Methods for rapid estimation of indicator and efficient efficiency of internal combustion engines

Author(s):  

The article discusses the issue of a quantitative computational assessment of the efficiency of the thermal cycle of a piston internal combustion engine based on the values of the effective and indicator efficiency. A simplified technique for the operational assessment of the efficiency of the thermal cycle of a piston internal combustion engine is proposed. The technique is based on a mathematical description of thermodynamic processes occurring during the development of the thermal cycle of an engine with ignition of the working mixture from compression (diesel engine), which allows it to be expanded to new engines, including those operating under electronic control. Keywords heat cycle; the working process; diesel; heat content of the working fluid; expansion

Authors Rusinov R.V., Hoodorozhkov S.I., Dobretsov R.Yu., [email protected]. Estimation of the efficiency of the thermal cycle of a piston internal combustion engine The article proposes a simplified technique for the operational assessment of the efficiency of the heat cycle of a piston internal combustion engine. A feature of the developed computational model is the release of the amount of heat consumed for the production of only mechanical energy in the form of a separate component of the heat balance of the cycle. The value of this component is determined by calculation (or according to the results of experiments) in advance, which makes it possible to reduce the number of pre(determined initial data. The methodology is based on a mathematical description of thermodynamic processes occurring during the development of the thermal cycle of an engine with ignition of the working mixture from compression (diesel engine), which allows it to be expanded to new engines of design, including those operating under electronic control. The objects for the application of the calculation method can be diesel engines installed on transport vehicles, both individually and as part of a hybrid power plant, as well as engines of stationary or transportable power plants. The very principle underlying the model can be implemented for engines of other purposes and other thermal cycles. Keywords: heat cycle; the working process; diesel; heat content of the working fluid; expansion


2020 ◽  
Vol 221 ◽  
pp. 01002
Author(s):  
Yury Matveev ◽  
Marina Cherkasova ◽  
Viktor Rassokhin ◽  
Viktor Barskov ◽  
Victor Chernikov ◽  
...  

The article is devoted to the investigation and development of microsteam turbine unit of the LPI design for utilization of heat of exhaust gases of internal combustion engines. This installation will reduce the world carbon dioxide emissions, as well as add useful power for the needs of the consumer. Efficiency and environmental friendliness of the engine will increase. The article discusses development of the main directions of improvement of high-loaded steps of LPI, expansion of modern outlooks on the directions of MRI development and the use of LPI steps in the systems of heat recovery of exhaust gases of the internal combustion engine. The possibility to utilize the heat of exhaust gases of internal combustion engines by means of a turbine unit and the subsequent receipt of additional useful capacities are investigated in many developed countries of the world. Germany, Sweden, Japan, PRC and other leading countries in the automotive industry are intensively conducting works in this direction. The results of such studies have already found application in some freight cars. In the Russian market, this type of turbine is spread very weakly. Turbine unit behind the internal combustion engine works in conditions of low volumetric consumption of the working fluid, which leads to a decrease in the heights of the flow parts of the guides and working grids, because of which the relative gaps in the seals increase. This leads to the growth of leakage of the working fluid. On the other hand, a high degree of pressure reduction when choosing single-stage turbines leads to supersonic


2021 ◽  
Vol 20 (3) ◽  
pp. 97-109
Author(s):  
V. V. Biryuk ◽  
A. A. Gorshkalev ◽  
M. O. Zakharov ◽  
V. L. Larin

On the basis of the available theoretical calculations, methods for calculating the working process and power characteristics of internal combustion engines and the experimental studies carried out, a method for calculating the working process for small-sized two-stroke internal combustion engines was developed and tested. In the course of this work, the following results were obtained: the parameters of the working process and power characteristics of a small two-stroke internal combustion engine; the parameters obtained by calculation during the study of the Evolution 20GX2 engine were compared with the results of an experimental study. According to the results of the comparison, deviations in the values of the parameters of the engine under study from the results of the experimental study at the maximum power and maximum speed modes were identified.


2019 ◽  
Vol 178 (3) ◽  
pp. 182-186
Author(s):  
Zbigniew SROKA ◽  
Maciej DWORACZYŃSKI

The modification of the downsizing trend of internal combustion engines towards rightsizing is a new challenge for constructors. The change in the displacement volume of internal combustion engines accompanying the rightsizing idea may in fact mean a reduction or increase of the defining swept volume change factors and thus may affect the change in the operating characteristics as a result of changes in combustion process parameters - a research problem described in this publication. Incidents of changes in the displacement volume were considered along with the change of the compression space and at the change of the geometric degree of compression. The new form of the mathematical dependence describing the efficiency of the thermodynamic cycle makes it possible to evaluate the opera-tion indicators of the internal combustion engine along with the implementation of the rightsizing idea. The work demonstrated the in-variance of cycle efficiency with different forms of rightsizing.


