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.

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.

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 Rapid Liquid Fuel Mixing for Lean-Burning Combustors: Low-Power Performance

2001 ◽  
Vol 123 (3) ◽  
pp. 574-579 ◽  
Author(s):  
M. Y. Leong ◽  
C. S. Smugeresky ◽  
V. G. McDonell ◽  
G. S. Samuelsen
Keyword(s):  
Low Power ◽  
Gas Turbine ◽  
Liquid Fuel ◽  
Direct Injection ◽  
Fuel Injector ◽  
Power Performance ◽  
Lean Burn ◽  
Engine Operation ◽  
Turbine Engine ◽  
Lean Direct Injection

Designers of advanced gas turbine combustors are considering lean direct injection strategies to achieve low NOx emission levels. In the present study, the performance of a multipoint radial airblast fuel injector Lean Burn injector (LBI) is explored for various conditions that target low-power gas turbine engine operation. Reacting tests were conducted in a model can combustor at 4 and 6.6 atm, and at a dome air preheat temperature of 533 K, using Jet-A as the liquid fuel. Emissions measurements were made at equivalence ratios between 0.37 and 0.65. The pressure drop across the airblast injector holes was maintained at 3 and 7–8 percent. The results indicate that the LBI performance for the conditions considered is not sufficiently predicted by existing emissions correlations. In addition, NOx performance is impacted by atomizing air flows, suggesting that droplet size is critical even at the expense of penetration to the wall opposite the injector. The results provide a baseline from which to optimize the performance of the LBI for low-power operation.

scholarly journals Rapid Liquid Fuel Mixing for Lean-Burning Combustors: Low-Power Performance

2000 ◽  
Author(s):  
May Y. Leong ◽  
Craig S. Smugeresky ◽  
Vincent G. McDonell ◽  
G. Scott Samuelsen
Keyword(s):  
Low Power ◽  
Gas Turbine ◽  
Liquid Fuel ◽  
Direct Injection ◽  
Fuel Injector ◽  
Power Performance ◽  
Lean Burn ◽  
Engine Operation ◽  
Turbine Engine ◽  
Lean Direct Injection

Designers of advanced gas turbine combustors are considering lean direct injection strategies to achieve low NOx emission levels. In the present study, the performance of a multipoint radial airblast fuel injector (“Lean Burn Injector—LBI”) is explored for various conditions that target low-power gas turbine engine operation. Reacting tests were conducted in a model can combustor at 4 atm and 6.6 atm, and at a dome air preheat temperature of 533 K, using Jet-A as the liquid fuel. Emissions measurements were made at equivalence ratios between 0.37 and 0.65. The pressure drop across the airblast injector holes was maintained at 3% and 7–8%. The results indicate that the LBI performance for the conditions considered is not sufficiently predicted by existing emissions correlations. In addition, NOx performance is impacted by atomizing air flows, suggesting that droplet size is critical even at the expense of penetration to the wall opposite the injector. The results provide a baseline from which to optimize the performance of the LBI for low-power operation.

Evaluation of a Lean-Burn Natural Gas Engine Operating on Variable Methane Number Fuel

2011 ◽  
Author(s):  
Cory J. Kreutzer ◽  
Daniel B. Olsen ◽  
Robin J. Bremmer
Keyword(s):  
Natural Gas ◽  
High Efficiency ◽  
Engine Performance ◽  
Combustion Stability ◽  
Lean Burn ◽  
Natural Gas Engines ◽  
Spark Timing ◽  
Gas Compression ◽  
Fuel Blending ◽  
Methane Number

