Study of the working process of a gas-diesel engine using ammonia as a main fuel.

Key words: ammonia, nitrogen, carbon-free fuel, gas-diesel, CFD-simulation

Abstract

In this paper, we consider the possibility of efficient operation of an internal combustion engine in a gas-diesel cycle using ammonia as the main fuel. An engine simulation using ANSYS Forte examines the effect of fuel injection characteristics and in-cylinder combustion parameters in a dual-fuel compression ignition engine using ammonia.

The gas-diesel engine YaMZ-5345 is considered as an object of study. The results obtained are compared with the simulation of the diesel cycle performed in the RP-TOX program.

The study showed that, with appropriate optimization of the work process, it is possible

to achieve almost complete replacement of diesel fuel with ammonia while maintaining the same power and efficiency, using diesel fuel only as an ignition dose - no more than 10%.

Evaluation of environmental indicators shows a significant reduction in CO2 concentration in the exhaust gases, which is the main advantage of using carbon-free fuels. The presence of unburned ammonia and nitrogen oxides in the exhaust gases is noted.

 

The effect of the intake system configuration on the power of a 7.5/6.0 diesel engine.

Key words:  diesel engine, intake system, pipeline transverse profiling, bench tests, consumption characteristics, engine power

Abstract

At the same time, the improvement of gas exchange processes is an effective way to improve the specific performance of diesel engines. The article presents an analysis of the effect of cross-profiling of the intake pipeline of a diesel engine on its consumption characteristics and power based on experimental studies. The article describes experimental stands and measuring instruments. Modification of the intake system consisted in the use of an intake pipe with square and triangular sections. The article presents data on the flow characteristics through the intake systems of a piston engine model and the power characteristics of a diesel engine with different modifications of the intake pipe. It was found that the use of profiled pipes caused an increase in air flow through the engine intake system in the range of 5_17% compared to the basic configuration. It was revealed that there was an increase in diesel power by 3_15% when using profiled pipes in the intake system compared to the basic modification. The data obtained are useful for the modernization of the intake systems of existing engines and the development of new diesels with promising technical and economic indicators.

 

Multifunctional additives for diesel fuel: mechanism of action, efficiency, problems.

Key words: multifunctional additive, diesel fuel, combustion process, effective power, fuel consumption,

exhaust gas temperature, smokiness, exhaust gas toxicity, ignition delay

Abstract

Multifunctional additives (MFAs) improve the combustion process of fuel, increase its washing abilities, reduce the level of contamination of the working cavities of the combustion chamber, etc. But no in-depth research has been conducted on the effect of their concentration on engine operation, manufacturers of MFAs give general recommendations, without taking into account the real composition of the base fuel and engine operating modes.

The article presents the results of special motor-bench studies on the effect of MFA concentration on engine operation: fuel consumption, exhaust gas smoke. The studies were carried out when the engine was operating according to the load characteristic for the summer

DT-L-K5 and winter DT-Z-K5 on diesel fuels of the same brand. The results of engine indexing (measurement of instantaneous pressure in the cylinder) with a calculated study of diagrams to determine the dynamics of active heat generation in the cylinder when the engine is running on base fuel and containing MFPs in different concentrations are also presented.

As a result, a decrease in the ignition delay of the fuel, an increase in the rate of combustion in the kinetic phase and a reduction in the total duration of combustion were determined. The value of the optimal concentration of MFAs, which significantly depends on the hydrocarbon composition of the base fuel, is revealed.

Modular approaches and algorithms for the creation of steam turbines.

Key words: steam turbine, turbine plant, steam turbine manufacturing, power engineering, competitiveness, module, modular approach, unification, algorithm, life cycle, labor intensity

Abstract

The most important issues in the development of steam turbine engineering include the improvement of tools for the development, production, operation and life cycle management of the main and auxiliary equipment.

Quite often, measures to improve the preparation of production and actual manufacturing are carried out inconsistently, without subordination to a common goal, with differences in approaches, tools and means of solution. This leads to duplication of work, lack of a common line, and sometimes incompatibility.

Irrational and uneven problem solving should change in favor of a systematic approach to the development of the enterprise, its products and tools for managing the housing and communal services of manufactured products.

The designs and approaches to the development of steam turbines and turbine plants

of foreign and Russian turbine manufacturers are described. It is indicated that the modular principle of LEGO and a single library of standard elements makes it possible to achieve greater efficiency of the life cycle of steam turbine equipment and its higher weighted averages than using the base platform, which is explained by the need for such a principle to create an optimized shell with limited options for optional replacement of parts and systems and fundamentally similar to individual design approaches.

An algorithm for a modular approach to creating a steam turbine and improving its design in life cycle management is proposed.