Correlation between Emission and Combustion Characteristics with the Compression Ratio and Fuel Injection Timing in Tribologically Optimized Diesel Engine

Abstract

Diesel engines are economical thanks to their combustion process characteristics, which is why they have a high noise emission level as well as exhaust emissions of nitrogen oxide and particulate matters. By continuously changing the value of compression ratio, it is possible to control the power and emissions. Implementation of variable compression ratio has many benefits, such as being able to work with different types of fuel. In this way, it is possible to optimize the combustion process for operation with minimum fuel consumption and emission generation, so that diesel engines can be applied to the framework of future hybrid vehicle concepts, and so forth. As far as the crucial objective of the manuscript is concerned, experimental diesel engine investigation was performed on a roller test-bench by using zero-dimensional computer model (specifically AVL IndiCom Indicate Software). Engine indication was executed with the factory compression ratio value and with three lower values. During our examination, the change in the compression ratio value was achieved by changing the volume of a combustion chamber at a piston-bowl. The results of laboratory research on the experimental engine are presented in the paper when discussing a series of specific parameters (characteristics), such as compression ratio, fuel injection timing, engine speed, as well as load influence on combustion process and exhaust emissions.

Lubrication Modeling of the Reciprocating Piston with High Lateral Load and Various Conditions in a Swash Plate-Type Piston Pump

“…The cylinder chamber pressure was calculated using the pumping dynamics model with no fluid momentum effect in Ref. [3]. In this calculation, constant gap clearances are assumed in three leakage passages, so the cylinder chamber pressure is only given for the calculation of the piston micromotions.…”

“…Pistons are the most important operating elements in reciprocating piston machines, as the performance of such machines is ultimately dependent on the proper behavior of the pistons [1][2][3]. So far, the main areas of interest in this research have involved the optimal selection of the machining clearance [4], design materials [5], piston shape [6][7][8], groove shape [9], etc.…”

“…Moreover, an analysis of the movement of the piston in the lubrication system was also conducted considering various factors. Previous studies include analysis considering secondary motion [26,27], analysis considering bending of the piston rod and crosshead motion [27], multiphase flow analysis using VOF (volume of fluid) considering thermodynamic features [28], and analysis of the piston at high temperature and pressure in diesel engine [3]. In a recent study on a part connected with a reciprocating piston, Li et al investigated the lubrication characteristics of a slipper pair in a large displacement or high-pressure piston pump [29].…”

Analysis of Bearing Assemblies Refit in Agricultural PTO Shafts

“…The mass use of agricultural PTOs in practice, on the one hand, and the lack of repair centers for their maintenance and repair, on the other hand, show the need for significant research in this direction worldwide. In other words, the quality of machines and mechanisms is measured, among other things, by the possibility of their repair and maintenance [9]. The repair of such technical systems is justified only if the original operating conditions can be restored [10].…”

Theoretical and Experimental Study of Conical Tube Hydroforming with One-Sided Axial Feeding

“…The distinction between the two types emerges from whether there is a significant application of material feeding by means of mechanical tools, which is required in cases of complex geometries. THF process utilization assists in designing and optimizing parts for transportation vehicles, such as engine exhaust manifolds, engine cradles, chassis, and many other tubular parts [1][2][3][4][5][6][7].…”