Numerical Simulation of Vibration Pressure on the Hydraulic Performance of Round-Flow Emitter

2014 ◽  
Vol 1073-1076 ◽  
pp. 2205-2209
Author(s):  
Wei Cao ◽  
Jie Liu ◽  
Yue Ting Zhu ◽  
Qing Song Wei ◽  
Yu Sheng Shi

Conventional drip irrigation systems are working under constant working pressure, but the core component emitter is prone to clogging. Round-flow emitter is selected as the research object. Computational fluid dynamics software FLUENT 6.3 is applied to simulate the hydraulic performance of the round-flow emitter under the condition of vibration pressure. Vibration modes are selected as the sine waveform, triangular waveform and rectangle waveform. Three vibration parameters such as basic pressure, vibration period and vibration amplitude are taken as the factors to design the orthogonal experiment. Simulation results show that, water fluctuation and energy dissipation of round-flow emitter in vibration mode are better than that of constant pressure. The combination of basic hydraulic pressure 8m, vibration period 72s, vibration amplitude 6m is the optimal vibration parameters. The research of this paper provides a certain reference for selecting the vibration parameters of the vibration mode.

Author(s):  
Gudmund Kleiven

The Empirical Orthogonal Functions (EOF) technique has widely being used by oceanographers and meteorologists, while the Singular Value Decomposition (SVD being a related technique is frequently used in the statistics community. Another related technique called Principal Component Analysis (PCA) is observed being used for instance in pattern recognition. The predominant applications of these techniques are data compression of multivariate data sets which also facilitates subsequent statistical analysis of such data sets. Within Ocean Engineering the EOF technique is not yet widely in use, although there are several areas where multivariate data sets occur and where the EOF technique could represent a supplementary analysis technique. Examples are oceanographic data, in particular current data. Furthermore data sets of model- or full-scale data of loads and responses of slender bodies, such as pipelines and risers are relevant examples. One attractive property of the EOF technique is that it does not require any a priori information on the physical system by which the data is generated. In the present paper a description of the EOF technique is given. Thereafter an example on use of the EOF technique is presented. The example is analysis of response data from a model test of a pipeline in a long free span exposed to current. The model test program was carried out in order to identify the occurrence of multi-mode vibrations and vibration mode amplitudes. In the present example the EOF technique demonstrates the capability of identifying predominant vibration modes of inline as well as cross-flow vibrations. Vibration mode shapes together with mode amplitudes and frequencies are also estimated. Although the present example is not sufficient for concluding on the applicability of the EOF technique on a general basis, the results of the present example demonstrate some of the potential of the technique.


2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Kefan Yang ◽  
Youmin Wang ◽  
Kexun Fu

The hydraulic bulging technology of tubes can provide hollow parts with special-shaped cross sections. Its manufacturing process can effectively improve material utilization and product accuracy and reduce the number and cost of molds. However, the hydraulic bulging process of parts is very complicated. The size of the tube blank, the design of the loading route, and the forming process parameters will have an effect on the molding quality. Closed tubular torsion automobile beam is considered as the research object to study hydraulic bulging die design and optimize forming process parameters. CATIA software is used to design torsion beam product structure and hydraulic bulging die. AMESim software is employed to design hydraulic synchronous control system for cylinders on both sides of the hydraulic bulging die. Mathematical control model is established and verified in Simulink software. DYNAFORM software is applied to conduct numerical simulation of hydraulic expansion. The supporting pressure, molding pressure, friction coefficient, and feeding quantity are taken as orthogonal experiment level factors. Maximum thinning and maximum thickening rates are taken as hydraulic pressure expansion evaluation indexes to complete the orthogonal experiments. Main molding process parameters are analyzed via orthogonal experiment results and optimized by employing the Taguchi method. Optimal hydraulic bulging parameters are obtained as follows: supporting pressure of 20 MPa, molding pressure of 150 MPa, feeding quantity of 25 mm, and friction coefficient of 0.075. Simulation analysis results indicate that the maximum thinning rate is equal to 9.013%, while the maximum thickening rate is equal to 16.523%. Finally, the design of hydraulic bulging die for torsion beam was completed, and its forming process parameters were optimized.


