Picture of boy being examining by doctor at a tuberculosis sanatorium

Understanding our future through Open Access research about our past...

Strathprints makes available scholarly Open Access content by researchers in the Centre for the Social History of Health & Healthcare (CSHHH), based within the School of Humanities, and considered Scotland's leading centre for the history of health and medicine.

Research at CSHHH explores the modern world since 1800 in locations as diverse as the UK, Asia, Africa, North America, and Europe. Areas of specialism include contraception and sexuality; family health and medical services; occupational health and medicine; disability; the history of psychiatry; conflict and warfare; and, drugs, pharmaceuticals and intoxicants.

Explore the Open Access research of the Centre for the Social History of Health and Healthcare. Or explore all of Strathclyde's Open Access research...

Image: Heart of England NHS Foundation Trust. Wellcome Collection - CC-BY.

How motion trajectory affects energy extraction performance of a biomimic energy generator with an oscillating foil?

Xiao, Qing and Liao, Wei and Yang, Shuchi and Peng, Yan (2012) How motion trajectory affects energy extraction performance of a biomimic energy generator with an oscillating foil? Renewable Energy, 37 (1). pp. 61-75. ISSN 0960-1481

Full text not available in this repository. Request a copy from the Strathclyde author

Abstract

A non-sinusoidal trajectory profile is proposed for the oscillating hydrofoil in the energy generators instead of conventional sinusoidal plunging/pitching motions to seek better energy extraction performance. The novel profile is achieved by combining a specially designed trapezoidal-like pitching motion with a sinusoidal plunging motion and investigated numerically on its output energy coefficient and total output efficiency. Through an adjustable parameter b, the pitching profile can be altered from a sinusoidal (b ¼ 1.0) to a square wave (b / N). In this work, a series of b ranging from 1.0 to 4.0 are investigated to examine the effect of combined motion trajectory on the energy extraction performance. The study encompasses the Strouhal numbers (St) from 0.05 to 0.5, nominal effective angle of attacks a0 of 10 and 20 and plunging amplitude h0/c of 0.5 and 1.0. Numerical results show that, for different b pitching motions, a larger a0 always results in a higher extraction power Cop and total efficiency hT. Compared with the sinusoidal motion (b ¼ 1), significant increment of Cop and hT can be observed for b > 1 over a certain range of St. The investigation also shows that there exists an optimal pitching profile which may increase the output power coefficient and total output efficiency as high as 63% and 50%, respectively, over a wide range of St. Detailed examination on the computed results reveal that, the energy extraction performance is determined by the relative ratio of the positive and negative contributions from the different combination of lift force, momentum and corresponding plunging velocity and pitching angular velocity, all of which are considerably affected by b.