Experimental and numerical investigation on drag reduction of non-smooth bionic jet surface

Gu, Yunqing; Zhao, Gang; Jin, Zheng; Zhaoyuan, Li; Liu, Wenbo; Muhammad, Farooq

doi:10.1016/j.oceaneng.2014.02.015

Cited by 48 publications

(17 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To the best of our knowledge, reducing the resistance in fluidinduced vibration by using the bionic nonsmooth surface structure has been successfully applied in bionic drag reduction technology [38][39][40]. Based on bionics and mechanicalelectric conversion mechanism, the concept of bionics is adopted for the design of bluff body in this paper.…”

Section: Physical and Mathematical Modelsmentioning

confidence: 99%

Design, Modeling, and Experiments of the Vortex-Induced Vibration Piezoelectric Energy Harvester with Bionic Attachments

Jin

Wang

et al. 2019

Complexity

View full text Add to dashboard Cite

Since the energy demand increases, the sources of fluid energy such as wind energy and marine energy have attracted widespread attention, especially vortex-induced vibrations excited by wind energy. It is well known that the lock-in effect in vortex-induced vibration can be applied to the piezoelectric energy harvester. Although numerous researches have been conducted on piezoelectric energy harvesting devices in recent years, a common problem of low bandwidth and harvesting efficiency still exists. In order to increase the response amplitude and decrease the threshold wind speed of vortex-induced vibration, a bionic attachment structure is proposed based on the experimental method. In the present work, twelve models are designed according to the size of pits and hemispheric protrusions which are added to the surface of a flexible smooth cylinder. Compared with the smooth cylinder which is taken as a carrier, the harvester with the bionic structure shows stronger energy capture performance on the whole. As the threshold speed decelerates from 1.8m/s to 1 m/s, the bandwidth, on the contrary, increases from 39.3% to 51.4%. Particularly, for the 10 mm pits structure with 5 columns, its peak voltage can reach 47 V, and its peak power can reach 1.21 mW with a resistance of 800 kΩ, 0.57 mW higher than that of the smooth cylinder. Comparatively speaking, the hemispherical projections structure figures with a much more different energy capturing characteristic. Starting from the column, the measured voltage of the hemispherical bionic harvester is much smaller than that of the smooth cylinder, with a peak voltage less than 15 V and a reducing bandwidth. However, compared with the smooth cylinder, hemispheric projections with 3 columns have a better energy capture effect with a measured voltage of 35V, a resistance of 800kΩ, and a wind speed of 3.097 m/s. Besides, its output power also enhances from 0.48 to 0.56 mW.

show abstract

Section: Physical and Mathematical Modelsmentioning

confidence: 99%

Design, Modeling, and Experiments of the Vortex-Induced Vibration Piezoelectric Energy Harvester with Bionic Attachments

Jin

Wang

et al. 2019

Complexity

View full text Add to dashboard Cite

show abstract

“…The bionic structure has a great influence on the near-surface flow characteristics. The drag reduction mechanism can be revealed by flow-field simulations (Gu et al, 2014;Mezghani, Demirci, Zahouani, & Mansori, 2012;Tian, Ren, & Liu, 2007). It was found that the bionic structure could reduce the flow velocity around the surface and change the vortex-induced vibration.…”

Section: Introductionmentioning

confidence: 99%

Research on the mechanism of drag reduction and efficiency improvement of hydraulic retarders with bionic non-smooth surface spoilers

Wei

Li³

et al. 2020

Engineering Applications of Computational Fluid Mechanics

View full text Add to dashboard Cite

Idling power loss suppression techniques of hydraulic retarders in non-braking operating conditions are of great significance to improve vehicle driving efficiency. Most proposed idling power loss suppression devices require auxiliary operating parts, take up a lot of space and increase the load on the vehicle. In this study, the plunger spoiler was optimized with a non-smooth bionic surface for improved performance and compactness. Hydraulic retarders with traditional smooth spoilers and different bionic non-smooth surface spoilers were simulated and tested to investigate the effects of bionic non-smooth surfaces on idling performance. The numerical results indicated that the bionic spoilers could disturb the fluid flow, lower the blade pressure and increase the internal energy dissipation, leading to reduced rotor drag and lower idling power loss. The mechanism of drag reduction on rotor and efficiency improvement was discussed. The experimental data showed that bionic nonsmooth surface spoilers reduced idling torque by 11.7% at a rotor speed of 3000 r/min, compared to the traditional smooth surface spoilers. In conclusion, the hydraulic retarder with an optimized bionic surface spoiler is able to reduce idling power loss and improve transmission efficiency effectively.

show abstract

“…There have been remarkable achievements in bionic applications in the engineering and mechanical manufacturing fields. 9,10 For example, the frictional force using the bionic dimple structure can be reduced by as much as 7%-10% in laboratory experiments. A bionic V-riblet structure has been shown to reduce 1%-2% drag force in airplane flight tests.…”

Section: Introductionmentioning

confidence: 99%

Numerical investigation of passive control flow to improve tire hydroplaning performance using a V-riblet non-smooth surface

Zhou

Zhai²,

Ding

et al. 2017

Advances in Mechanical Engineering

View full text Add to dashboard Cite

As one of the major causes of traffic accidents, tire hydroplaning is a key driver safety concern. A tire model 205/55R16 was employed in this study, and a virtual simulation of a deformed half-tire domain for calculating hydroplaning speed was built by virtue of computational fluid dynamics. Water-flow field characteristics were simulated using gas-liquid twophase flow. The simulated tire hydroplaning speed is in accord with the measured tire hydroplaning data. Guided by the idea that the drag-reduction effect of the V-riblets based on bionic study of shark skin, effects of V-riblet bionic nonsmooth surface parameters on water displacement, and flow resistance were analyzed to improve tire tread pattern draining capacity. The water drag-reduction mechanism was declared by the vortex vector and speed field, and the optimal V-riblet surface for drag reduction was set on the bottom circumferential grooves to analyze hydroplaning speed. The results demonstrate that the V-riblet bionic non-smooth surface can effectively decrease tread hydrodynamic pressure when driving on a water-film and increase tire hydroplaning speed.

show abstract

Experimental and numerical investigation on drag reduction of non-smooth bionic jet surface

Cited by 48 publications

References 25 publications

Design, Modeling, and Experiments of the Vortex-Induced Vibration Piezoelectric Energy Harvester with Bionic Attachments

Design, Modeling, and Experiments of the Vortex-Induced Vibration Piezoelectric Energy Harvester with Bionic Attachments

Research on the mechanism of drag reduction and efficiency improvement of hydraulic retarders with bionic non-smooth surface spoilers

Numerical investigation of passive control flow to improve tire hydroplaning performance using a V-riblet non-smooth surface

Contact Info

Product

Resources

About