A5003518665- Aerodynamics and Acoustics in Jet Flows
- High-Velocity Impact and Material Behavior
- Acoustic Wave Phenomena Research
- Computational Fluid Dynamics and Aerodynamics
- Aerodynamics and Fluid Dynamics Research
- Vehicle Noise and Vibration Control
- Energetic Materials and Combustion
- Structural Response to Dynamic Loads
- Aerospace and Aviation Technology
- Fluid Dynamics and Turbulent Flows
- Electromagnetic Launch and Propulsion Technology
- Wind and Air Flow Studies
- Fluid Dynamics Simulations and Interactions
- Aeroelasticity and Vibration Control
- Network Security and Intrusion Detection
- Anomaly Detection Techniques and Applications
- Combustion and Detonation Processes
- Aerosol Filtration and Electrostatic Precipitation
- Geophysical Methods and Applications
- Cavitation Phenomena in Pumps
- Advanced Measurement and Detection Methods
- Plasma and Flow Control in Aerodynamics
- Face and Expression Recognition
- Structural Health Monitoring Techniques
- Underwater Acoustics Research
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2010-2025
North University of China
2015-2024
Dongguan University of Technology
2024
Applied Precision (Slovakia)
2024
East China Normal University
2007-2024
PLA 306 Hospital
2023
National University of Defense Technology
2006-2018
Southwest Jiaotong University
2012-2017
Hong Kong Baptist University
2012
Beijing University of Posts and Telecommunications
2012
To achieve effective and efficient detection of Alzheimer's disease (AD), many machine learning methods have been introduced into this realm. However, the general case limited training samples, as well different feature representations typically makes problem challenging. In paper, we propose a novel multiple kernel-learning framework to combine multimodal features for AD classification, which is scalable easy implement. Contrary usual way solving in dual, look at optimization from new...
Contra Rotating Open Rotor (CROR) propulsion systems have come back into focus as a possible economic and environmentally friendly powerplant for future transport aircraft. Having been widely applied to the simulations of single rotation propellers, DLR CFD code TAU aeroacoustic analysis tool APSIM employed complex aerodynamics aeroacoustics this type aircraft system. In order demonstrate codes applicability these types well develop an understanding impact configuration variations, generic...
<title>Abstract</title> This paper presents the activities performed in GARTEUR Action Group HC/AG-26 to study acoustic and aerodynamic characteristics of small rotor configurations, including influence rotor-rotor interactions. will focus on comparisons between numerical wind tunnel results a provided by DLR. The models included Rotor/Rotor/Pylon isolated, tandem coaxial configuration. experiments for acoustics were DLR’s Acoustic Wind Tunnel Braunschweig (AWB) PIV test CIRA within joint...
The main goal of the present study is to explore noise mitigation potential using an active control strategy based on rotor phase synchronization. This work focused effects inflow velocity interference effect. does not affect at which phenomenon observed, as expected. On other hand, intensity pressure fluctuations influenced by for all shift conditions investigated. Specifically, increases, maintaining a constant rotational speed, in Overall Sound Pressure Level graphs, reduction...
An ideally shaped charge warhead is an effective weapon against armored targets. The use of the gathering energy effect generated by explosion drives liner to form a jet, which can penetrate target. Existing warheads often metal liner. Herein, we discuss characteristics polymer liners. To study expansive jet formed liner, three materials with different properties—polytetrafluoroethylene (PTFE), nylon (PA), and polycarbonate (PC)—were selected. Using smooth particle hydrodynamics (SPH) method...
Sensor networks are distributed made up of small sensing devices equipped with processors, memory, and short-range wireless communication. They differ from traditional computer in that they have resource constraints, unbalanced mixture traffic, data redundancy, network dynamics, energy balance. Work within sensor (WSNs) Quality service (QoS) has been isolated specific either on certain functional layers or application scenarios. However the area quality remains largely open. In this paper we...
Abstract This paper addresses the acoustic and aerodynamic characteristics of small rotor configurations, including influence rotor–rotor interactions. For this purpose, a Rotor/Rotor/Pylon configuration is chosen for both test numerical simulations. The wind tunnel experiments on various were performed in DLR’s Acoustic Wind Tunnel Braunschweig (AWB). involve isolated rotors, rotors tandem coaxial hover forward flight. simulations, an unsteady free wake 3D panel method (UPM) used to account...