2021 ◽  
Vol 4 (30) ◽  
pp. 99-105
Author(s):  
A. V. Summanen ◽  
◽  
S. V. Ugolkov ◽  

This article discusses the issues of assessing the technical condition of the camshaft, internal combustion engine. The necessary parameters for assessing the technical condition of the engine camshaft have been determined. How and how to measure and calculate this or that parameter is presented in detail. Methods for calculating the parameters are presented. A scheme and method for measuring neck wear, determining the height of the cam, determining the beating of the central journal of the camshaft are proposed. The main defects of the camshafts are presented. The issues of the influence of these parameters on the operability of the camshaft and the internal combustion engine as a whole are considered.


2021 ◽  
pp. 13-20
Author(s):  

The prospects of using the gas-static suspension of the internal combustion engine piston in transport vehicles and power plants are considered. The diagram of the piston and the method for calculating the stiffness and bearing capacity of the gas layer surrounding the piston are presented, as well as the results of experiments that showed the relevance of this method. The possibility of gas and static centering of the engine piston is confirmed. Keywords: internal combustion engine, piston, gasstatic suspension, stiffness, bearing capacity, gas medium. [email protected]


2019 ◽  
pp. 146808741989358 ◽  
Author(s):  
Mostafa A ElBahloul ◽  
ELsayed S Aziz ◽  
Constantin Chassapis

Fuel conversion efficiency is one of the main concerns in the field of internal combustion engine systems. Although the Otto cycle delivers the maximum efficiency possible in theory, the kinematics of the slider–crank mechanism of the conventional internal combustion engines makes it difficult to reach this level of efficiency in practice. This study proposes using the unique hypocycloid gear mechanism instead of the conventional slider–crank mechanism for the internal combustion engines to increase engine efficiency and minimize frictional power losses. The hypocycloid gear mechanism engine’s kinematics provides the means for the piston-rod assembly to reciprocate in a straight-line motion along the cylinder axis besides achieving a nonlinear rate of piston movement. As a result, this characteristic allows for a true constant-volume combustion, which in turn would lead to higher work output. An in-cylinder gas volume change model of the hypocycloid gear mechanism engine was developed and incorporated into the thermodynamic model for the internal combustion engine cycle. The thermodynamic model of the hypocycloid gear mechanism engine was developed and simulated using MATLAB/Simulink software. A comparison between the conventional engine and the hypocycloid gear mechanism engine in terms of engine performance characteristics showed the enhancements achieved using hypocycloid gear mechanism for internal combustion engine applications. The hypocycloid gear mechanism engine analysis results indicated higher engine efficiency approaching that of the Otto cycle.


1980 ◽  
Vol 194 (1) ◽  
pp. 157-169
Author(s):  
L. C. Hall ◽  
M. E. Saatci

This paper reports on a study into the feasibility of generating steam, using the exhaust gases of a reciprocating internal combustion engine, and expanding it in the cylinders of the engine to produce additional power without increasing the fuel consumption. The study was conducted in three stages; firstly an equivalent ideal thermodynamic cycle was analysed to examine the fundamental principles, secondly a computer simulation was carried out based on a particular engine, and thirdly an attempt was made to modify the engine and run it with steam injection. The results suggest that this proposal is thermodynamically sound and could in practice permit substantial gains in efficiency using relatively straightforward technology.


Mechanik ◽  
2017 ◽  
Vol 90 (7) ◽  
pp. 574-576
Author(s):  
Adam Deptuła ◽  
Piotr Osiński

Presented are possible applications of acoustic diagnostics in inspecting the technical condition of an internal combustion engine with autoignition on the example of the Fiat drive unit with common rail system. As a result of measuring the sound pressure level for specific faults and comparing the noise generated by the motor running smoothly, the detailed maps of changes in the acoustic spectrum are possible to generate. These results may be helpful in the future diagnostics of internal combustion engines. The results of scientific work in the area of research, design and operation of internal combustion engines, conducted at the Department of Automotive Engineering, in cooperation with the Laboratory of Hydraulic Drives & Vibroacoustics of Machines at the Wroclaw University of Technology are included. It has developed an authoritative method of identifying the type of engine damage using game-tree structures. An integrated decision system for induction machine learning was developed to test and identify acoustic properties.


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