A Simulation Analysis Of A Passive Heave Compensator For Scientific Research Ships

Research vessels are commonly used for research,exploration,lowering and lifting of equipment,and payload handling among a few of the multiple task executed on a daily bases.However,due to unpredictable wave motion on the ship and the flexibility of the cable,the resulting heave of the ship is unavoidable and causes danger during operations to human life,reduce operational time,loss of payload and damages to equipment.A heave compensator system is an essential part of operations in-order to ensure safety,avoid down-time and increase work efficiency during normal operational time.In this thesis,a passive heave compensator system with cylinder,accumulator,depth compensator connected in series with pressured pipes is presented and the efficiency to apply in the real world is analyzed by software.The main objective of this thesis is to demonstrate the positive effects of a type of passive heave compensator during payload handling or lifting operations for scientific research vessels or small vessels in general.The passive heave compensator model analyzed in this research was presented in a patent by Matthew Jake Ormond,2011.This model has been modified to obtain all the results presented in this thesis.The working principle of the heave compensation system is described;the main and sub parameters of the system are calculated.The parameters which affect the performance of the system are simulated and analyzed by MATLAB.The results show that the satisfactory control effectiveness can be obtained under sea condition 4.The compensation rate of the system is higher than 77%under the influence of the input wave condition and has a response of an average setting time of 20s.The wave force was calculated using amplitude of 1 meter and wave period of 6 seconds.The compensator is feasible for real world application.Software incorporated in this thesis in fulfillment of the aim and objectives are MatLab,AutoCAD,SolidWorks and Microsoft Excel.The objective of the thesis has been reached and the results are presented in this thesis.