Hybrid aerial underwater vehicles (HAUV) are newly borne vehicle concepts, which could fly in the air, navigate underwater, and cross air-water surface repeatedly. Although there many problems to be solved, advanced concept, combines integrated multidomain locomotion of both water air mediums is worth exploring. This paper presents water–air trans-media status HAUV from perspective configuration control. It shows that multi-rotor relatively mature has achieved a stable process The morphing...

Abstract Schlieren and shadowgraph photography has been widely used to offer insight into the flow field in aerospace engineering due their ease of application. The high-speed schlieren techniques are typically applied investigation unsteady shock wave structure including reflection patterns wave/boundary layer interactions, etc. Generally, qualitative analysis is performed based on image sequences. To process analyze large data set images quantitatively, especially for detection tracking, a...

To improve the performance of permanent magnet-assisted synchronous reluctance motors for wind power generation during operation and reduce cogging torque, an improved iterative Taguchi optimization algorithm was used to perform multi-objective motors. Taking slot width, air gap length, magnet thickness, magnetic isolation bridge width as variables, electromagnetic efficiency are analyzed using optimal factor combination obtained by orthogonal test methods. Ansoft Maxwell verifies...

Abstract Multirotor Hybrid aerial underwater vehicle (HAUV) is the which could operate both in air and powered by multi-rotors. The water-air trans-domain process very changeling for change of floatage added mass ‘ground effect’. This paper researched on effect intelligent algorithms trans-media control. And genetic algorithm (GA) based radial basis function (RBFNN) proportional-integral-derivative (PID) controllers are developed process. Then simulations conclusions made these two...

The scale difference between the real flight vehicle and experimental model results in Reynolds number effect, which makes it unreliable to predict aerodynamic characteristics of vehicles by wind tunnel testing. To understand mechanism effects on supercritical wing that is commonly used transport aircraft more detail, surface pressure tests a reference with wing-body configuration were conducted European Transonic Windtunnel (ETW) at different numbers. There are 495 taps total equipped test...

Based on the complex structural characteristics of permanent magnet-assisted synchronous reluctance motors (PMA-SynRMs), this paper proposes a multi-objective optimization design method for motor using composite algorithm. Firstly, power density, electromagnetic torque, cogging and torque fluctuation coefficient were used as targets based parametric analysis data 14 structure variables, where sensitivity helped select eight variables. Secondly, prediction model was fitted genetic...

To systematically and comprehensively analyze the effects of different aging environments on failure aluminum alloy/CFRP (Carbon Fiber Reinforced Plastics) composite bonded shear butt joints, seven typical room temperature (23°C/20%RH, RT), high-temperature (80°C/20%RH, HT), low (−40°C, LT), cycles (−40 ~ 80°C/20%RH, TC), immersed in water at (IRT), high humidity (80°C /95%RH, HTHH), hygrothermal (−40°C 80°C HC) were selected to perform tests. The composition analysis revealed that adhesive...

A simultaneous surface pressure and displacement measurement method that integrates pressure-sensitive paint (PSP) binocular stereophotogrammetry is proposed. The assays were completed on the Φ4 m rotor test stand at China Aerodynamic Research Development Center (CARDC). single-shot lifetime approach was utilized to acquire instantaneous field a blade coated with PSP. At same time, PSP feature points used obtain 3D coordinates of stereo cameras, which yielded field. experimental results...

In order to assess the rationality of rated shield support capacity (RSSC) experienced selection and guide reasonable RSSC for subsequent working faces each coal seam, coupling relationship between roof strata was revealed during seams mining. According whether fractured rock blocks generated by main are articulated upper seam has been mined influenced on lower two structure mechanical models thick calculation methods a given load proposed. addition, method model maximum (MSSC)...

No AccessTechnical NotesAutomatic Shock Detection, Extraction, and Fitting in Schlieren Shadowgraph VisualizationGuoshuai Li, Konstantinos Kontis Zhaolin FanGuoshuai LiChina Aerodynamics Research Development Center, 621000 Mianyang, People's Republic of China, KontisUniversity Glasgow, Scotland G12 8QQ, United Kingdom FanChina ChinaPublished Online:23 Feb 2021https://doi.org/10.2514/1.J059667SectionsRead Now ToolsAdd to favoritesDownload citationTrack citations About References [1] Settles...

In response to the structural optimization problem of PCB stator coreless disc motors, orthogonal surface method was used optimize motor structure, preliminarily determine basic parameters motor, and conduct experiments on based design objectives. The factors were quantity magnetic pole rotor p, ratio main/auxiliary sizes Rnd, thickness Tm permanent magnet, air gap length δ. torque Td, amplitude density Bδ, waveform distortion rate THD as that cause reach a maximum minimum. Due use plates...

Wind tunnel test is an effective means to obtain aerodynamic performance of aircraft. Due the limitation conditions and cost, data obtained directly from are often small incomplete, so it meaningful build accurate prediction model meet engineering application. In this paper, traditional interpolation method, Kriging Support Vector Machine method RBF neural network used a transport aircraft aspect ratio aircraft, advantages shortcomings these methods compared analyzed. The results show that...

With the actual demand of market, miniaturized high density packaging components is becoming more and common. System ln a package enables higher functional integration in limited space. Flip chip new surface mounting technology for microelectronics manufacturing. In terms substrate design, traditional circular FC Bump design has many layers cost. this paper, oval solder bump introduced to reduce number required cost improve production efficiency substrate.

Given the growing popularity of fully mechanized longwall mining, hydraulic shields have emerged as most crucial pieces equipment whose rated support capacities are a significant assurance for safe extraction coal seams. Based on in 1,692 panel No.9 seam Qianjiaying mine, detailed study reasonable shield capacity under an extremely close goaf was conducted using field measurements, theoretical analyses, and system development. The results show that ZY4800-13/32 employed is unreasonable owing...

Abstract To visualize the flow in test section of an indraft supersonic wind tunnel University Glasgow as long possible, a background-oriented schlieren system was built up preliminarily. A MATLAB program based on random dot algorithm developed this study provides fully customizable tool to generate background patterns with different sizes and densities. Background produced by in-house then can be printed common ink-jet printer. enhance signal-noise ratio measurement system, white reflective...

Before re-entry flight or parachute deployment landing in low-altitude escape lifesaving flight, spaceship capsule will experience a low-supersonic, transonic and subsonic speed stage. In order to ensure successful safe this stage, it is necessary accurately predict the high-speed aerodynamic characteristics its stable flight. Conventional wind tunnel force test can only obtain macroscopic such as drag, lift, trim static stability of capsules, but cannot achieve detailed flow structure. For...