Marine diesel engine thermal parameter estimation method for working condition switching

Abstract

A working condition switching-oriented marine diesel engine thermal parameter estimation method belongs to the field of marine diesel engine thermal parameter identification and comprises the following steps: under different working conditions, acquiring and preprocessing thermal parameters such as rotating speed, exhaust temperature and power in the working process of a diesel engine bench experiment table; respectively analyzing a relation curve between the three variables of the rotating speed, the exhaust temperature and the power and the load working condition through polynomial fitting, giving a fitting curve effect picture, and evaluating a fitting effect through an average absolute percentage error (MAPE); then, the relation between the three variables of the rotating speed, the exhaust temperature and the power and the propulsion working condition is analyzed through polynomial fitting, a fitting curve graph is given, the fitting effect is evaluated through the MAPE index, and therefore accurate estimation of the thermal parameters of the marine diesel engine under the condition that the multiple working conditions change is achieved. The working condition switching-oriented marine diesel engine thermal parameter estimation method provided by the invention can improve the accuracy of parameter estimation, is more in line with the actual working condition of the marine diesel engine, can be effectively applied to the scene of frequent actual working condition switching, and meanwhile, can improve the working condition switching-oriented marine diesel engine thermal parameter estimation accuracy. By adopting a polynomial fitting mode, final model parameters can be reduced, the complexity of the model is reduced, and the calculation efficiency is improved. Finally, the thermal parameter estimation method under common working conditions can be expanded to estimation of thermal parameters under any working conditions, and the expansibility and practicability of the method are high.

Description

technical field [0001] The invention belongs to the field of thermal parameter identification of marine diesel engines, and relates to a method for estimating thermal parameters of marine diesel engines for working condition switching. Background technique [0002] Among all kinds of power equipment, diesel engine is widely used in the shipping industry due to its advantages of high thermal efficiency, good economy and strong adaptability, and it is the power source and heart of the ship in flight. In recent years, marine diesel engines have gradually developed into the most commonly used marine power devices in the world. Among the existing large and medium-sized civil ships, more than 90% use diesel engines as main propulsion devices, and only in some individual special fields also use internal combustion engines, steam engine etc. Because the working process of diesel engine is complex, there are many influencing factors, and a large number of thermal parameters are prod...

AI Technical Summary

Problems solved by technology

[0004] The present invention is dedicated to solving the problem of estimating the main thermal parameters such as rotational speed, exhaust temperature and power when the working conditions of marine diesel engines are changed.

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