The jet generated through PTFE based inert material liner has the characteristics of low energy, density, and large aspect ratio, which can effectively achieve "penetration without explosion" explosive reactive armor. PTFE/Cu composite with various densities is prepared, to research roles preparation procedure density in destroy effect on Through numerical simulation research, it was found that there no reaction at all layer penetrated by sinter molded, while hot-pressing sintering extrusion...
The present study demonstrates the aerodynamic and acoustic optimization potential of a counter rotating open rotor. objective was to maximize propeller efficiency at top climb conditions minimize noise emission takeoff while fulfilling given thrust specifications two operating (takeoff climb) considered. Both objectives were successfully met by applying an efficient multi-objective procedure in combination with 3D RANS method. evaluation carried out coupled U-RANS analytic far field...
In order to solve the problem of inadequate penetration low-density jet penetrating shell charge, PTFE are modified by adding a certain fraction copper powder in matrix.This treatment helps increase material density and energy, as well improve static dynamic mechanical properties material.AUTODYN-2D finite element software is used simulate process which forms penetrates charge.The simulation experiment results show that comparison PTFE, PTFE/Cu have been significantly improved, has strong...
In a double-layer shaped charge (DLSC), the shock initiation of high-detonation-velocity explosive on low-detonation-velocity and collision detonation waves will produce overdriven (ODD). this study, mathematical model for calculating propagation path in DLSC is established. The calculation formulas ODD parameters near contact surface two explosives are given. addition, divided into three cases: normal incidence, oblique irregular incidence. process analyzed, method critical incident angle...
In the process of industrial production, manual assembly workpieces exists with low efficiency and high intensity, some human body has a certain degree danger. At same time, traditional machine learning algorithms are difficult to adapt complexity current field environment; change in environment will greatly affect accuracy robot’s work. Therefore, this paper proposes method based on combination vision YOLOv5 deep model obtain disk porous localization information, after coordinate mapping by...
Abstract Contra-Rotating Open Rotor (CROR) propulsion systems have seen renewed interest as an economic and environmentally friendly powerplant for future transport aircraft. Installation effects, i.e. the mutual interactions between airframe components rotors, a pronounced impact on aerodynamic aeroacoustic performance this type of engine. In past five years, DLR’s Institute Aerodynamics Flow Technology has performed number numerical studies investigating important aspects relating to...
With the widespread use of surveillance cameras, massive video data analysis has become an extremely labor-intensive work. In this paper, we propose efficient approach to detect anomaly in crowded scenes based on Spatially Localized Histogram Optical Flow (SL-HOF) descriptor and foreground classification. For motion description, new SL-HOF can not only preserve classic HOF descriptor's favorable capability characterizing velocity direction scene, but also depicts spatial distribution optical...
Preliminary results from a study to model the interaction aerodynamics and aeroacoustics of main tail rotor helicopter in subsonic flow are presented. The configurations studied are: 1) two bladed rotors hover, 2) four-bladed two-bladed climbing flight. unsteady pressure on surfaces is computed with an 3-D panel method full-span free wake simulation simultaneously rotating rotor. pressures serve as input Ffowcs Williams Hawkings-equation based acoustic code evaluate noise characteristics....
The renewed interest in the contra-rotating open rotor (CROR) as a potential highly efficient powerplant for future transport aircraft has prompted study into aerodynamic and aeroacoustic performance of this type engine at DLR. With significant technical challenges related to noise emissions installation effects remaining be addressed prior realisation viable type, generic pusher-configuration CROR propulsion system is presented, which focuses on impact aerodynamics emissions. two primary...
Detonation waves will bypass a wave shaper and propagate in the form of horn shaped charge. Horn can reduce incidence angle detonation on liner surface collide with each other at charge axis to overdriven detonation. Detection electronic components small-caliber terminal sensitive projectile that are limited by space often placed inside shaper, which cause no longer be uniform dense, weaken ability adjust waves. In this article, we design double-layer (DLSC) high-detonation-velocity...
This paper mainly studies the model design of a thin-film heat-flux sensor (TFHFS), and focuses on comparison three dynamic calibration methods. The primary motivation for studying this came from urgent need measurements in extreme environments, one-sidedness performance evaluation corresponding TFHFS. theoretical TFHFS was originally established principle temperature gradient basis thermal radiation boundary. Then, novel developed, which can be used at temperatures above 880 °C has high...