Application of LED Light Source in the Flow Imaging

2013 ◽  
Vol 380-384 ◽  
pp. 219-222
Author(s):  
Jin Bo Yao ◽  
Yue Ming Yang ◽  
Qin Yu Yang ◽  
Xiu Juan Liu ◽  
Dun Jin

Aircraft in flight, such as supercooled water droplets encountered icing conditions suitable for the external environment, the relevant parts of the body will freeze, making the aircraft's aerodynamic performance deterioration, severe endanger flight safety, in addition, the aircraft parked in the open winter months , there will be icing, you need to clean up before takeoff. We should grasp the mechanism of aircraft icing, environmental factors and easy to freeze parts of the body. This paper presents a simulation using the wind tunnel icing device icing wind tunnel simulations can reproduce the real situation of aircraft icing, for guiding practice and got good results.

2013 ◽  
Vol 380-384 ◽  
pp. 191-194
Author(s):  
Qin Yu Yang ◽  
Jin Bo Yao ◽  
Yue Ming Yang ◽  
Xue Wei Liu

Aircraft in flight, such as supercooled water droplets encountered icing conditions suitable for the external environment, the relevant parts of the body will freeze, making the aircraft's aerodynamic performance deterioration, severe endanger flight safety, in addition, the aircraft parked in the open winter months , there will be icing, you need to clean up before takeoff. We should grasp the mechanism of aircraft icing, environmental factors and easy to freeze parts of the body. This paper presents a simulation using the wind tunnel icing device icing wind tunnel simulations can reproduce the real situation of aircraft icing, for guiding practice and got good results.


1995 ◽  
Vol 7 (2) ◽  
pp. 21-23 ◽  
Author(s):  
S. Daan

The analysis of motivational systems underlying temporal organisation in animal behaviour has relied primarily on two conceptual functional frameworks: Homeostasis and biological clocks. Homeostasis is one of the most general and influential concepts in physiology. Walter Cannon introduced homeostasis as a universal regulatory principle which animals employ to maintain constancy of their ‘internal milieu’ in the face of challenges and perturbations from the external environment. Cannon spoke of “The Wisdom of the Body”, the collective of responses designed to defend the ideal internal state against those perturbations.


2021 ◽  
Author(s):  
Giuseppe Porpiglia ◽  
Paolo Schito ◽  
Tommaso Argentini ◽  
Alberto Zasso

<p>This paper introduces a new methodology to assess the influence of a windscreen on the crosswind performance of trains running on a bridge. Considering the difficulties encountered in both carrying out wind tunnel tests that consider the vehicle speed or complete CFD analyses, a simplified CFD approach is here discussed. Instead of simulating simultaneously the windscreen plus the moving train, the numerical problem is split into two parts: firstly, a simulation of the windshield alone is used to extract the perturbed velocity profile at the railway location; secondly, this profile used as an inlet condition for the wind velocity acting on an isolated train. The method is validated against a complete train plus windshield simulation in terms of pressure distribution and aerodynamic force coefficients on the train, and flow streamlines. This approach opens to the possibility of evaluating the aerodynamic performance of a vehicle on bridges considering bridge and vehicle as separated. Wind velocity profiles measured on the bridge during a wind tunnel campaign could be used as the initial condition for numerical simulations on vehicles.</p>


Author(s):  
Osman Balli ◽  
Yakup Kutlu

One of the most important signals in the field of biomedicine is audio signals. Sound signals obtained from the body give us information about the general condition of the body. However, the detection of different sounds when recording audio signals belonging to the body or listening to them by doctors makes it difficult to diagnose the disease from these signals. In addition to isolating these sounds from the external environment, it is also necessary to separate their sounds from different parts of the body during the analysis. Separation of heart, lung and abdominal sounds will facilitate digital analysis, in particular. In this study, a dataset was created from the lungs, heart and abdominal sounds. MFCC (Mel Frekans Cepstrum Coefficient) coefficient data were obtained. The obtained coefficients were trained in the CNN (Convolution Neural Network) model. The purpose of this study is to classify audio signals. With this classification, a control system can be created. In this way, erroneous recordings that may occur when recording physicians' body voices will be prevented. When looking at the results, the educational success is about 98% and the test success is about 85%.


