| Since the 18 th National Congress of the Chinese Communist Party,China attaches unprecedented importance to the exploitation of ocean resources.Therefore,the demand for ocean environmental monitoring is increasing.Various ocean environment monitoring methods have covered most sea areas in China,among which buoy monitoring is the most widely used ocean environment monitoring method.However,the Bohai sea and the North Yellow Sea are seasonally frozen sea areas.Ordinary ocean monitoring buoys are vulnerable to sea ice damage in winter and cannot operate safely and sustainably in these areas.This situation has resulted in the serious loss of monitoring data series,which has greatly hindered the development of marine undertakings.So,it is urgent to carry out the anti-ice design and research of small ocean monitoring buoys to effectively guarantee the spatio-temporal continuity of marine environmental monitoring data series.Firstly,by investigating the development and structural characteristics of small buoys at home and abroad,this paper summarizes the failure modes of common ocean monitoring buoys in seasonally frozen sea areas.By referring to the ice-resistant design method of general marine structures in cold regions and combining with the knowledge of floating body statics and ice mechanics,it proposes the design theory of ice-resistant buoy structure and mooring system based on reserve buoyancy.It analyzes the influence of different parameters(maximum diameter,sidewall angle,mooring length,etc.)on the ice resistance of buoys.It is found that increasing the maximum diameter and side wall Angle and properly increasing the mooring length can effectively improve the ice resistance of buoy structure.In order to ensure that the anti-ice buoy can meet the performance of ordinary buoys in the normal floating state,Maxsurf software and AQWA software are used for checking.During the test,the iceresistant buoy withstood severe ocean environment such as strong wind waves and severe sea ice,and successfully collected and effectively transmitted relevant data in real time.Based on the analysis of a large number of measured data,it clarifies the motion variation law of buoys and the destruction process of sea ice during ice breaking,and it proposes a simplified ice force time history model of small floating body.The function fitting relationship between the ice force action time coefficient and the ice-breaking period is obtained,which provides a theoretical basis for the numerical simulation of dynamic response of buoys under the action of sea ice.Finally,the dynamic response characteristics of ice-resistant buoys are analyzed based on numerical simulation,and compared with the measured data.AQWA software is used to simulate the rolling motion response of the buoy under the action of conventional wind and wave flow,and the simulation results are in good agreement with the measured data.Based on the dynamic ice load model of small floating body,the dynamic response of buoys under characteristic ice conditions was simulated and compared with the measured results.It is found that the general law of the two is roughly similar,and then the reasons for the difference are discussed.The maximum mooring tension of buoy mooring system in conventional wave and sea ice environment is simulated and compared.The force characteristics of the mooring system can be used as a reference for the design of the mooring system of small ice-resistant floating body.In this paper,by means of theoretical analysis,prototype test and numerical simulation,an exploratory study is made on the ice resistance design theory system of small floating body structure.It can not only promote the development of Marine environmental monitoring,but also provide theoretical support for the design and application of small and medium-sized floating anti-ice equipment in polar regions. |
