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In order to obtain information regarding changes in the air cushion flow field and load-bearing characteristics of a single row hole air cushion belt conveyor, a structural model of the air cushion of the belt conveyor was established, with the single row hole air cushion belt conveyor as the research object. Firstly, according to the theory of fluid lubrication, a mathematical model of the air cushion was established. Then, the effects of air cushion thickness, pore velocity, and belt velocity on the pressure and bearing characteristics of the air cushion flow field were studied using FLUENT software. In addition, the equivalent stress, displacement, and pressure curves between the air cushion flow field and the conveyor belt and the material were analyzed using the two-way fluid–solid coupling method. Finally, the experimental platform of a single row hole air cushion belt conveyor was built, and the flow field and bearing characteristics of the belt were verified through experiments. The results show that reducing the thickness of the air cushion and increasing the pore flow rate can improve the pressure and bearing characteristics of the air cushion, while speed has little effect at lower belt speeds. [ABSTRACT FROM AUTHOR]

In order to obtain information regarding changes in the air cushion flow field and load-bearing characteristics of a single row hole air cushion belt conveyor, a structural model of the air cushion of the belt conveyor was established, with the single row hole air cushion belt conveyor as the research object. Firstly, according to the theory of fluid lubrication, a mathematical model of the air cushion was established. Then, the effects of air cushion thickness, pore velocity, and belt velocity on the pressure and bearing characteristics of the air cushion flow field were studied using FLUENT software. In addition, the equivalent stress, displacement, and pressure curves between the air cushion flow field and the conveyor belt and the material were analyzed using the two-way fluid–solid coupling method. Finally, the experimental platform of a single row hole air cushion belt conveyor was built, and the flow field and bearing characteristics of the belt were verified through experiments. The results show that reducing the thickness of the air cushion and increasing the pore flow rate can improve the pressure and bearing characteristics of the air cushion, while speed has little effect at lower belt speeds.

Aiming at the non-uniformity of the air film between the conveyor belt and the trough during the operation of the air-cushion belt conveyor, a comprehensive study was executed by means of simulation analysis. Firstly, the air cushion pressure was theoretically deduced according to the principle of force balance, and the theoretical distribution expression and curve of air cushion pressure were given. Then, by constructing a gas flow model around the stomata, the pressure and velocity distribution of the flow field near the stomata were deduced, by constructing a cross-sectional gas outflow model, the outflow velocity and pressure distribution of the air cushion along the cross-section were deduced. Finally, the air cushion field was simulated and analyzed based on the fluid dynamics analysis software Fluent, the effects of different pore velocity, pore arrangement and air cushion thickness on the characteristics of the air cushion flow field were studied. The results indicate that air cushion pressure decreases with increasing air cushion thickness. The bearing capacity of the air cushion has a linear relationship with the stomatal flow rate, and the linear ratio is K=41.57. The optimal design parameters for the arrangement of air holes is the aperture of 7 mm and the hole spacing of 75 mm. When the air cushion thickness is 3 mm ～5 mm, air cushion stiffness decreases with increasing air cushion thickness. [ABSTRACT FROM AUTHOR]

The partial air cushion supported catamaran (PACSCAT) is a novel Surface Effect Ship (SES) and possesses distinctive resistance performance due to the presence of planing bottom. In this paper, the design of PACSCAT and air cushion system are described in detail. Model tests were carried out for Froude numbers ranging from 0.1 to 1.11, the focus is on the influence of air cushion system on resistance characteristics. Drag-reducing effect of air cushion system was proved by means of contrast tests in cuhionborne and non-cushionborne mode. Wave-making characteristics reflect that the PACSCAT would eventually enter planing regime, in which the air could just escape under the seals and the hull body could operate in a steady state. To acquire different air cushion pressure, air flow rate and leakage height were adjusted during tests. Experimental results show that the resistance performance in planing regime would decrease evidently as the increased air flow rate, however, the scheme with medium leakage height presents the best resistance performance in the hump region.

This paper investigates the cushion lift dynamics of a polar hovercraft. The motion of the flexible skirt on the ice surface is simplified and a mathematical model is established to study the dynamic response characteristics of the hovercraft in the process of lifting and moving over ice. This model considers the pressure/flow characteristics, skirt pressure, air cushion pressure, and flow rate of the fan of the hovercraft, and establishes a simulation using a C++program. When the hovercraft is pushed by the propeller, a thrust of 10 kN will cause a pressure difference of about 450 Pa between the front and rear chambers, 0.06 m in the height of the upstream and downstream discharge flows, and a decrease of about 0.4° in the longitudinal inclination angle. Changing the pitch angle to 0.5° creates a pressure difference of about 500 Pa between the chambers and a height difference of 0.07 m between the discharge. When the hovercraft speed is low, the wind speed has a small impact on the air cushion pressure of the lift system. The results of this research provide important technical and experimental foundations for further studies on the ice surface kinematics and safety control strategy of polar hovercraft. • A cushion lift dynamics system of a polar hovercraft by flow balance equation. • The model studies air cushion pressure changes through the discharge height. • Air cushion pressure in the air chamber is affected by external influence. • The hovercraft tests on the ice proves the effectiveness of the simulation results. [ABSTRACT FROM AUTHOR]