Signal Analysis And Development Of Strain Measuring For Torsional Vribration Of Ship Shafting

With the "Belt and Road" policy raising up,the demand of building a global interest community and a destiny community are constantly deepening,and the increasing of global trade exchanges has brought new opportunities for the development of the shipping businesses.At the same time,it also puts forward more stringent requirements for the shipping industry that undertakes major transportation tasks.Currently,the indicators of the ship owners which are focused on when receiving a new vessel concentrate mainly on rapid navigation,safety,efficient loading and unloading of cargo,life and work comfort of the crew,and economy of ship operations.Ship power system is one of the key factors which can influence the above ship performance.The torsional vibration of shafting,as the main form of power system,has been closely watched.The study of torsional vibration is closely related to the continuous improvement of signal test technique and signal processing analysis method.Ship power system is one of the key factors influencing the above ship performance.The torsional vibration of shafting,as the main way to influence the ship power system,has been closely watched.The study of torsional vibration is closely related to the continuous improvement of signal test technique and signal processing analysis method.In order to make accurate judgments on the reliability of the propulsion shaft system in torsional vibration,it is necessary to rely on the actual measurements of the torsional vibration.In addition,many experts,which are at home and abroad,use the crankshaft instantaneous speed and torsional vibration signals for fault diagnosis.It also needs to accurately measure the crankshaft torsional vibration and instantaneous speed.On the basis of previous study,this paper studies the problems in torsional vibration test,mainly including:In order to ensure the accuracy of the torsional vibration and the accuracy of the test,the influence of the tooth number and the frequency of the data acquisition on the test results is researched.The upper,lower and lowest data acquisition frequencies of the gear teeth per turn are deduced.And the calculation formula of the upper,lower and lowest numerical frequencies of the tooth number of each revolution tooth number is deduced.Combined with simulation and experiment,this paper analyzes the concrete influence of the joint clearance on the torsional vibration test,and gives the correction plan,and improves the precision of the torsional vibration result by using the split tooth.In order to improve the test efficiency and test accuracy of the torsional vibration of the shaft system,the method and flow of the torsional vibration measurement by the strain method are studied.At the same time,the time-domain statistical analysis,the primary harmonic analysis based on correlation analysis,and the weight analysis of the influencing factors of torsional vibration based on the energy characteristics of wavelet packet frequency band are performed for the data obtained from the variable method test,providing methods and basis for the analysis of test results and feedback theoretical calculations.Based on the Visual Basic.NET language,to facilitate the processing and analysis of test results,through the mixed programming of Visual Studio and MATLAB,A set of shafting torsional vibration test and analysis software with full independent intellectual property rights is developed to meet the actual needs of the industry.Moreover,the 5000 HP tugboat is used as an example to test the software..It is proved by that result of the software test that the analysis method of the software is reliable,the program is correct,the software is simple and functional,and it can meet the requirement of the analysis of the strain of shafting in the industry.