Wellhead gas from which pipeline natural gas originates has significant variability in composition due to natural variations in deposits. Gas quality is influenced by relative concentrations of both inert and hydrocarbon species. Gas compression engines utilizing wellhead gas as a fuel source often require significant installation time and adjustment of stock configuration due to fuel compositions that vary with time and location. Lean burn natural gas engines are chosen as wellhead compression engines for high efficiency and low emissions while minimizing the effect of variable gas composition. Ideal engine conditions are maintained by operating within the knock and misfire limits of the engine. Additional data is needed to find engine operational limitations. In this work, experimental data was collected on a Cummins GTA8.3SLB engine operating on variable methane number fuel under closed-loop equivalence ratio control. A fuel blending system was used to vary methane number to simulate wellhead compositions. NOx and CO emissions were found to increase with decreasing methane number while combustion stability remained constant. In addition, the effects of carbon dioxide and nitrogen diluents in the fuel were investigated. When diluents were present in the fuel, engine performance could be maintained by spark timing advance.

scholarly journals Numerical Simulation of a Wall-Flow Particulate Filter Made of Biomorphic Silicon Carbide Able to Fit Different Fuel/Biofuel Inputs

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 945
Author(s):  
M. Pilar Orihuela ◽  
Onoufrios Haralampous ◽  
Ricardo Chacartegui ◽  
Miguel Torres García ◽  
Julián Martínez-Fernández
Keyword(s):  
Silicon Carbide ◽  
Alternative Fuels ◽  
Internal Combustion Engines ◽  
Particle Distribution ◽  
Particulate Filter ◽  
Loading Test ◽  
Engine Operation ◽  
Combustion Gases ◽  
Wall Flow ◽  
Emission Limits

To meet the increasingly strict emission limits imposed by regulations, internal combustion engines for transport applications require the urgent development of novel emission abatement systems. The introduction of biodiesel or other biofuels in the engine operation is considered to reduce greenhouse gas emissions. However, these alternative fuels can affect the performance of the post-combustion systems due to the variability they introduce in the exhaust particle distribution and their particular physical properties. Bioceramic materials made from vegetal waste are characterized by having an orthotropic hierarchical microstructure, which can be tailored in some way to optimize the filtration mechanisms as a function of the particle distribution of the combustion gases. Consequently, they can be good candidates to cope with the variability that new biofuel blends introduce in the engine operation. The objective of this work is to predict the filtration performance of a wall-flow particulate filter (DPF) made of biomorphic silicon carbide (bioSiC) with a systematic procedure that allows to eventually fit different fuel inputs. For this purpose; a well-validated DPF model available as commercial software has been chosen and adapted to the specific microstructural features of bioSiC. Fitting the specific filtration and permeability parameters of this biomaterial into the model; the filtration efficiency and pressure drop of the filter are predicted with sufficient accuracy during the loading test. The results obtained through this study show the potential of this novel DPF substrate; the material/microstructural design of which can be adapted through the selection of an optimum precursor.

Struggling for Air

2016 ◽  
Author(s):  
Richard Revesz ◽  
Jack Lienke
Keyword(s):  
Air Pollution ◽  
Electricity Market ◽  
Environmental Protection Agency ◽  
Power Plants ◽  
Environmental Law ◽  
Power Sector ◽  
Industrial Facilities ◽  
Major Energy Source ◽  
Clean Air ◽  
Emission Limits

Since the beginning of the Obama Administration, conservative politicians have railed against the President's "War on Coal." As evidence of this supposed siege, they point to a series of rules issued by the Environmental Protection Agency that aim to slash air pollution from the nation's power sector . Because coal produces far more pollution than any other major energy source, these rules are expected to further reduce its already shrinking share of the electricity market in favor of cleaner options like natural gas and solar power. But the EPA's policies are hardly the "unprecedented regulatory assault " that opponents make them out to be. Instead, they are merely the latest chapter in a multi-decade struggle to overcome a tragic flaw in our nation's most important environmental law. In 1970, Congress passed the Clean Air Act, which had the remarkably ambitious goal of eliminating essentially all air pollution that posed a threat to public health or welfare. But there was a problem: for some of the most common pollutants, Congress empowered the EPA to set emission limits only for newly constructed industrial facilities, most notably power plants. Existing plants, by contrast, would be largely exempt from direct federal regulation-a regulatory practice known as "grandfathering." What lawmakers didn't anticipate was that imposing costly requirements on new plants while giving existing ones a pass would simply encourage those old plants to stay in business much longer than originally planned. Since 1970, the core problems of U.S. environmental policy have flowed inexorably from the smokestacks of these coal-fired clunkers, which continue to pollute at far higher rates than their younger peers. In Struggling for Air, Richard L. Revesz and Jack Lienke chronicle the political compromises that gave rise to grandfathering, its deadly consequences, and the repeated attempts-by presidential administrations of both parties-to make things right.

