scholarly journals Ideal cycle of combustion engine with natural gas as a fuel

2016 ◽  
Vol 62 (Special Issue) ◽  
pp. S14-S20 ◽  
Author(s):  
I. Vitázek ◽  
J. Klúčik ◽  
J. Jablonický ◽  
P. Vereš

The aim of the paper is to present a detailed methodology of calculations of parameters of an ideal working cycle of spark-ignition combustion engine. Natural gas in the form of compressed natural gas (CNG) was used as a fuel. A theoretical ideal cycle is currently described in simplified way. The paper introduces calculations considering excess air, residual space in the cylinder of the engine and the course of properties of gases in dependence on temperature. The thermodynamics of ideal gas mixture was used. A computer program for clear, quick and accurate calculations of this relatively complicated system of relations was designed. The presented methodology of calculations broadens the scope of the theory of combustion engines and enables a precise determination of parameters of combustion engine with natural gas as a fuel.

2019 ◽  
Vol 21 (8) ◽  
pp. 1493-1519
Author(s):  
Abhishek Y Deshmukh ◽  
Carsten Giefer ◽  
Dominik Goeb ◽  
Maziar Khosravi ◽  
David van Bebber ◽  
...  

Direct injection of compressed natural gas in internal combustion engines is a promising technology to achieve high indicated thermal efficiency and, at the same time, reduce harmful exhaust gas emissions using relatively low-cost fuel. However, the design and analysis of direct injection–compressed natural gas systems are challenging due to small injector geometries and high-speed gas flows including shocks and discontinuities. The injector design typically involves either a multi-hole configuration with inwardly opening needle or an outwardly opening poppet-type valve with small geometries, which make accessing the near-nozzle-flow field difficult in experiments. Therefore, predictive simulations can be helpful in the design and development processes. Simulations of the gas injection process are, however, computationally very expensive, as gas passages of the order of micrometers combined with a high Mach number compressible gas flow result in very small simulation time steps of the order of nanoseconds, increasing the overall computational wall time. With substantial differences between in-nozzle and in-cylinder length and velocity scales, simultaneous simulation of both regions becomes computationally expensive. Therefore, in this work, a quasi-one-dimensional nozzle-flow model for an outwardly opening poppet-type injector is developed. The model is validated by comparison with high-fidelity large-eddy simulation results for different nozzle pressure ratios. The quasi-one-dimensional nozzle-flow model is dynamically coupled to a three-dimensional flow solver through source terms in the governing equations, named as dynamically coupled source model. The dynamically coupled source model is then applied to a temporal gas jet evolution case and a cold flow engine case. The results show that the dynamically coupled source model can reasonably predict the gas jet behavior in both cases. All simulations using the new model led to reductions of computational wall time by a factor of 5 or higher.


2021 ◽  
Vol 245 ◽  
pp. 01045
Author(s):  
Guofang Zhang ◽  
Taoping Chen ◽  
Fuping Wang ◽  
Boyu Sun ◽  
Yong Wang ◽  
...  

The deviation factor of natural gas is a coefficient to quantitatively describe the deviation degree between real gas (natural gas) and ideal gas. Generally, the deviation factor of natural gas is measured in PVT cell without considering porous media. However, when natural gas is in underground porous media reservoir, due to the adsorption of porous media, the deviation factor of natural gas in porous media deviates from that measured in conventional PVT cell. Moreover, compared with other gases, CO2 has stronger adsorption capacity. Therefore, in porous media, the deviation factor of natural gas considering the adsorption of porous media is quite different from that measured in conventional PVT cell. In this paper, simulating the isothermal mining conditions in gas reservoir,the deviation factor of natural gas with different CO2 content considering the influence of porous media under different pressure isothermal conditions is studied by using the test of designed sand filled long slim tube in series. And under the same conditions, the deviation factor is compared with that of conventional PVT. The experimental results show that under the same conditions, due to the adsorption of porous media, the deviation factor measured in porous media is smaller than that measured by PVT cell without considering porous media.


2012 ◽  
Vol 148 (1) ◽  
pp. 82-88
Author(s):  
Wojciech GIS ◽  
Edward MENES ◽  
Jerzy WAŚKIEWICZ

The paper discusses issues related to the use of compressed natural gas (CNG) in combustion engines particularly in municipal bus transport. The ecological aspects of the use of natural gas in road transport have been analyzed particularly the exhaust emissions in comparison to the emissions from diesel engines. Advantages and disadvantages of natural gas fueling as well as the current level of CNG use in transport have been presented both in Poland and worldwide. The authors have also indicated the motivating arguments for the use of natural gas.


2020 ◽  
pp. 37-38
Author(s):  
I.K. Aleksandrov ◽  
V.A. Rakov ◽  
N.E. Dyimov

A method for determining of mechanical losses in an internal combustion engine is proposed, the principal difference of which is the rotation of the engine shaft with compressed air. This method provides high reliability results on reduction of fuel consumption and emissions of harmful substances. Keywords ICE, mechanical losses, tests, compressed air [email protected]


2016 ◽  
Vol 822 ◽  
pp. 169-174
Author(s):  
Alexandru Mihai Dima ◽  
Dragos Tutunea ◽  
Marin Bica

The automotive industry represents one of the most important segments of the world economy that has to be in a continue development. The latest procedures for determination of an internal combustion engine performance have a big acquisition cost and demand special conditions even if the tested engine has smaller dimensions. The present paper presents other accessible solutions for this matter.


2019 ◽  
Vol 176 (1) ◽  
pp. 3-9 ◽  
Author(s):  
Michael WEIßNER ◽  
Frank BEGER ◽  
Martin SCHÜTTENHELM ◽  
Gunesh TALLU

Current and further developing CO2- and emission regulations worldwide and the competition to full electric mobility deliver a chal-lenge for internal combustion engines in general. A state of the art solution is the use of natural gas mainly contending methane to reduce CO2 significantly and to offer lowest emission levels. The EU-funded project GasOn developed engine concepts to fully exploit the advantages of CNG. This article describes the development of an innovative, monovalent engine dedicated to Compressed Natural Gas (CNG) and characterised by the lean burn concept and the innovative pre-chamber combustion.


1967 ◽  
Vol 54 (1) ◽  
pp. 129-140 ◽  
Author(s):  
Vladimir Pliška ◽  
Ivan Rychlík

ABSTRACT A procedure for measuring the antidiuretic activity of the neurohypophysial hormones and their synthetic structural analogues in the hydrated rat in the dose range of 5–100 antidiuretic microunits is described. The technique of measurement allows the determination of diuresis over one-minute intervals, as well as the total amount of urine excreted over longer periods. The precision of the measurement is greatly increased by the use of a drop divider. The electrical conductivity of the urine is continuously recorded, and the conductivity and creatinine clearance are correlated with the urine flow. These techniques allow the precise determination of parameters such as the half-life of the antidiuretic effect, formal elimination constants, etc.; they can therefore serve for the comparison even of analogues showing qualitative differences in their antidiuretic effects from the chosen standard (arginine or lysine vasopressin), e. g. analogues of the hormonogen type with prolonged effects.


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