Kolahdoozan, M.; Bali, M.; Rezaee, M., and Moeini, M.H., 2017. Wave-transmission prediction of π-type floating breakwaters in intermediate waters. Floating breakwaters (FBs) are distinguished as an ...environmentally friendly type of breakwater that are more deployed in the development of small ports. Dissipation and reflection are the main mechanisms by which FBs protect the leeward side; however, because of the structure geometry, a portion of the incident wave energy is transmitted to the shoreline. Thus, the transmission coefficient (Ct), which stands for the transmitted portion of wave energy in comparison with the total wave energy, is an important parameter that describes the structure's efficiency. Only a limited number of studies have been performed for the description of wave energy that is transmitted in the intermediate waters; therefore, in this study, an attempt has been made to present a proposed formula for the prediction of Ct in intermediate waters. The proposed formula is based on the experimental measurements performed in the current study. The proposed formula was also evaluated using extra data. The correlation coefficients of 0.75 and 0.69 for the data set of this study and extra data from previous studies revealed that the proposed formula is more accurate than the previous formula provided for shallow and intermediate waters.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Up-welling and down-welling are formed in the inner and outer banks of the river bends, respectively. In this paper, a 3D numerical model is employed in order to study the effective parameters on the ...maximum value of the up-welling (
w
U(max)
) and down-welling (
w
D(max)
) in rectangular channel bends. A numerical model validated by the existing experimental data is applied to investigate the effects of different parameters on
w
U(max)
and
w
D(max)
over a wide range of flow conditions. The results revealed that the relative depth (water depth/bend radius) and bed resistance are the most effective parameters on
w
U(max)
and
w
D(max)
, with a direct relationship. Moreover, based on the numerical results, two formulas are proposed for prediction of
w
U(max)
and
w
D(max)
. Accuracy metrics such as root-mean-square error, bias and correlation coefficient indicated that the developed formulas can be applied successfully to approximate
w
U(max)
and
w
D(max)
for engineering application.
Stability formulae for armour layers of rubble mound breakwaters are generally developed for perpendicular wave attack and do not include effects of oblique waves. Waves usually attack breakwater ...obliquely as the sea wave is three dimensional. Several studies have been performed to investigate the effect of wave angle (beta) on the armor stability. Galland (1994), Yu et al. (2002), Wolters and Van Gent (2010) and van Gent (2014) performed laboratory experiments to consider effects of oblique waves on the stability of armour layers. They performed tests with long-crested and/or short-crested waves on rock and concrete armours. The aim of this study is to find an appropriate and compatible reduction factor for EBV stability formulae.