Aerodynamic drag has been experimentally estimated for scale models of a passenger car and a commercial truck in a wind tunnel. Polished surface has resulted up to 15 % reduction in drag force and add-on has resulted in 57% increase in drag force of a car model whereas 2.6 % reduction in drag force has resulted by using deflector in a commercial truck model. Anova analysis shows variation in mean of group data.


2007 ◽  
Vol 51 (02) ◽  
pp. 182-186
Author(s):  
Tracie J. Barber

The accurate prediction of ground effect aerodynamics is an important aspect of wing-in-ground (WIG) effect vehicle design. When WIG vehicles operate over water, the deformation of the nonrigid surface beneath the body may affect the aerodynamic performance of the craft. The likely surface deformation has been considered from a theoretical and numerical position. Both two-dimensional and three-dimensional cases have been considered, and results show that any deformation occurring on the water surface is likely to be caused by the wing tip vortices rather than an increased pressure distribution beneath the wing.


1969 ◽  
Vol 28 (02) ◽  
pp. 215-225
Author(s):  
Hamish N. Munro

The metabolism of the animal is equipped to adapt to changes in both the internal and the external environment. Among internal factors are activity versus rest and sleep, and the menstrual cycle in the case of the female. Metabolism must also respond to variations in the external environment, such as heat and cold, and notably the availability of food. Metabolic adaptation to nutrient supply is of two kinds. First, there are transient physiological adaptations to the intermittent intake of nutritionally adequate meals. These short-lived adaptations account for a large part of the diurnal variations that have been observed in the protein metabolism of mammals (Wurtman, 1969). Secondly, long-term adaptive reactions occur when there is a decrease in availability of an essential nutrient in the diet. Under such circumstances, tissue constituents are lost to varying degrees from different parts of the body. It is proposed to discuss here mainly short-term physiological adaptations to variations in amino acid supply and their relevance to the needs of the body for dietary protein. Adaptive changes resulting from long-term protein deficiency are considered in the paper by Waterlow &amp; Stephen (1969).


Fluids ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 34
Author(s):  
Pengtao Shi ◽  
Jihai Liu ◽  
Yingsong Gu ◽  
Zhichun Yang ◽  
Pier Marzocca

Aiming at the experimental test of the body freedom flutter for modern high aspect ratio flexible flying wing, this paper conducts a body freedom flutter wind tunnel test on a full-span flying wing flutter model. The research content is summarized as follows: (1) The full-span finite element model and aeroelastic model of an unmanned aerial vehicle for body freedom flutter wind tunnel test are established, and the structural dynamics and flutter characteristics of this vehicle are obtained through theoretical analysis. (2) Based on the preliminary theoretical analysis results, the design and manufacturing of this vehicle are completed, and the structural dynamic characteristics of the vehicle are identified through ground vibration test. Finally, the theoretical analysis model is updated and the corresponding flutter characteristics are obtained. (3) A novel quasi-free flying suspension system capable of releasing pitch, plunge and yaw degrees of freedom is designed and implemented in the wind tunnel flutter test. The influence of the nose mass balance on the flutter results is explored. The study shows that: (1) The test vehicle can exhibit body freedom flutter at low airspeeds, and the obtained flutter speed and damping characteristics are favorable for conducting the body freedom flutter wind tunnel test. (2) The designed suspension system can effectively release the degrees of freedom of pitch, plunge, and yaw. The flutter speed measured in the wind tunnel test is 9.72 m/s, and the flutter frequency is 2.18 Hz, which agree well with the theoretical results (with flutter speed of 9.49 m/s and flutter frequency of 2.03 Hz). (3) With the increasing of the mass balance at the nose, critical speed of body freedom flutter rises up and the flutter frequency gradually decreases, which also agree well with corresponding theoretical results.


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