Study On The Noise Of The Jack-up Platform’s Living Cabin With Statistical Energy Analysis

With the increasing demand of oil resources, the offshore oil development has become the focus of attention. Since the offshore platform is an important tool for marine resources exploitation, the safety and comfort of it cannot be ignored. The noise not only affects people’s work, study and rest, but also affects the health of the human body directly. IMO requires new boats and existing ships to perform the noise standards specified in IMO A468(XII). Nowadays, some EU countries have even proposed to reduce5dB on the basis of original criteria. So it’s quite necessary to predict and control the noise of the cabin.In the present thesis the noise of a jack-up platform living cabin is analyzed, and the main contents are shown as follows:Firstly, the development and the basic theory of the Statistical Energy Analysis method is described, and the system’s energy balance equation is analyzed and the general expression of the energy balance equation is given. Then the determination of the statistical energy parameters which are key to the application of the statistical energy analysis method research and the solution of the problem are pointed out (damping loss factor, coupling loss factor, modal number, modal density, input power, etc).Secondly, the whole frequency noise analysis software VA One is briefly introduced and the basic process in modeling of SEA module is discussed in the present thesis. In addition, the platform of SEA model is established according to the drawings, and some experience and skills of modeling are summarized.Thirdly, the research on the noise level of the diesel generator which is the main noise source is carried out. And the sound pressure level is estimated by the aid of the empirical formula. What is more, the diesel generator is loaded into the statistical energy analysis model as an excitation. Some important parameters and the cabin sound pressure level are figured out by solving the model and the reasons leading to of errors are analyzed.Finally, the general principles and methods of the noise control are discussed. These methods can be applied for the cabins on the platform decks that do not meet the regulatory requirements to reduce noise. Besides, the corresponding solutions are given and the references for noise control of the platform are provided.The present thesis is the noise part of the special project "Study on the Vibration and Noise of the Platform", and it was supported by the national high technology research and development (863) program "Design and Technology of the300Feet Jack-up Drilling Platform ".And this is of guiding significance and reference value for the reduction of the vibration and noise of the platform.