Engine Knock Rating of Natural Gases—Methane Number

1993 ◽  
Vol 115 (4) ◽  
pp. 769-776 ◽  
Author(s):  
T. W. Ryan ◽  
T. J. Callahan ◽  
S. R. King
Keyword(s):  
Equivalence Ratio ◽  
Gas Composition ◽  
Limited Data ◽  
Engine Operation ◽  
Natural Gases ◽  
Gaseous Fuels ◽  
Engine Knock ◽  
Methane Number ◽  
And Control ◽  
Propane Butane

A procedure has been developed and documented for determining the methane number of gaseous fuels. The methane number provides an indication of the knock tendency of the fuel. An experimental test matrix was designed for quantifying the effects of ethane, propane, butane, and CO2. A unique gas mixing and control system was developed to supply test gases to the engine and to control the equivalence ratio and engine operation. The results of the experiments agreed well with the limited data published in the literature. Predictive equations were developed for the methane number (MN) of gaseous fuels using the gas composition. The forms of these equations are suitable for incorporation in a computer program or a spreadsheet.

Behavior Prediction Model in Gas Fueled Spark Ignition Internal Combustion Engines Turbocharged for Genset Application

2013 ◽  
Author(s):  
Jorge Duarte Forero ◽  
German Amador Diaz ◽  
Fabio Blanco Castillo ◽  
Lesme Corredor Martinez ◽  
Ricardo Vasquez Padilla
Keyword(s):  
Equivalence Ratio ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Inlet Temperature ◽  
Combustion Engines ◽  
Gaseous Fuels ◽  
Methane Number

In this paper, a mathematical model is performed in order to analyze the effect of the methane number (MN) on knock tendency when spark ignition internal combustion engine operate with gaseous fuels produced from different thermochemical processes. The model was validated with experimental data reported in literature and the results were satisfactory. A general correlation for estimating the autoignition time of gaseous fuels in function of cylinder temperature, and pressure, equivalence ratio and methane number of the fuel was carried out. Livengood and Wu correlation is used to predict autoignition in function of the crank angle. This criterium is a way to predict the autoignition tendency of a fuel/air mixture under engine conditions and consider the ignition delay. A chemical equilibrium model which considers 98 chemical species was used in this research in order to simulate the combustion of the gaseous fuels at differents engine operating conditions. The effect of spark advance, equivalence ratio, methane number (MN), charge (inlet pressure) and inlet temperature (manifold temperature) on engine knocking is evaluated. This work, explore the feasibility of using syngas with low methane number as fuel for commercial internal combustion engines.

Knock Rating of Gaseous Fuels

2003 ◽  
Vol 125 (2) ◽  
pp. 500-504 ◽  
Author(s):  
A. A. Attar ◽  
G. A. Karim
Keyword(s):  
Binary Mixtures ◽  
Compression Ratio ◽  
Equivalence Ratio ◽  
Spark Ignition ◽  
The Other ◽  
Mixture Composition ◽  
Spark Ignition Engines ◽  
Gaseous Fuels ◽  
Spark Timing ◽  
Methane Number

The knock tendency in spark ignition engines of binary mixtures of hydrogen, ethane, propane and n-butane is examined in a CFR engine for a range of mixture composition, compression ratio, spark timing, and equivalence ratio. It is shown that changes in the knock characteristics of binary mixtures of hydrogen with methane are sufficiently different from those of the binary mixtures of the other gaseous fuels with methane that renders the use of the methane number of limited utility. However, binary mixtures of n-butane with methane may offer a better alternative. Small changes in the concentration of butane produce almost linearly significant changes in both the values of the knock limited compression ratio for fixed spark timing and the knock limited spark timing for a fixed compression ratio.

Concepts for the Adaptation of SI Gas Engines to Changing Methane Number

1994 ◽  
Vol 116 (4) ◽  
pp. 733-739 ◽  
Author(s):  
H.-J. Schiffgens ◽  
H. Endres ◽  
H. Wackertapp ◽  
E. Schrey
Keyword(s):  
Control Device ◽  
Otto Cycle ◽  
Commercial Vehicles ◽  
Lean Burn ◽  
Engine Operation ◽  
Joint Project ◽  
Engine Knock ◽  
Clean Air ◽  
Emission Limits ◽  
Methane Number

In a joint project of FEV Motorentechnik and Ruhrgas AG, the design of stoichiometric and lean-burn Otto engines was optimized by selective modifications to the design and operating parameters to accommodate changing methane numbers (LPG addition to CNG). Of particular importance was knock-free engine operation at a low NOx output to meet the requirements of the German Clean Air Code while concurrently achieving both high efficiencies and mean effective pressures. Based upon the results obtained, concepts for the control of Otto-cycle gas engines to accept changing methane numbers were developed. The newly developed gas engine control device allows these concepts to meet the requirement of the German Clean Air Code with economically viable conditions while preventing engine knock. Furthermore, the test results show that dedicated Otto-cycle gas engines can meet the most stringent emission limits for commercial vehicles while maintaining high efficiencies.

