Three-dimensional, Multi-Phase Modeling of a Water Nozzle Injection System Using Adaptive Re-Meshing

2018 ◽  
Author(s):  
William M. Dziedzic ◽  
Bruce T. Vu ◽  
Malay G. Shah
Keyword(s):  
Three Dimensional ◽  
Injection System ◽  
Nozzle Injection ◽  
Water Nozzle ◽  
Multi Phase

Three-dimensional multi-phase simulation of PEM fuel cell considering the full morphology of metal foam flow field

2021 ◽  
Vol 46 (3) ◽  
pp. 2978-2989 ◽  
Author(s):  
Guobin Zhang ◽  
Zhiming Bao ◽  
Biao Xie ◽  
Yun Wang ◽  
Kui Jiao
Keyword(s):  
Fuel Cell ◽  
Flow Field ◽  
Metal Foam ◽  
Three Dimensional ◽  
Pem Fuel Cell ◽  
Foam Flow ◽  
Multi Phase

scholarly journals Development and Preliminary Evaluation of an Integrated Individual Nozzle Direct Injection and Carrier Flow Rate Control System for Pesticide Applications

2019 ◽  
Vol 62 (2) ◽  
pp. 505-514 ◽  
Author(s):  
Joe D. Luck ◽  
Scott A. Shearer ◽  
Michael P. Sama
Keyword(s):  
High Pressure ◽  
Control System ◽  
Direct Injection ◽  
Injection System ◽  
Preliminary Evaluation ◽  
Variable Flow ◽  
Carrier Flow ◽  
Duty Cycles ◽  
Nozzle Injection ◽  
Injection Frequency

Abstract. Direct injection systems for agricultural spray applications continue to present challenges in terms of commercialization and adoption by end users. Such systems have typically suffered from lag time and mixing uniformity issues, which have outweighed the potential benefits of keeping chemical and carrier separate or reducing improper tank-mixed concentration by eliminating operator measurements. The proposed system sought to combine high-pressure direct nozzle injection with an automated variable-flow nozzle to improve chemical mixing and response times. The specific objectives were to: (1) integrate a high-pressure direct nozzle injection system with variable-flow carrier control into a prototype for testing, (2) assess the chemical metering accuracy and proper mixing at different combinations of injection valve frequency and duty cycle along with chemical pressure, and (3) assess the ability of the control system to ensure proper chemical dilutions and concentrations in the nozzle effluent resulting from step changes in target application rates. Laboratory experiments were conducted using the combined system. Results of these experiments showed that the open-loop control of the injectors could provide a means of accurately metering the chemical concentrate into the carrier stream. Chemical injection rates could be achieved with an average error of 5.4% compared to the target rates. Injection at higher duty cycles resulted in less error in the chemical concentration predictions. Discrete Fourier transform analysis showed that the injection frequency was noticeable in the nozzle effluent when the injector was operated at 3.04 MPa and 5 Hz (particularly at lower duty cycles). Increasing the injection pressure and operating frequency to 5.87 MPa and 7 Hz, respectively, improved mixing, as the injection frequency component was no longer noticed in the effluent samples. The variable-flow nozzle was able to maintain appropriate carrier flow rates to achieve product label chemical concentrations. In one case, the maximum allowable concentrate was exceeded, although the nozzle was able to recover in 0.5 s. Steady-state errors ranged from 2.5% to 7.5% for chemical concentrations compared to the selected chemical to carrier ratio (0.03614). This test scenario represented an application rate of 4.68 L ha-1 with velocity increases from 4.0 to 7.1 m s-1 and decreases from 7.1 to 4.0 m s-1, which were typical of the example field application data. Keywords: Pesticides, Precision agriculture, Spraying equipment, Variable-rate application.