2016 ◽  
Vol 4 (1) ◽  
pp. 5 ◽  
Author(s):  
A. Heidari ◽  
C. Brown

In the current research, ATR–FTIR and FT–Raman spectroscopies was used to investigate the effect of concentration on IR and Raman intensities and shifts of symmetric vibration modes of Ozone diluted by Cumene. The symmetric vibration mode of Ozone was observed at IR and Raman shifts of 850 and 975 cm-1, respectively. By reducing the concentration of Ozone, its intensity also was reduced and the symmetric vibration mode of Cumene was observed at IR and Raman shifts of 1050 and 1185 cm-1, respectively. The concentration has not influence on IR and Raman shifts of vibration modes. The experimental results were confirmed the linear dependency of IR and Raman intensities to the concentration of sample.Ozone molecule (left illustration) and Cumene molecule (right illustration) (Santiago-López et al. 2010; Guevara-Guzmán et al. 2009; Pereyra-Muñoz et al. 2006; Foucaud et al. 2006; Elsayed 2001; van Hoof et al. 1997; Chrostowski et al. 1983; Boehme et al. 1992; Catalá et al. 2013; Balvers et al. 1992; Marker et al. 1986).


Author(s):  
Wen Nan Cheng ◽  
Chih Chun Cheng ◽  
Gary H. Koopmann

A design method for achieving minimum sound radiation from a beam is presented. The strategy is to form a series of cylindrical dimples on the beam surface in order to make one or more vibration modes of this dimpled beam have the same shape as the weak modes. Consequently, the dimpled beam behaves as a weak radiator when one or more vibration modes are excited. Instead of minimizing the radiated sound power at a specific frequency or in a bandwidth, the objective is to maximize the modal assurance coefficient (MAC) which quantifies resemblance between the vibration mode of a dimpled beam and a weak mode. To perform this strategy, two key issues are addressed in this paper. The first is to determine the so-called weak mode of a beam. And the second is how to determine the required dimple size and the dimple location on this beam so that the dimpled beam may have vibration modes resembled to the weak modes. A methodology to do so based on the finite element method and the mode assurance criteria is proposed. Results show that the radiation efficiency of the dimpled beam after optimization using MAC as the objective is generally lower than the uniform beam. However, the effectiveness of this strategy depends on how close in shape between the vibration mode of the dimpled beam and the designated weak mode.


2012 ◽  
Vol 550-553 ◽  
pp. 3323-3330 ◽  
Author(s):  
Jian Feng Xu ◽  
Ling Long ◽  
Hui Ren Hu ◽  
Yan Bo

A series of starch-based styrene acrylate emulsion (SAE) modified with water-resistance agent were prepared by introducing rosin, organosilane(γ-amino propyl triethoxysilane (KH550), γ-(2,3-epoxypropoxy)-propytrimethoxysilane(KH560) and γ-methacryloxypropyl trimethoxy silane (KH570) as the functional monomer, respectively. In the reaction, starch(CS-8), which is low relative viscosity, was used as the emulsifier and dispersant. The optimum conditions of the reaction had especially been studied by orthogonal experiment and then the emulsion properties and surface sizing behaviors of the SAE modified with different kinds of water-resistance agents were compared. Finally, the products which had excellent properties were characterized and the sizing performance was investigated. The results showed that the excellent performance and good sizing effects of styrene acrylate emulsion (SAE) were achieved when the reaction conditions were as follows: rosin was selected as the water resistance-agent with the dosage of 2%(wt), the reaction temperature was 88°C, the mass ratio of St and BA was 9:11, the stirring speed was 130 round per minute and the dosage of initiator (APS), cationic monomer (DM) and CS-8 was 0.5%, 2%(wt) and 7%, respectively. The water-resistance properties of starch-based SAE were significantly improved by using rosin as the water-resistance agent and the surface sizing performance were better than that of the commercial AKD.