Performance Prediction of Gas Turbine Under Different Strategies Using Low Heating Value Fuel

2013 ◽  
Author(s):  
Edson Batista da Silva ◽  
Marcelo Assato ◽  
Rosiane Cristina de Lima
Keyword(s):  
Natural Gas ◽  
Gas Turbine ◽  
Equivalence Ratio ◽  
Safe Operation ◽  
Engine Operation ◽  
Heating Value ◽  
Gasification Process ◽  
Surge Margin ◽  
And Performance ◽  
Industrial Gas Turbine

Usually, the turbogenerators are designed to fire a specific fuel, depending on the project of these engines may be allowed the operation with other kinds of fuel compositions. However, it is necessary a careful evaluation of the operational behavior and performance of them due to conversion, for example, from natural gas to different low heating value fuels. Thus, this work describes strategies used to simulate the performance of a single shaft industrial gas turbine designed to operate with natural gas when firing low heating value fuel, such as biomass fuel from gasification process or blast furnace gas (BFG). Air bled from the compressor and variable compressor geometry have been used as key strategies by this paper. Off-design performance simulations at a variety of ambient temperature conditions are described. It was observed the necessity for recovering the surge margin; both techniques showed good solutions to achieve the same level of safe operation in relation to the original engine. Finally, a flammability limit analysis in terms of the equivalence ratio was done. This analysis has the objective of verifying if the combustor will operate using the low heating value fuel. For the most engine operation cases investigated, the values were inside from minimum and maximum equivalence ratio range.

EFFECT OF AIR HEATING ON CONCENTRATION OF NITROGEN OXIDES IN COMBUSTION PRODUCTS OF GASEOUS FUELS

2020 ◽  
Vol 0 (10) ◽  
pp. 35-40
Author(s):  
S.I. Gertsyk ◽  
◽  
I.V. Belyakov ◽  
Keyword(s):  
Blast Furnace ◽  
High Temperature ◽  
Nitrogen Oxides ◽  
Combustion Products ◽  
Blast Furnaces ◽  
Natural Gases ◽  
Gaseous Fuels ◽  
Air Heating ◽  
Formation Probability ◽  
Oxide Concentration

The formation probability of nitrogen oxides in combustion products of mixed blast-furnace and natural gases under different conditions of combustion was calculated. It has been found out that heating the air incoming into burners of high-temperature blast-furnaces sharply increases concentration of nitrogen oxides in combustion products (by 1.5-1.75 times). It was notices that in furnaces where temperature was less than 950-1000 °С, heating the air up to 400 °С increased NOx content in gases released to the atmosphere no more than by 20-23%, and oxide concentration was in limits of sanitary standards.

scholarly journals Capacitive and Infrared Gas Sensors for the Assessment of the Methane Number of LNG Fuels

Sensors ◽  
2020 ◽  
Vol 20 (12) ◽  
pp. 3345 ◽  
Author(s):  
Jörgen Sweelssen ◽  
Huib Blokland ◽  
Timo Rajamäki ◽  
Arjen Boersma
Keyword(s):  
Power Plants ◽  
Low Cost ◽  
Energy Transition ◽  
Capacitive Sensor ◽  
Fuel Quality ◽  
Engine Operation ◽  
Major Player ◽  
The World ◽  
Liquid Natural Gas ◽  
Methane Number

Liquid Natural Gas (LNG) is an energy source that is becoming more important in energy transition, as the world is facing lower the CO2 emissions and backup sources for wind and solar energy are needed. LNG is becoming a major player not only as fuel for power plants, but also in transport and mobility. However, the composition of LNG varies significantly between the various production locations around the world, and the layering of hydrocarbons with different molecular weights takes place even in LNG containers. This is especially critical for LNG engines, in which the ignition properties of the gas depend heavily on the fuel quality or Methane Number (MN) of the gas. For optimized engine operation and motor management, this fuel quality should be measured regularly, preferably online and by a small and low-cost sensor. This paper presents two sensor solutions for the assessment of the full gas composition. For both sensors, the standard deviation in the composition of the relevant hydrocarbons was low enough to calculate the Methane Number with an accuracy of approximately 1 MN unit. It was demonstrated that the electronic capacitive sensor was better suited to assess the higher hydrocarbons, whereas the infrared sensor showed higher selectivity for the lower hydrocarbons.

