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The ultra-high-speed aerodynamically alleviated marine vehicle (AAMV) is a high-performance vessel that combines a hydrodynamic configuration and an aerodynamic wing to reduce wave-making resistance during the high-speed planing phase. The forces of the AAMV exhibit strong nonlinear and water–air coupling characteristics, resulting in particularly complex motion characteristics. This paper presents a longitudinal and lateral stability model of the AAMV, which considers the effects of aerodynamic alleviation. Additionally, a numerical model of wind and wave turbulence forces is established, which considers viscous correction based on the potential theory. Finally, the effect of wind and wave turbulence forces on the motion stability of the AAMV under regular and irregular waves is analyzed by numerical solution. The simulation results demonstrate the influence of these disturbance forces on the stability of the AAMV under different sea states. The motion parameters of the AAMV exhibit a pronounced response to changes in sea state level. The aerodynamically alleviated effect is enhanced as speed increases, and the influence of winds and waves on the AAMV is greatly weakened, reducing the possibility of instability. During the cruising phase under class V sea state, the pitch, roll, and heave response are 0.210°, 0.0229°, and 0.0734 m, respectively. This effect can effectively improve the motion stability of the AAMV in winds and waves. [ABSTRACT FROM AUTHOR]

The ultra-high-speed aerodynamically alleviated marine vehicle (AAMV) is a high-performance vessel that combines a hydrodynamic configuration and an aerodynamic wing to reduce wave-making resistance during the high-speed planing phase. The forces of the AAMV exhibit strong nonlinear and water–air coupling characteristics, resulting in particularly complex motion characteristics. This paper presents a longitudinal and lateral stability model of the AAMV, which considers the effects of aerodynamic alleviation. Additionally, a numerical model of wind and wave turbulence forces is established, which considers viscous correction based on the potential theory. Finally, the effect of wind and wave turbulence forces on the motion stability of the AAMV under regular and irregular waves is analyzed by numerical solution. The simulation results demonstrate the influence of these disturbance forces on the stability of the AAMV under different sea states. The motion parameters of the AAMV exhibit a pronounced response to changes in sea state level. The aerodynamically alleviated effect is enhanced as speed increases, and the influence of winds and waves on the AAMV is greatly weakened, reducing the possibility of instability. During the cruising phase under class V sea state, the pitch, roll, and heave response are 0.210°, 0.0229°, and 0.0734 m, respectively. This effect can effectively improve the motion stability of the AAMV in winds and waves.

The inefficient cleanup of viscous heavy oil is thought as a worldwide problem because of its poorer fluidity at room temperature. Herein, we make full use of the photothermal performance to harvest solar energy and convert heat into heavy oil, thus reducing significantly oil viscosity and realizing rapid oil remediation. Specially, the polydopamine as photothermal components, titanium dioxide and perfluorodecyltrichlorosilane as superhydrophobic/superoleophilic source are introduced into the melamine-formaldehyde sponge by deposition method. To be applicable in the marine environments with winds and waves, the bottom side of this sponge subjected to UV irradiation is transferrable from superhydrophobicity to superhydrophilicity. The Janus sponge can keep the balance of movement and never overturned under the action of wind force, thereby enabling this sponge to absorb consecutively spilled heavy oil from marine system. With one simulated solar irradiation, the top and bottom of Janus sponge are heated to a suitable temperature of 90.7 and 70.2 °C, respectively. Relied on these advantages, the Janus sponge can effectively reduce the viscosity of spilled heavy oil and enhance its fluidity, which allow for quick heavy oil absorption up to nearly 12 times of own weight. Meanwhile, it can be also compressed for recycled uses.

In this study, loads on a 1:10-scaled coastal bridge deck model were experimentally investigated under the combined action of extreme winds and waves. The loads and hydrodynamic pressure with respect to different clearances, incident wave heights, wave periods, and wind velocities were analyzed. The experimental results revealed that the wind effects were crucial for the determination of loads on bridges during hurricanes. In small-wave-height cases, both the vertical and horizontal forces were enhanced under the combined action. Furthermore, the vertical quasi-static force comprised an additional peak in high-wind-velocity cases. This peak was due to the wind pressure differences on the deck. The falling water and traveling waves had blocking effects on the wind, resulting in positive up wind forces. In large-wave-height cases, the horizontal force was restrained by the wind action. As the wave height increased, the vertical force was also restrained by the wind action until overtopping waves occurred. The results of the pressure at different locations showed that the wind action could enhance the vertical force by increasing the pressure at the rear of the deck. A quadrant analysis showed that extreme winds could significantly increase the combined load at the dangerous state of the bridge deck. • Loads on bridge are experimentally studied under the combined action of wind and waves. • The vertical quasi-static force comprises an additional peak in high-wind-speed case. • The effect of extreme wind on horizontal and vertical loads on bridge deck are given. [ABSTRACT FROM AUTHOR]

The inefficient cleanup of viscous heavy oil is thought as a worldwide problem because of its poorer fluidity at room temperature. Herein, we make full use of the photothermal performance to harvest solar energy and convert heat into heavy oil, thus reducing significantly oil viscosity and realizing rapid oil remediation. Specially, the polydopamine as photothermal components, titanium dioxide and perfluorodecyltrichlorosilane as superhydrophobic/superoleophilic source are introduced into the melamine-formaldehyde sponge by deposition method. To be applicable in the marine environments with winds and waves, the bottom side of this sponge subjected to UV irradiation is transferrable from superhydrophobicity to superhydrophilicity. The Janus sponge can keep the balance of movement and never overturned under the action of wind force, thereby enabling this sponge to absorb consecutively spilled heavy oil from marine system. With one simulated solar irradiation, the top and bottom of Janus sponge are heated to a suitable temperature of 90.7 and 70.2 °C, respectively. Relied on these advantages, the Janus sponge can effectively reduce the viscosity of spilled heavy oil and enhance its fluidity, which allow for quick heavy oil absorption up to nearly 12 times of own weight. Meanwhile, it can be also compressed for recycled uses. Unlabelled Image • The Janus sponge was successfully synthesized by successive deposition and final UV irradiation. • The Janus sponge exhibited five superhydrophobic sides and a superhydrophilic bottom side. • This Janus sponge exhibited excellent mechanical property at a strain of 80% and 50 cyclic compression tests. • The Janus sponge could keep excellent floating stability for 20 s or more under marine conditions with winds and waves. • The Janus sponge could absorb stably viscous heavy oil by photothermal effect, with absorption capacity to 11.2 g/g. [ABSTRACT FROM AUTHOR]