Hsing University No. 250 Kuo-Kuang Road Taichung 40227 Taiwan

Gear Shaving is one of the most efficient and economical ways to finish gears after gear hobbing or gear shaping. In tradition, the shaved gear can be crowning by shaving machine with the rocking mechanism. In this paper, we propose a mathematical model of a CNC shaving machine with two synchronous axes. The proposed mathematical model can be used to calculate the crowning tooth surface of the gear in parallel-shaving process.

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Challenge - Naval force development

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Naval Engineers Journal 2004年第3期116卷 57-62页

作者： Hamilton, Charles S. Program Executive Officer for Ships REAR ADMIRAL HAMILTON is a native of Amityville New York. He attended Duke University graduating in May 1974 with a bachelor of science in zoology. He was commissioned in the Navy in May 1974 through the NROTC Program at Duke. Rear Adm. Hamilton's sea tours include electronics material officer and combat information center officer in USS Hawkins (DD 873) (1974 to 1976) fire control officer and missile officer in USS Coontz (DDG 40) (1976 to1978) operations officer in USS Callaghan (DDG 994) (1981 to 1984) executive officer USS Fox (CG 33) (1986 to 1988) and commanding officer USS O'Brien (DD 975) (1991 to 1993). Rear Adm. Hamilton's shore tours include anti-submarine warfare program analyst and administrative assistant to director Program Resource Appraisal Division (OP-91) Office of the Chief of Naval Operations (1984 to 1986) head Aegis Destroyer Section (OP-355F) and financial coordinator Aegis Cruiser Destroyer Branch Office of the Chief of Naval Operations (1988 to 1990) and military staff specialist for naval war-fare in the Office of the Under Secretary of Defense (Acquisition and Technology) (1994 to 1996). In May 1996 Rear Adm. Hamilton became program manager for the arsenal ship which was designed to provide massed precision fires in support of Fleet commander's warfighting requirements. After completing the first two design phases and passing significant acquisition reform lessons learned to the DD 21 Program Office Rear Adm. Hamilton closed down the Arsenal Ship Program in March 1998. From April 1998 to February 2000 Rear Adm. Hamilton served as deputy for Fleet in the Program Executive Office Theater Surface Combatants (PEO TSC-F). In this position he was responsible for Fleet Introduction and Lifetime Support of 120 surface combatants (DDG 51 CG 47 DDG 993 DD 963 FFG 7). Rear Adm. Hamilton served as program executive officer for Surface Strike (PEO (S)) from February 2000 until November 2002. As PEO (S) he managed the Zumwalt-class DD 21/DD (X) N

The challenges which stood as an obstacle to the naval force development are discussed. The main challenge in the national security environment is to be virtually available anywhere in the world at the behest of the national command. It is observed that in surface warefare coast guard has the most applicability and expansion of their surveillance area will help in engaging other vessels away from the manned platform. It is also observed that the relationship with mission modularity and the growth between the coast guard and the navy has attracted interest among the international community.

关键词： Marine engineering

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