scholarly journals Multiparameter Sensor Array for Gas Composition Monitoring

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 867
Author(s):  
Arjen Boersma ◽  
Jörgen Sweelssen ◽  
Huib Blokland
Keyword(s):  
Energy Content ◽  
Low Cost ◽  
Water Vapor Pressure ◽  
Calorific Value ◽  
Energy Transition ◽  
Gas Composition ◽  
Wobbe Index ◽  
Liquid Natural Gas ◽  
Methane Number ◽  
Composition Monitoring

In the energy transition from fossil to renewable resources, gas is foreseen to play an important role. However, the composition of the gas is expected to change due to a wider variation of sources. In order to mitigate potential challenges for distributors and end-users, a new low-cost gas composition sensor was developed that will be able to monitor the composition and energy content of these gas sources, ranging from biogas to liquid natural gas (LNG). Together with industrial and academic partners a gas sensor was realized that can be inserted in an existing gas grid. A first demonstrator was realized that was small enough to be used in low and medium pressure gas pipes (100 mbarg—8 barg). Adding the pressure and temperature data to the chip readings enables to determine the concentrations of methane, ethane, propane, butane, nitrogen and carbon dioxide, including small fluctuations in water vapor pressure and subsequently calculate the Calorific Value, Wobbe Index and Methane Number.

scholarly journals The Balance of Multi-phase Gathering and Transport Systems

2019 ◽  
Vol 290 ◽  
pp. 10002
Author(s):  
Cristian Nicolae Eparu ◽  
Sorin Neacsu ◽  
Renata Radulescu ◽  
Alina Petronela Prundurel
Keyword(s):  
Liquid State ◽  
Transport Systems ◽  
Gas Composition ◽  
Transport Parameters ◽  
Gaseous State ◽  
Natural Gases ◽  
Multi Phase

Natural gases are a mixture of hydrocarbons which are generally in a gaseous state. Due to the variation in transport parameters (pressure, temperature) and gas composition, there may be sectors where those appear in liquid state, the condensate. The paper presents a system for managing the quantities of fluids from a network in which the liquid state appears. Based on a simulator that includes flash computation, a physical balance of the transport or gathering network can be made.

CONTROL PERFORMANCE OF ER ENGINE MOUNT SUBJECTED TO TEMPERATURE VARIATIONS

2005 ◽  
Vol 19 (07n09) ◽  
pp. 1675-1681 ◽  
Author(s):  
H. J. SONG ◽  
S. B. CHOI ◽  
K. S. KIM
Keyword(s):  
Temperature Variation ◽  
Flow Mode ◽  
Control Performance ◽  
Damping Force ◽  
Engine Operation ◽  
Noise And Vibration ◽  
Vehicle Systems ◽  
Time Domains ◽  
Engine Mount ◽  
And Control

A key function of engine mount of vehicle systems is to support engine mass and isolate noise and vibration from engine disturbance forces. One of attractive candidates to achieve this goal is to utilize a semi-active ER engine mount. By applying this, we can effectively control damping force and hence the noise and vibration by just controlling the intensity of electric field. However, control performance of the engine mount may be very sensitive to temperature variation during engine operation. In this work, we investigate dynamic and control performances of ER engine mount with respect to the temperature variation. In order to undertake this, a flow-mode type of ER engine mount is designed and manufactured. Displacement transmissibility is experimentally evaluated for 1 degree of freedom. The ER engine mount is then incorporated with full-vehicle model in order to investigate vibration control performance. After formulating the governing equation of motion, a semi-active controller is designed. The controller is implemented through a hardware-in-the-loop simulation (HILS), and control responses such as acceleration level at various engine speeds are evaluated in the frequency and time domains.

scholarly journals Equivalence Ratio-EGR Control of HCCI Engine Operation and the Potential for Transition to Spark-Ignited Operation

2001 ◽  
Author(s):  
Joel Martinez-Frias ◽  
Salvador M. Aceves ◽  
Daniel Flowers ◽  
J. Ray Smith ◽  
Robert Dibble
Keyword(s):  
Equivalence Ratio ◽  
Engine Operation ◽  
Hcci Engine
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