2012 ◽  
Vol 602-604 ◽  
pp. 49-52
Author(s):  
Jing Xue Liu ◽  
Jia Lu Li

The paper presents an analysis of the vibration damping properties of three-layer-connected biaxial weft knitted fabric (TBWK), which are constituted of carbon fibers as inserted yarns and polyester yarns as knitted yarns impregnated in an epoxy matrix with resin transfer molding (RTM) technique. Damping parameters were investigated using beam test specimens and an impulse technique. Several vibration parameters were varied to characterize the damping behavior in different amplitudes, natural frequencies and vibration modes. The results obtained show that the damping ratio of TBWK composites decreases with the increasing of fiber volume fraction in all the three vibration modes. The vibration test also indicates that the natural frequency of the TBWK composites increases with the increasing of fiber volume fraction (Vf) in all the three modes.


2011 ◽  
Vol 422 ◽  
pp. 379-382
Author(s):  
Wei Chuang Quan ◽  
Mei Fa Huang ◽  
Zhi Yue Wang ◽  
Da Wei Zhang

Led die bonder used for bond lead frame and chip is one of the key equipment of led production line. The swing-arm is an important component of led die bonder and its dynamic characteristics will directly affect the piece accuracy. At present, the accuracy and efficiency of led die bonder are limited because of the vibration of the swing-arm. In solving this problem, a three-dimensional finite-element model for swing-arm is built to provide analytical frequencies and vibration modes. Then the modal distribution and vibration mode shapes for swing-arm are obtained after analyzing the modal by ansys10.0. Finally the dynamics effects of this structure by modal frequency and vibration mode are analyzed. The modal analysis of structural would provide the reference to dynamics analysis and structural optimization for swing-arm in practical use.


2018 ◽  
Vol 189 ◽  
pp. 11004
Author(s):  
Jun Chen ◽  
Tao Zhou

In this work, a novel vibration parameter measure instrument of rotate machine using a accelerometer is proposed. The ADXL203 micro accelerometer is used as the sensor of the instrument based on the MEMS (Micro Electro Mechanical System) technology. The mathematical modeling of the vibration is finished by the simple harmonic vibration theory. The noise of the system is disposed by the differential noise reduction circuit. The experiments such as differential noise reduction, frequency and vibration amplitude measurement are finished on the platform. The results indicate that the instrument is useful and effective.


2011 ◽  
Vol 236-238 ◽  
pp. 1803-1806
Author(s):  
Jia Liu ◽  
Shun Xiang Li

The mechanism and method were deduced on surface modification of nano-ZnO by titanate coupling agent. EVADPE/ZnO nanocomposite material was prepared, and the tensile strength was tested. Three relatively optimal groups of process parameters were obtained by orthogonal experiment, BP-GA model and BP-PSO model respectively, in which the parameter obtained through BP-GA model was equal to that obtained through BP-PSO model. The iterative times of BP-PSO algorithm were smaller than that of BP-PSO algorithm. With analysis, it was showed that the group of process parameters obtained by BP-GA model and BP-PSO model based on the orthogonal experiment data were much better than that group obtained by orthogonal experiment. The optimal velocity of BP-PSO algorithm was faster than that of BP-PSO model.


2012 ◽  
Vol 538-541 ◽  
pp. 1755-1761
Author(s):  
Man Feng Gong ◽  
Zhong Li ◽  
Jue Dong

Reinforcing rib structure in the aluminum heating-plate automatic casting system was modeled by ANSYS, the static and dynamical problems were studied. Deformation and stress were calculated by static analysis, the front ten orders inherent frequency, critical rotating-speed and vibration modes were analyzed by modal analysis technology, vibration amplitude responses were obtained by harmonic response analysis. The maximum deformation value of reinforcing rib structure was less than 2mm (irrespective of the structure self-weight); the maximum equivalent stress was about 64.8MPa. It showed that the reinforcing rib structure could effectively avoid the resonance region, and the maximum vibration mode according to its inherent frequency appeared at the edge of the structure, some vibration modes were orthogonal, the main vibration modes appeared in the forms of bending, torsion, but the stretching vibration mode was scarce. The low orders inherent frequency greatly effected more than the high orders inherent frequency by harmonic response analysis, and the maximum deformation value was 25μm in low order vibrations. The conclusion is that the reinforcing rib structure fulfills design requirements and operates softly.


Sign in / Sign up

Export Citation Format

Share Document