Effective thermal efficiency prediction method for marine diesel engine based on fuel component

Abstract

The invention aims to provide an effective thermal efficiency prediction method for a marine diesel engine based on fuel components. The method comprises the following steps: determining boundary conditions and initial conditions, selecting the type of fuel for combustion, dividing the working process in a cylinder into three stages of compression, combustion and expansion, calculating the compression process, the combustion process and the expansion process, conducting integral calculation on the obtained pressure, solving the effective work in the working process, and then solving the effective heat efficiency according to the ratio of the effective work to the total input heat. Effective thermal efficiency prediction of any constant-volume combustion ratio can be realized, so that the application range of the model is not limited to specific types of diesel engines. The method can predict the effective thermal efficiency of the diesel engine when different kinds of fuel are combusted, adapts to the development trend of the alternative fuel of the marine diesel engine at present, and provides a numerical prediction means for the thermal efficiency optimization design of the diesel engine in a wider range.

Description

technical field [0001] The invention relates to a thermal efficiency prediction method, in particular to a marine diesel engine thermal efficiency prediction method. Background technique [0002] With the increasing calls for energy saving and emission reduction in the society, various emission regulations for the shipping industry have been continuously proposed, and requirements for the control of various emissions from marine diesel engines have been put forward. Among the many emissions, carbon dioxide, as one of the greenhouse gases, has been strictly restricted in recent years. [0003] The effective thermal efficiency of a diesel engine directly affects the level of carbon dioxide emissions. High thermal efficiency diesel engines can not only meet the requirements of carbon dioxide emission regulations, but also achieve good power performance and improve economy. The experimental research on the optimization of effective thermal efficiency often requires high-precisi...

AI Technical Summary

Problems solved by technology

The calculation method of finite-time thermodynamic derivation is complicated, and the results are too theoretical, and the practical reference is weak

However, the existing zero-dimensional models mainly use semi-empirical formulas such as Weber formula or double Weber formula to simulate the combustion process. This type of model is weak in combustion adjustability, and it is difficult to predict the general effective thermal efficiency for different diesel engine models.

In addition, most of the existing zero-dimensional models only consider the combustion of diesel as fuel, which is difficult to adapt to the existing development trend of diesel alternative fuels

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