In this article, to meet the requirements of marine engine room simulator on both the simulation speed and simulation accuracy, a mean value engine model (MVEM) for the 7S80ME-C9.2 marine two-stroke diesel engine was developed and validated in the MATLAB/Simulink environment. In consideration of the significant influence of turbocharger compressor on both the engine steady state performance and transient response, a novel compressor model (mass flow rate and isentropic efficiency model) based on a previous study carried out by the first author was proposed with the aim of achieving satisfactory simulation accuracy within the whole engine operating envelope. The predictive and extrapolative capability of the proposed compressor model was validated by carrying out simulation experiments and analyzing the simulation results under steady state condition and during transient process. To make the traditional MVEM capable of predicting in-cylinder pressure trace, the cylinder pressure analytic model proposed by Eriksson and Andersson for the four-stroke SI (spark ignition) engine was adapted to the 7S80ME-C9.2 marine two-stroke diesel engine based on the characteristic of in-cylinder pressure trace of this type of engine and then coupled to the MVEM developed in this paper. Since there is no need to solve any differential equation as it is done in the 0-D model, the advantage of MVEM in running speed is not impaired. For achieving satisfactory simulation accuracy by using the analytic model, the model parameters were calibrated elaborately by using engine measured data and a 0-D model and the relevant tuning procedure was discussed in detail.

A compressor is an indispensable component of marine large two-stroke diesel engines. For this type of engine, the compressor mass flow rate and isentropic efficiency empirical models are preferred for both the working cycle dynamic simulation research and the design and testing of control and diagnostics algorithms due to their compact and simple structures, and satisfactory prediction accuracy. Due to absence of comprehensive applicable and comparative research on compressor mass flow rate and isentropic efficiency empirical models for large-scale marine compressors in the literature, two marine compressors with different size, flow rate range, and speed range were selected as research objects in this paper, and a relevant study was conducted to compare and analyze the prediction ability of several classical models, and some recently proposed compressor mass flow rate and isentropic efficiency empirical models. The range of this comparative study includes the prediction accuracy in the design operating area and the extrapolation ability in off-design operating areas. Based on the obtained research results, several guidelines are summarized, which can be followed when developing compressor mathematical models, especially for marine applications. In addition, several research interests are discussed and presented, which can be further studied in the future.

Yang, B.; Zhao, Z., and Zheng, G., 2020. The relevance analysis of regulation clarity degree and human error contribution to ship collision accidents. In: Yang, D.F. and Wang, H. (eds.), Recent Advances in Marine Geology and Environmental Oceanography. Journal of Coastal Research, Special Issue No. 108, pp. 32–36. Coconut Creek (Florida), ISSN 0749-0208.Analyzed in this paper is the correlation between the risk degree of the human risk factor in collision accidents at sea and the clarity degree of regulations related to the risk factor. The risk degree of each factor is analyzed based on the fuzzy rule-based Fine-Kinney method. The defuzzification contribution value of each risk factor to collision accidents is obtained. The confidence value in a priori algorithms of each human risk factor in accidents is obtained by mining the data of 481 accidents in the Liaoning sea area from 2005 to 2014. Nine experts score the clarity degree of the management regulations which are relevant to each risk factor. And the Analytic Hierarchy Process (AHP) weight value of each factor's clarity is calculated by the AHP. The AHP weight values cannot express the clarity degree, but they are approximately equal to one in a million of evaluation scores in the Fine-Kinney method whose score can express the clarity degree. Then the AHP weight values, instead of Fine-Kinney scores of the clarity degrees, are compared with the fuzzy rule-based Fine-Kinney defuzzification contribution values and the a priori algorithm confidence values of the human risk factors in collisions, respectively. The AHP weight values are a negative linear correlation with the defuzzification values and confidence values. This demonstrates that the more clarified the relevant regulations are, the lower the risk of the human factor in ship collision avoidance operation will be.

A high-speed advancing ship will cause significant squats in shallow water, which could increase the risk of grounding. To this end, a program based on the Rankine higher-order boundary element method (HOBEM) is developed to investigate a high-speed displacement ship with a transom stern moving in shallow water. The nonlinear free surface condition is satisfied by adopting an iterative algorithm on the real free surface. The transom condition is considered by implementing a modified transom condition. Computations of wave-making resistance, sinkage and trim in deep water are first performed, and satisfactory agreement is achieved by comparing with the experimental results; the simulations are then extended to the shallow water case. It indicates that the present method can provide a suitable balance of practicability and robustness, which can be considered as an efficient tool for the guidance in ship design stage.