Specification, Development, and Testing of the FT8-2 Dry Low NOx Control System

1996 ◽  
Vol 118 (3) ◽  
pp. 547-552
Author(s):  
R. C. Bell ◽  
T. W. Prete ◽  
J. T. Stewart
Keyword(s):  
Control System ◽  
Gas Flow ◽  
Closed Loop ◽  
Engine Test ◽  
Lean Burn ◽  
Engine Operation ◽  
Fuel Gas ◽  
Loop Control ◽  
Engine Model ◽  
Nox Control

This paper describes the specification, development, and testing of the FT8-2 Dry Low NOx control system, and how the lean burn process requires an integration of the control system and combustion hardware. The FT8-2 digital fuel control system was developed to achieve the precise multizone fuel metering of both gas and liquid fuels, the calculation of combustor air flow necessary to achieve Dry Low NOx and the traditional governing/limiting control loops necessary for safe, stable engine operation. The system design goals were accomplished by the concurrent development of software-based fuel metering algorithms and fuel metering hardware. The fuel metering hardware utilizes an all-electronic valve positioner, employing a combination of feedback and software to achieve closed-loop control of actual fuel flow. Extensive testing under actual gas flow conditions and closed-loop bench testing using a real time engine model and fuel system model was conducted to prove system operation and develop system transient response prior to installation on the test engine. The setup and results of the flow testing and closed-loop testing are described. The paper describes the control scheme used to apportion the gas fuel between combustion zones and how external conditions such as ambient temperature and fuel gas composition affect the apportionment. The paper concludes with a description of the control system installation in the engine test cell and a review of engine test results.

Comparison of Emissions and Efficiency of a Turbocharged Lean-Burn Natural Gas and Hythane-Fueled Engine

1997 ◽  
Vol 119 (1) ◽  
pp. 218-226 ◽  
Author(s):  
J. F. Larsen ◽  
J. S. Wallace
Keyword(s):  
Natural Gas ◽  
Specific Energy Consumption ◽  
Oxides Of Nitrogen ◽  
Heavy Duty ◽  
Lean Burn ◽  
Clear Trend ◽  
Engine Operation ◽  
Spark Timing ◽  
Test Engine ◽  
Carbon Dioxide Co2

An experiment was conducted to evaluate the potential for reduced exhaust emissions and improved efficiency, by way of lean-burn engine fuelling with hydrogen supplemented natural gas (Hythane). The emissions and efficiency of the Hythane fuel (15 percent hydrogen, 85 percent natural gas by volume), were compared to the emissions and efficiency of pure natural gas using a turbocharged, spark ignition, 3.1 L, V-6 engine. The feasibility of heavy duty engine fueling with Hythane was assessed through testing conducted at engine speed and load combinations typical of heavy-duty engine operation. Comparison of the efficiency and emissions at MBT spark timing revealed that Hythane fueling of the test engine resulted in consistently lower brake specific energy consumption and emissions of total hydrocarbons (THC), carbon monoxide (CO), and carbon dioxide (CO2), at a given equivalence ratio. There was no clear trend with respect to MBT oxides of nitrogen (NOx) emissions. It was also discovered that an improved NOx-THC tradeoff resulted when Hythane was used to fuel the test engine. Consequently, Hythane engine operating parameters can be adjusted to achieve a concurrent reduction in NOx and THC emissions relative to natural gas fueling.

Sign in / Sign up

Export Citation Format

Share Document