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Effects of Avian Wings Color Patterns on Their Flight Performance:Experimental and Computational Studies

Journal of Bionic Engineering 2023年第2期20卷 683-710页

作者： Ahmed Aboelezz Brenden Herkenhoff mostafa hassanalian Department of Mechanical Engineering New Mexico Institute of Mining and TechnologySocorroNM87801USA

There are many theories behind the colors of a bird’s feathers.Many of these theories point to the color’s purpose to attract mates and hide from predators.Some recent investigations concluded that the dark colors of birds help in reducing the drag force during flight.A new theory is presented in the current research,which states that a bird's dark color not only reduces the drag,but the color pattern also improves the overall flight performance,and each color pattern has a different type of flight performance improvement.This difference in improvement is a result of variation in hot and cold surfaces on the bird skin as a result of the variation between light and dark feather colors.To prove this new theory,thermal images were captured of real bird wings under the effect of infrared waves.Also,a novel wind tunnel wing with the ability to adjust the temperature in desired locations and patterns on the wing’s surface was manufactured and tested to evaluate the effect of aerodynamics forces as a function in the surface temperature and the hot–cold regions.The collected data from this wing showed potential flight efficiency improvements of 20%,comparing the lift-to-drag ratio for specific heating cases,which could increase the flight range.Individually considering lift and drag,there were specific heating cases with corresponding angles of attack in which these parameters improved by up to 20%and 7%,respectively.Some heating cases could increase the lift at a low angle of attack,which is helpful in cruise flight performance,while some cases could increase the maximum lift coefficient by 6%.This is very helpful in lowering stall and the minimum flight speeds.Furthermore,some cases could increase the lift-to-drag ratio,which led to an increase in the flight range.To better understand the effect of the various patterns,computational fluid dynamics(CFD)simulations were conducted on the wing.The new theory was proved based on the CFD results and verified through the successful results from the wind tunnel experiments.

关键词： Aerodynamic loads CFD Drag Heated boundary layer Surface temperature

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Analytical and Observational Investigation of Colors Effects on Drag Reduction in Penguins

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Journal of Bionic Engineering 2022年第4期19卷 1036-1053页

作者： Grace Tenorio Anna Zagrai William Allen mostafa hassanalian Department of Mechanical Engineering New Mexico TechSocorroNM87801USA Cottonwood Valley Charter School SocorroNM87801USA Depertment of Biosciences Swansea UniversitySwanseaSA28PPUK

All 18 extant species of penguin are strongly countershaded,having dark dorsal and light ventral coloration.In this paper,the thermal effects of this body color in penguins are investigated through analytical and observational analyses.First,a thermal analysis that takes into account the environmental characteristics of penguins’habitats,fluxes,and morphology is used to analytically calculate penguin dorsal surface temperature.Next,a turbulent analytical solution for a heated boundary layer over a flat plate is applied to show that the dark color on the top of the penguins’bodies is very effective at skin drag reduction.To verify this result,a 2D model penguin is computationally analyzed at different temperatures,confirming in principle underwater skin drag reduction through color-based surface warming with efficiency savings of up to 30%.Finally,to study how color-based increases in body surface temperatures are maintained through foraging dives,thermal cameras are used to measure the surface temperature of captive penguins before and after dives.This study shows conceptually that dark dorsal coloration in penguins could have a significant influence on in-water drag.

关键词： Animal coloration Drag Energy balance Irradiation Penguin Thermal imaging Skin friction

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Energy Management of Echelon Flying Northern Bald Ibises with Different Wingspans and Variable Wingtip Spacing

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Journal of Bionic Engineering 2022年第1期19卷 44-61页

作者： mostafa hassanalian Amir Mirzaeinia Niyem Bawana Frank Heppner Department of Mechanical Engineering New Mexico TechSocorroNM87801USA Department of Computer Science and Engineering New Mexico TechSocorroNM87801USA Department of Biological Sciences University of Rhode IslandKingstonRI02881USA

In this paper,the flocking flight of Northern Bald Ibises(Geronticus eremita)and their induced drag during the flock are investigated.Northern Bald Ibises are long-range migratory birds.These birds fly in an echelon and V-shaped formation,possibly to reduce their drag;therefore,as a result,they may save energy to fly farther.The aerodynamic drag forces of each individual bird and the flock are modeled theoretically.Extensive analysis shows how,during flocking flight,the drag force reduces as the size of the flock increases.Additionally,wingtip spacing effects on the total drag of the flock are investigated.The fraction of drag reduction of individual ibises is also analyzed.Four initial arrangement scenarios are considered for flocks of ibises of different sizes in this study.Two shuffling algorithms are applied for position switching and energy balancing of the ibises during their flight.It is suggested that ibises can save energy by means of different arrangements of flock members during long flights.The results indicate that how different sizes of the birds can manipulate their positions to fly further and save energy during migration.

关键词： Drag Echelon Energy Flock Ibises Wingtips spacing

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Loader and Tester Swarming Drones for Cellular PhoneNetwork Loading and Field Test: Non-stochasticParticle Swarm Optimization

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Journal of Autonomous Intelligence 2019年第2期2卷 14-24页

作者： Amir Mirzaeinia mostafa hassanalian Mohammad Shekaramiz Mehdi Mirzaeinia Department of Computer Science and Engineering New Mexico Inst.of Mining and Tech.SocorroNMUSA Department of Mechanical and Aerospace Engineering New Mexico Inst.of Mining and Tech.SocorroNMUSA Department of Electrical and Computer Engineering Utah State UniversityLoganUTUSA Department of Electrical Engineering Amirkabir University of TechnologyTehranIran

Cellular network operators have problems to test their network without affecting their user experience. Testingnetwork performance in a loaded situation is a challenge for the network operator because network performance differswhen it has more load on the radio access part. Therefore, in this paper, deploying swarming drones is proposed to loadthe cellular network and scan/test the network performance more realistically. Besides, manual swarming dronenavigation is not efficient enough to detect problematic regions. Hence, particle swarm optimization is proposed to bedeployed on swarming drone to find the regions where there are performance issues. Swarming drone communicationshelps to deploy the particle swarm optimization (PSO) method on them. Loading and testing swarm separation help tohave almost non-stochastic received signal level as an objective function. Moreover, there are some situations that morethan one network parameter should be used to find a problematic region in the cellular network. It is also proposed toapply multi-objective PSO to find more multi-parameter network optimization at the same time.

关键词： Particle Swarm Optimization Swarming Drone Cellular Network Radio Optimization Loaded Network Test

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