Browsing by Author "Wang, Sheng-Yan"

Now showing 1 - 3 of 3

CHARACTERISTICS OF ELECTROMAGNETIC INDUCTION BY MOVING FERROFLUIDS
(2012-07-01)
Chen, Ching-Yao
;
Wang, Sheng-Yan
;
Wu, Chi-Ming
;
Lin, Chung-Hao
;
Huang, Kuo-An
We have demonstrated the capabilities to catch the signals of induced electromotive force (EMF). The characteristics of EMF signals are analyzed systematically. Influences of volumes, sizes and travelling velocities of ferrofluids on the magnitudes and wave spans of the signals are presented. In addition, simulations of the induction fields are carried out to provide the physical insights of the induced EMF signals. The signals can be potentially applied as diagnostic characteristics in the measurements of travelling velocities or sizes of moving ferrofluid drops or slugs.
EFFECT OF SIZE AND STRETCH OF A MOVING FERROFLUID DROP ON INDUCED ELECTROMOTIVE FORCE
(2016-07-09)
Chen, Ching-Yao
;
Wang, Sheng-Yan
;
Wen, Chih-Yung
;
Jan, Cheng-Shiung
;
機械工程學系
Application for obtaining useful global features, e.g. the size and stretch of a moving ferrofluid drop by analyzing the characteristics of the induced electromotive force signal is demonstrated. These features are highly relevant to two maximum magnitudes in the electromotive force signal, e.g., the positive (V-1) and the negative (V-2) peak respectively induced when the drop enters and leaves the region covered by the induction coil. Favorable induction conditions of these two maximum magnitudes are opposite. In general, V-1 increases with the size of the ferrofluid drop because of stronger magnetization. On the contrary, V-2 is more prominent for a smaller drop, whose stretch is less significant. As a result, the ratio of vertical bar V-1/V-2 vertical bar monotonically increases with the, size of the ferrofluid drop. This finding suggests that the induced EMF signal can be used as a useful tool for quantifying the flow conditions, such as the size and stretch of moving ferrofluids.
Self-assembly and novel planetary motion of ferrofluid drops in a rotational magnetic field
(2015-05-01)
Chen, Ching-Yao
;
Hsueh, Hao-Chung
;
Wang, Sheng-Yan
;
Li, Yan-Hom
;
機械工程學系
We experimentally investigate the motion of a ferrodrop array in a rotating magnetic field. Magnetized and driven by the external field, the ferrodrops are stretched and self-aligned to form a drop array along the field orientation. An interesting planet-like dual rotation, including local self-spins of individual drops and a global revolution of the drop array, is newly identified. While the drops spin nearly synchronized with the external field, the revolution always lags behind the field and appears a forth and back movement. Prominence of the net revolutionary movement depends on the strength and uniformity of the overall field as well as the number of drops containing in the array. In general, more uniform and stronger rotating field leads to a more prominent global revolution. Phenomenon of such planetary motion can be applied to mix two fluids more effectively than self-spin drops.