Reducing the exhaust emissions of an spark ignition engine by means of engine modifications requires consideration of the effects of these modifications on the variations of crankshaft torque and the engine roughness respectively. Only if the roughness does not exceed a certain level the vehicle do not begin to surge. This paper presents a method for controlling the air-fuel ratio for a lean bu...

Diesel engine emission standards are being more stringent as it gains more publicity in industry and transportation. Hence, designers have to suggest new controlling strategies which result in small amounts of emissions and a reasonable fuel economy. To achieve such a target, multi-objective optimization methodology is a good approach inasmuch as several types of ...

Piston scuffing is one of the destructive faults in internal combustion (IC) engines. There are different causes to make this fault that lack of lubricant is the most important one among them. The purpose of this paper is the quantitative study of the piston scuffing effects on the engine performance parameters which is a new research direction in the IC engine filed. For this reason, several e...

Performance evaluation of Internal Combustion Engines (ICEs) and setting different emission standards has manifested the importance of pollution reduction as well as the optimal fuel consumption of these engines. Accordingly, the Engine Management Systems (EMS) are utilized which resulted in optimizing the power alongside the decrease in pollutant emission, through preparing the appropriate air...

This research uses computational modeling to explore another method to increase diesel engine performance while maintaining low pollutant emission levels. Previous studies have shown that injection-rate profiles and injector configurations play important roles on the performance and emissions of particulate and NOx in DI diesel engines. Since the most important engine design parameters, includi...

excessive cutting depth during leveling of agricultural land increases power needed by the tractor drawbar and will result in undesirable slippage and excessive strain on the tractor engine.  the result of sustained excess will be the break-down of the tractor. an auxiliary blade depth controller to prevent overloading during leveling was designed, fabricated and evaluated in this study. the sy...

Establishing heuristic-search based chess programs as appropriate tools for estimating human skill levels at chess may seem impossible due to the following issues: the programs’ evaluations and decisions tend to change with the depth of search and with the program used. In this research, we provide an analysis of the differences between heuristic-search based programs in estimating chess skill....

A computational optimization was performed for a direct-injection diesel engine using three-dimensional modeling. Fully transient CFD analyses of different valve profile strategies for the intake and compression strokes were performed to evaluate the effects on both engine performance and in-cylinder flow-field evolution. The turbulence model was used along with the second order linear upwin...

<pre><em>The fundamental problem in meeting fuel consumption for the operation of diesel engines is terms costs and ensuring availability fuel. So that idea using alternative fuels other than arises. And recommendation gas (compressed natural gas) several reasons including cheaper prices Indonesia has abundant reserves. Because properties CNG oil are different, it necessary to modif...