Operating Characteristics of a Spark-Ignition Engine Using the Second Law of Thermodynamics: Effects of Speed and Load

2000 ◽  
Author(s):  
Jerald A. Caton
Keyword(s):  
Second Law Of Thermodynamics ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Second Law ◽  
Operating Characteristics

scholarly journals EXERGY DESTRUCTION AND CHEMICAL IRREVERSIBILITIES DURING COMBUSTION IN SPARK – IGNITION ENGINE USING OXYGENATED AND HYDROCARBON FUELS

2013 ◽  
pp. 7-11
Author(s):  
MUNAWAR NAWAB KARIMI ◽  
SANDEEP KUMAR KAMBOJ
Keyword(s):  
Combustion Engine ◽  
Second Law Of Thermodynamics ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Second Law ◽  
Exergy Destruction ◽  
Efficient Utilization ◽  
Dead State ◽  
Energy Economy ◽  
Volume Entropy

The growing concern for energy, economy and environment calls for efficient utilization of natural resources in developing useful work. Second law of thermodynamics provides different perspective compared with first law. This paper provides an overview of the quantitative levels of exergy destruction and chemical irreversibilities during the combustion. For the adiabatic combustion at constant volume, entropy generation approach with second law of thermodynamics is applied. The result of this study is based on a spark ignition, single cylinder combustion engine with stoichiometric condition. Iso-octane, methane, methanol and ethanol are the fuels examined. This study shows that exergy destruction during combustion decreases with the increase in reactant temperature and compression ratios, for all the fuels. Exergy destruction during combustion using entropy balance approach for compression ratio range of 7 to 11 found to vary between 16.18 to 21.52%. Chemical irreversibilities calculated at the restricted dead state are found to be in the range of 2.99 to 3.6% for different fuels

Utilizing a Cycle Simulation to Examine the Use of EGR for a Spark-Ignition Engine Including the Second Law of Thermodynamics

2006 ◽  
Author(s):  
Jerald A. Caton
Keyword(s):  
Combustion Process ◽  
Second Law Of Thermodynamics ◽  
Thermodynamic Cycle ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Second Law ◽  
Base Case ◽  
Nitric Oxides ◽  
Automotive Engine ◽  
Cycle Simulation

The use of exhaust gas recirculation (EGR) for a spark-ignition engine was examined using a thermodynamic cycle simulation including the second law of thermodynamics. Both a cooled and an adiabatic EGR configuration were considered. The engine was a 5.7 liter, automotive engine operating from idle to wide open throttle, and up to 6000 rpm. First, the reduction of nitric oxides is quantified for the base case condition (bmep = 325 kPa, 1400 rpm, φ = 1.0 and MBT timing). Over 90% reduction of nitric oxides is obtained with about 18% EGR for the cooled configuration, and with about 26% EGR for the adiabatic configuration. For constant load and speed, the thermal efficiencies increase with increasing EGR for both configurations, and the results show that this increase is mainly due to decreasing pumping losses and decreasing heat losses. In addition, results from the second law of thermodynamics indicated an increase in the destruction of availability (exergy) during the combustion process as EGR levels increase for both configurations. The major reason for this increase in the destruction of availability was the decrease in the combustion temperatures. Complete results for the availability destruction are provided for both configurations.

First and Second Law Analyses of a Spark-Ignition Engine Using Either Isooctane or Hydrogen: An Initial Assessment

2006 ◽  
Author(s):  
Jerald A. Caton
Keyword(s):  
Nitric Oxide ◽  
Thermal Efficiency ◽  
Equivalence Ratio ◽  
Performance Metrics ◽  
Combustion Process ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Second Law ◽  
Cycle Simulation ◽  
Nitric Oxide Emissions

The use of either hydrogen or isooctane for a spark-ignition engine was examined using a thermodynamic cycle simulation including the second law of thermodynamics. The engine studied was a 5.7 liter, automotive engine operating from idle to wide open throttle. The hydrogen or isooctane was assumed premixed with the air. Two features of hydrogen combustion that were included in the study were the higher flame speeds (shorter burn durations) and the wider lean flammability limits (lean equivalence ratios). Three cases were considered for the use of hydrogen: (1) standard burn duration and an equivalence ratio of 1.0, (2) a shorter burn duration and an equivalence ratio of 1.0, and (3) a shorter burn duration and variable, lean equivalence ratios. The results included thermal efficiencies, other performance metrics, second law parameters, and nitric oxide emissions. In general, for the cases with an equivalence of 1.0, the brake thermal efficiency was slightly lower for the hydrogen cases due to the higher temperatures and higher heat losses. For the variable, lean equivalence ratio cases, the thermal efficiency was higher for the hydrogen case relative to the isooctane case. Due to the higher temperatures, the hydrogen cases had over 50% higher nitric oxide emissions compared to the isooctane case at the base conditions. In addition, the second law analyses indicated that the destruction of availability during the combustion process was lower for the base hydrogen case (11.2%) relative to the isooctane case (21.1%).

Effect of Methanol Additive with LPG in Three Cylinder Four Stroke S.I. Engine

2014 ◽  
Vol 592-594 ◽  
pp. 1503-1509 ◽  
Author(s):  
S. Somasundaram ◽  
T. Mohanraj ◽  
S. Pasupathy Raju
Keyword(s):  
Natural Gas ◽  
Petroleum Refining ◽  
Research Work ◽  
Spark Ignition ◽  
Solenoid Valve ◽  
Spark Ignition Engine ◽  
Experimental Results ◽  
Operating Characteristics ◽  
Transportation Fuel ◽  
Overall Performance

LPG is a mixture of gas, mainly propane and butane. It is commonly used as a fuel for cooking and as a transportation fuel. It is normally created as a by-product of petroleum refining and from the production of Natural Gas. An experiment is conducted to obtain the operating characteristics of the four stroke three cylinder inline water cooled spark ignition engine operated with LPG and methanol. The engine is started with LPG and methanol with various ratios at constant volume rate in the vaporizer. Solenoid valve was used to allow either LPG or petrol in the carburetor. The LPG supplied through the vaporizer and the quantity is metered by hanging type weighing scale. The additives are added with LPG before supplied to the vaporizer. The performance characteristics of engine were analyzed using petrol with increase in load. Further the engine run with LPG and adjusts the flow based on the mixing of additives. The best ratio of additives can be selected based on the experimental results obtained in the engine.The findings of the present research work suggest that optimum % of methanol as additive to increase the overall performance and to reduce the emission levels.

Second law analysis of a spark ignition engine under high values of ignition retard

2012 ◽  
Vol 58 (1) ◽  
pp. 79 ◽  
Author(s):  
Hakan Ozcan ◽  
Mustafa Özbey ◽  
M. Sait Söylemez ◽  
Bahattin Topaloglu
Keyword(s):  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Second Law ◽  
Second Law Analysis
Sign in / Sign up

Export Citation Format

Share Document