A Study on the Aerodynamic Characteristics for a Two-Dimensional Trajectory Correction Fuze

2014 ◽  
Vol 703 ◽  
pp. 370-375 ◽  
Author(s):  
Jie Min Li ◽  
Guang Lin He ◽  
Hao Yang Guo
Keyword(s):  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Aerodynamic Characteristics ◽  
Two Dimensional ◽  
Roll Control ◽  
Speed Range ◽  
The Common ◽  
Trajectory Correction ◽  
Control Forces ◽  
Targeting Accuracy

This study researched the aerodynamic characteristics of a two-dimensional trajectory correction fuze used for the common artillery ammunition, which increases the targeting accuracy by decreasing the circular error probability. The correction fuze has a pair of fixed canard and a pair of steering canards for roll control and guidance. In this study, computational fluid dynamic (CFD) simulation is performed to study the aerodynamic characteristics of the trajectory correction fuze. The primary purpose of this performance was to predict the aerodynamic coefficients and flow field over a spin-stabilized projectile with the correction fuze. Calculation covered from-10 degrees to 10 degrees steering canards deflection over speed range from Mach 0.6 to 3. The results showed the variation law in the rotary moment of correction module and the control forces of the steering canards with the Mach varying, providing aerodynamic reference for the research of trajectory correction projectiles in the future.

scholarly journals Analisis karakteristik aerodinamika telescopic wing dengan konfigurasi sayap flying wing dan glider menggunakan metode pendekatan simulasi CFD

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Azhim Asyratul Azmi ◽  
Satriawan Dini Hariyanto ◽  
Arif Hidayat
Keyword(s):  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Angle Of Attack ◽  
Leading Edge ◽  
Aerodynamic Characteristics ◽  
Morphing Wing ◽  
Aircraft Wing ◽  
High Lift ◽  
Tip Vortices ◽  
Wing Tip

A telescopic wing is a shape-changing method of the aircraft wing known as the morphing wing system. Wingspan extends capability on telescopic wing increasing the aspect ratio to get a high lift force. The telescopic wing on a flying wing configuration as an external wing and glider wing as an internal wing can be used to increase the coefficient lift (CL) when carrying out special missions. The aerodynamic characteristics using the Computational Fluid Dynamic (CFD) simulation approach is presented. For the 40% internal wingspan, the highest CL increment was 12.9% at a 10o angle of attack. For the 50% internal wingspan, the highest CL increment was 14.9% at a 10o angle of attack. on the 40% internal wing, the highest coefficient drag (CD) increment was 4.7%, and the largest CD increment on 50% internal was 9.5% at the angle of attack of 20o. The pressure distribution along the internal wingspan was uneven from an angle of attack of 15o due to the wing tip vortices of the external wing. Streamline pattern shown a bubble separation from the leading edge at an internal wing root by external wing tip vortices.Keywords: Morphing wing, telescopic wing, flying wing, glider

Analysis of Temperature and Residence Time of the Exhausts in the Combustion Chamber of an Incinerator Plant

2008 ◽  
Author(s):  
M. Costa ◽  
M. Dell’Isola ◽  
N. Massarotti ◽  
A. Mauro
Keyword(s):  
Combustion Chamber ◽  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Waste Incineration ◽  
Numerical Approach ◽  
Full Scale ◽  
Practical Applications ◽  
The Common ◽  
Semi Empirical ◽  
The Impact

The interest for energy recovery from waste incineration has increased over the years, in order to reduce the number of landfills and produce electricity and heat. At the same time, concern for the impact such processes have on the environment has also grown, and to reduce such an impact, new legislation is being enforced in Europe and Italy. In particular, important restrictions are imposed on the temperature of the exhausts in the combustion chamber, which must be kept above certain values for a given period of time, depending on the type of waste that is being incinerated. Such conditions can be rather difficult and certainly very expensive to monitor with acceptable accuracy. For this reason, in practical applications the temperature of the exhausts in the chamber is usually calculated through semi-empirical and approximate models that relate the temperatures in different sections of the chamber. In this work, the authors present a numerical approach for the analysis of such models that can be used to quantify the uncertainty on this type of measurement due to the common approximations used in full scale incineration plants. The analysis is based on the CFD simulation of the thermo-fluid-dynamic field in the combustion chamber of a full scale plant in Italy, whose results have verified based on a comparison with the data collected during an experimental campaign.

scholarly journals Impeller Optimization in Crossflow Hydraulic Turbines

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 313
Author(s):  
Marco Sinagra ◽  
Calogero Picone ◽  
Costanza Aricò ◽  
Antonio Pantano ◽  
Tullio Tucciarelli ◽  
...  
Keyword(s):  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Structural Safety ◽  
3D Fem ◽  
Good Efficiency ◽  
Standard Material ◽  
Variable Head ◽  
Hydraulic Turbines ◽  
Constructive Simplicity ◽  
Mechanical Optimization