Three-dimensional organization of the flow structure in a non-reactive model aero engine lean burn injection system

2014 ◽  
Vol 52 ◽  
pp. 164-173 ◽  
Author(s):  
Giuseppe Ceglia ◽  
Stefano Discetti ◽  
Andrea Ianiro ◽  
Dirk Michaelis ◽  
Tommaso Astarita ◽  
...  
Keyword(s):  
Flow Structure ◽  
Three Dimensional ◽  
Injection System ◽  
Lean Burn ◽  
Aero Engine

Experimental Analyses by SIMMER-III on Duct-Wall Failure and Fuel Discharge/Relocation Behavior

2013 ◽  
Author(s):  
Hidemasa Yamano ◽  
Yoshiharu Tobita
Keyword(s):  
Three Dimensional ◽  
Computer Code ◽  
Failure Behavior ◽  
Guide Tube ◽  
Control Rod ◽  
Duct Wall ◽  
Experimental Analyses ◽  
Multi Phase ◽  
Pool Formation ◽  
Good Agreement

This paper describes experimental analyses using SIMMER-III/IV, which are two/three-dimensional multi-component multi-phase Eulerian fluid-dynamics codes, for the purpose of the code validation. Two topics of key phenomena in core disruptive accidents were presented in this paper: duct-wall failure and fuel discharge/relocation behavior. To analyze the duct-wall failure behavior, the SCARABEE BE+3 in-pile experiments were selected. The SIMMER-III calculation was in good agreement with the overall event progression; which was characterized by coolant boiling, clad melting, fuel failure, molten pool formation, duct-wall failure, etc.; observed in the experiment. The CAMEL C6 experiment investigated the fuel discharge and relocation behavior through a simulated control rod guide tube, which is important in evaluating the neutronic reactivity. SIMMER-IV well simulated fuel-coolant interaction, sodium voiding, fuel relocation behavior observed in the experiment. These experimental analyses indicated the validity of the SIMMER-III/IV computer code for the duct wall failure and fuel discharge/relocation behavior.

scholarly journals 4D pine scale: biomimetic 4D printed autonomous scale and flap structures capable of multi-phase movement

2020 ◽  
Vol 378 (2167) ◽  
pp. 20190445 ◽  
Author(s):  
David Correa ◽  
Simon Poppinga ◽  
Max D. Mylo ◽  
Anna S. Westermeier ◽  
Bernd Bruchmann ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Image Correlation ◽  
Technical Structure ◽  
Cellulose Fibrils ◽  
Longitudinal Bending ◽  
Scale Structures ◽  
Multi Phase ◽  
Printing Techniques ◽  
Shape Changes ◽  
Phase Motion

We developed biomimetic hygro-responsive composite polymer scales inspired by the reversible shape-changes of Bhutan pine ( Pinus wallichiana ) cone seed scales. The synthetic kinematic response is made possible through novel four-dimensional (4D) printing techniques with anisotropic material use, namely copolymers with embedded cellulose fibrils and ABS polymer. Multi-phase motion like the subsequent transversal and longitudinal bending deformation during desiccation of a natural pinecone scale can be structurally programmed into such printed hygromorphs. Both the natural concept generator (Bhutan pinecone scale) and the biomimetic technical structure (4D printed scale) were comparatively investigated as to their displacement and strain over time via three-dimensional digital image correlation methods. Our bioinspired prototypes can be the basis for tailored autonomous and self-sufficient flap and scale structures performing complex consecutive motions for technical applications, e.g. in architecture and soft robotics. This article is part of the theme issue ‘Bioinspired materials and surfaces for green science and technology (part 3)’.

An Interfacial Debonding Model for Particle-Reinforced Composites

2002 ◽  
Author(s):  
H. T. Liu ◽  
L. Z. Sun ◽  
J. W. Ju
Keyword(s):  
Volume Fraction ◽  
Three Dimensional ◽  
Damage Mechanism ◽  
Interfacial Debonding ◽  
Elastic Behavior ◽  
Reinforced Composites ◽  
Stiffness Tensor ◽  
Particle Reinforced Composites ◽  
Damage Process ◽  
Multi Phase

To simulate the evolution process of interfacial debonding between particle and matrix, and to further estimate its effect on the overall elastic behavior of particle-reinforced composites, a two-level microstructural-effective damaged model is developed. The microstructural damage mechanism is governed by the interfacial debonding of reinforcement and matrix. The progressive damage process is represented by the debonding angles that are dependent on the external loads. For those debonded particles, the elastic equivalency is constructed in terms of the stiffness tensor. Namely, the isotropic yet debonded particles are replaced by the orthotropic perfect particles. The volume fraction evolution of debonded particles is characterized by the Weibull’s statistical approach. Mori-Tanaka’s method is utilized to determine the effective stiffness tensor of the resultant multi-phase composites. The proposed constitutive framework is developed under the general three-dimensional loading condition. Examples are conducted to demonstrate the capability of the proposed model.

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