Crossflow turbines represent a valuable choice for energy recovery in aqueducts, due to their constructive simplicity and good efficiency under variable head jump conditions. Several experimental and numerical studies concerning the optimal design of crossflow hydraulic turbines have already been proposed, but all of them assume that structural safety is fully compatible with the sought after geometry. We show first, with reference to a specific study case, that the geometry of the most efficient impeller would lead shortly, using blades with a traditional circular profile made with standard material, to their mechanical failure. A methodology for fully coupled fluid dynamic and mechanical optimization of the blade cross-section is then proposed. The methodology assumes a linear variation of the curvature of the blade external surface, along with an iterative use of two-dimensional (2D) computational fluid dynamic (CFD) and 3D structural finite element method (FEM) simulations. The proposed methodology was applied to the design of a power recovery system (PRS) turbine already installed in an operating water transport network and was finally validated with a fully 3D CFD simulation coupled with a 3D FEM structural analysis of the entire impeller.

scholarly journals Computational fluid dynamics (CFD) simulation analysis on retinal gas cover rates using computational eye models

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Makoto Gozawa ◽  
Yoshihiro Takamura ◽  
Tomoe Aoki ◽  
Kentaro Iwasaki ◽  
Masaru Inatani
Keyword(s):  
Cfd Simulation ◽  
Simulation Analysis ◽  
Fluid Dynamic ◽  
Fluid Analysis ◽  
Intraocular Gas ◽  
Pars Plana ◽  
Computational Fluid Dynamics Cfd ◽  
Multiple Breaks ◽  
Gas Volume ◽  
Wall Wettability

AbstractWe investigated the change in the retinal gas cover rates due to intraocular gas volume and positions using computational eye models and demonstrated the appropriate position after pars plana vitrectomy (PPV) with gas tamponade for rhegmatogenous retinal detachments (RRDs). Computational fluid dynamic (CFD) software was used to calculate the retinal wall wettability of a computational pseudophakic eye models using fluid analysis. The model utilized different gas volumes from 10 to 90%, in increments of 10% to the vitreous cavity in the supine, sitting, lateral, prone with closed eyes, and prone positions. Then, the gas cover rates of the retina were measured in each quadrant. When breaks are limited to the inferior retina anterior to the equator or multiple breaks are observed in two or more quadrants anterior to the equator, supine position maintained 100% gas cover rates in all breaks for the longest duration compared with other positions. When breaks are limited to either superior, nasal, or temporal retina, sitting, lower temporal, and lower nasal position were maintained at 100% gas cover rates for the longest duration, respectively. Our results may contribute to better surgical outcomes of RRDs and a reduction in the duration of the postoperative prone position.

scholarly journals Simulation of Hydraulic Cylinder Cushioning

2021 ◽  
Vol 13 (2) ◽  
pp. 494
Author(s):  
Antonio Algar ◽  
Javier Freire ◽  
Robert Castilla ◽  
Esteban Codina
Keyword(s):  
Dynamic Model ◽  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Computational Fluid Dynamic Simulation ◽  
Hydraulic Cylinder ◽  
Outlet Port ◽  
Optimal Behavior ◽  
Radial Movement ◽  
Mechanical Shocks ◽  
Radial Gap

The internal cushioning systems of hydraulic linear actuators avoid mechanical shocks at the end of their stroke. The design where the piston with perimeter grooves regulates the flow by standing in front of the outlet port has been investigated. First, a bond graph dynamic model has been developed, including the flow throughout the internal cushion design, characterized in detail by computational fluid-dynamic simulation. Following this, the radial movement of the piston and the fluid-dynamic coefficients, experimentally validated, are integrated into the dynamic model. The registered radial movement is in coherence with the significant drag force estimated in the CFD simulation, generated by the flow through the grooves, where the laminar flow regime predominates. Ultimately, the model aims to predict the behavior of the cushioning during the movement of the arm of an excavator. The analytical model developed predicts the performance of the cushioning system, in coherence with empirical results. There is an optimal behavior, highly influenced by the mechanical stress conditions of the system, subject to a compromise between an increasing section of the grooves and an optimization of the radial gap.

Modulating 2D Heterointerface with g-C3N4 Meshes: A Suitable Hetero-Layered Architecture for High-Power and Long-Life Energy Storage

2021 ◽  
Author(s):  
Yunping Wu ◽  
Wei Wei ◽  
Tianyi Ding ◽  
Sheng Chen ◽  
Rui Zhai ◽  
...  
Keyword(s):  
Energy Storage ◽  
High Power ◽  
2D Materials ◽  
Two Dimensional ◽  
Energy Storage Devices ◽  
Storage Devices ◽  
Efficient Energy ◽  
Layered Architecture ◽  
The Common ◽  
Long Life

Two-dimensional (2D) heterostructures combine the advantageous features of different 2D materials and represent advanced electrode architectures for development of efficient energy storage devices. However, the common 2D heterostructures made by...

scholarly journals Chimera Spectrum Diagnostics for Peptides Using Two-Dimensional Partial Covariance Mass Spectrometry

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3728
Author(s):  
Taran Driver ◽  
Nikhil Bachhawat ◽  
Leszek J. Frasinski ◽  
Jonathan P. Marangos ◽  
Vitali Averbukh ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Peptide Sequence ◽  
Two Dimensional ◽  
Peptide Ions ◽  
Finite Mass ◽  
Protein Database ◽  
Spectra Analysis ◽  
Fragment Ions ◽  
Single Precursor ◽  
The Common

The rate of successful identification of peptide sequences by tandem mass spectrometry (MS/MS) is adversely affected by the common occurrence of co-isolation and co-fragmentation of two or more isobaric or isomeric parent ions. This results in so-called `chimera spectra’, which feature peaks of the fragment ions from more than a single precursor ion. The totality of the fragment ion peaks in chimera spectra cannot be assigned to a single peptide sequence, which contradicts a fundamental assumption of the standard automated MS/MS spectra analysis tools, such as protein database search engines. This calls for a diagnostic method able to identify chimera spectra to single out the cases where this assumption is not valid. Here, we demonstrate that, within the recently developed two-dimensional partial covariance mass spectrometry (2D-PC-MS), it is possible to reliably identify chimera spectra directly from the two-dimensional fragment ion spectrum, irrespective of whether the co-isolated peptide ions are isobaric up to a finite mass accuracy or isomeric. We introduce ‘3-57 chimera tag’ technique for chimera spectrum diagnostics based on 2D-PC-MS and perform numerical simulations to examine its efficiency. We experimentally demonstrate the detection of a mixture of two isomeric parent ions, even under conditions when one isomeric peptide is at one five-hundredth of the molar concentration of the second isomer.

CFD Simulation of a Co-rotating Twin-screw Extruder: Validation of a Rheological Model for a Starch-Based Dough for Snack Food

2017 ◽  
Vol 14 (2) ◽  
Author(s):  
Giorgia Tagliavini ◽  
Federico Solari ◽  
Roberto Montanari
Keyword(s):  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Operating Conditions ◽  
Second Phase ◽  
Snack Food ◽  
Suitable Model ◽  
Twin Screw Extruder ◽  
Parallel Plates ◽  
Screw Extruder ◽  
Twin Screw

AbstractThe extrusion of starch-based products has been a matter of interest, especially for the pasta and the snack food production. In recent years, twin-screw extruders for snack food have been studied from both structural and fluid dynamics viewpoints. This project started from the rheological characterization of a starch-based dough (corn 34 wt%, tapioca 32 wt%), comparing viscosity values acquired in laboratory with different theoretical models found in literature. A computational fluid dynamic (CFD) simulation recreating the simple case of a fluid flow between two parallel plates was carried out to validate the former comparison. After the rheological validation was completed, the second phase of this work covered a 3D CFD simulation of the first part of the twin-screw extruder (feeding zone). The objective was to find a suitable model for describing the dough rheological behavior and the operating conditions of a co-rotating intermeshing twin-screw extruder. Once the model would be defined, it would allow to investigate several working conditions and different screws geometries of the machine, predicting the evolution of the product rheological properties.

scholarly journals N-(3-Chloro-1H-indazol-5-yl)-4-methoxybenzenesulfonamide

2013 ◽  
Vol 69 (11) ◽  
pp. o1632-o1632
Author(s):  
Hakima Chicha ◽  
El Mostapha Rakib ◽  
Latifa Bouissane ◽  
Mohamed Saadi ◽  
Lahcen El Ammari
Keyword(s):  
Hydrogen Bonds ◽  
Benzene Ring ◽  
Dihedral Angle ◽  
Title Compound ◽  
Two Dimensional ◽  
Common Edge ◽  
Compound C ◽  
Dimensional Network ◽  
The Common ◽  
The Mean

In the title compound, C14H12ClN3O3S, the fused five- and six-membered rings are folded slightly along the common edge, forming a dihedral angle of 3.2 (1)°. The mean plane through the indazole system makes a dihedral angle of 30.75 (7)° with the distant benzene ring. In the crystal, N—H...O hydrogen bonds link the molecules, forming a two-dimensional network parallel to (001).

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