scholarly journals The model for cylinder charge parameters during engine starting

2021 ◽  
Author(s):  
Józef Pszczółkowski Pszczółkowski
Keyword(s):  
Combustion Engine ◽  
Similarity Theory ◽  
Diagnostic Process ◽  
Combustion Engines ◽  
Piston Cylinder ◽  
Factors Influencing ◽  
Start Up ◽  
Flow Through ◽  
Engine Start ◽  
Engine Cycle

The process of cylinder charge – air sucked into the cylinder – transformation during engine start-up phase is characterized. Heat exchange and air flow through piston-cylinder group leakage processes are described as factors influencing the gas thermodynamic parameters. The Woschni formula based on similarity theory was finally used as equation describing heat transfer in combustion engines cylinder. The computational model for cylinder charge parameters in the whole engine cycle during its starting at low temperature is presented. Some taken assumptions and characteristics of partial processes resulting from the computations are shown. There are indicated the possibilities of using the model at internal combustion engine diagnostic process.

scholarly journals Mechanical features of the combustion engine electric starting system

2018 ◽  
Vol 19 (6) ◽  
pp. 661-668
Author(s):  
Józef Pszczółkowski
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Diagnostic Process ◽  
Total Resistance ◽  
System Operation ◽  
Factors Influencing ◽  
Resistance Torque ◽  
The Moment ◽  
Engine Crankshaft

Engine crankshaft driving by the starter is characterised as a diagnostic process. The article discusses the working conditions of the electric starter when driving the engine crankshaft in terms of the equilibrium of the engine resistance torque and the moment of force generated by starting system. The resistance sources in the internal combustion engine were characterized and factors influencing them were discussed, its components and dependencies allowing for their determination were indicated. The variability of the engine resistance torque in the cycle of its operation as well as the variability of the torque and rotational speed of the crankshaft in the process of propelling the shaft are indicated. The stand and the methodology for testing the engine's internal combustion engine and the influence of the temperature and power of the starting system on registered start signals are presented. The cause and effect relationships of the engine resistance torque and the features – parameters of the starting system operation were indicated. It was shown that the values of signals recorded during the crankshaft driving have the features of engine diagnostic parameters in the aspect of the combustion chamber tightness and the total resistance of the internal combustion engine.

scholarly journals Less wear on the piston skirts of internal combustion engines

2020 ◽  
Vol 21 (3) ◽  
pp. 175-180
Author(s):  
Arthur R. Asoyan ◽  
Alexander S. Gorshkov ◽  
Ani H. Israelyan
Keyword(s):  
Internal Combustion Engine ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Surface Plastic ◽  
Combustion Engines ◽  
Piston Cylinder ◽  
Operational Life ◽  
Piston Skirts

A significant proportion of mechanical losses in internal combustion engines accounted for mechanical losses in the cylinder-piston group. Depending on the operating modes of the internal combustion engine, contact interaction in the piston-cylinder pair is possible, which leads to wear of the working surfaces of the resource-determining elements and a decrease in the operational life of the power unit as a whole, in connection with which the reduction of friction losses in the internal combustion engine elements and the piston - cylinder liner coupling in particular is relevant. Both domestic and foreign researchers are engaged in the solution of the above described problems, various profiles of pistons, methods of calculating the parameters of the oil layer are proposed, but the practical state of the issue determines the relevance of research in this direction. The paper considers the possibility of reducing the wear of piston skirts by reducing the contact surface in conjugation and providing an oil film in the friction zone, regardless of engine operating conditions. This opportunity is realized by forming a certain macro profile on the working surface of the piston skirt. The formation of the macrorelief was carried out by means of surface plastic deformation, with the reciprocating movement of a spherical tool on the machined surface.

scholarly journals Assessment of the starter motor system use powered by capacitive power sources on internal combustion engine

2021 ◽  
Vol 341 ◽  
pp. 00054
Author(s):  
Anton Bijaev ◽  
Kristina Ishutochkina
Keyword(s):  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Power Sources ◽  
Lead Battery ◽  
System Use ◽  
Partial Displacement ◽  
Electric Supply ◽  
Engine Start

The main power source of modern electric start systems for internal combustion engines is an acid-lead battery. Existence chemical reactions, which occur in between battery electrolyte and lead plates may be causes problems with it exploitation. For a many reasons, its operation requires a lot of labor, especially in cold conditions. In this regard, it was proposed to use a capacitor system electric supply taking in view its discharge characteristics. Electrolytic capacitors and supercapacitors are sources of temporary charge storage and have optimal properties for their use in the engine start system as a partial displacement of the acid-lead battery, against the background of its some negative qualities. The article deals with the evaluation and comparison of the electric motor start system from capacitors and supercapacitors, as well as the possibility of their implementation on a mobile machine equipped with ICE.

Factors Influencing Rope Force of Recoil Starter

2012 ◽  
Vol 220-223 ◽  
pp. 494-498
Author(s):  
Yu Wei Chen ◽  
Sheng Ji Liu ◽  
Jian Wang
Keyword(s):  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Friction Resistance ◽  
Factors Influencing ◽  
Resistance Torque ◽  
Resistance Moment ◽  
Compression Resistance ◽  
Important Design

Rope force of recoil starter is an important design parameter for starting safety. This paper analyzes the starting resistance torque of an internal combustion engine, and then proposes the appropriate calculation methods of friction resistance moment, compression resistance moment and inertia resistance moment. Taking several types of internal combustion engines for example, this paper analyzes the main factors influencing rope force, and then draws the conclusion that displacement and ambient temperature are the key to the rope force. The work provides the basis for the design and inspection of recoil starter.

The Use of Short-Term Compressed Air Supercharging in a Combustion Engine with Spark Ignition

2021 ◽  
Vol 18 (2) ◽  
pp. 8704-8713
Author(s):  
Jarosław Janusz Mamala ◽  
K. Praznowski ◽  
S. Kołodziej ◽  
G. Ligus
Keyword(s):  
Driving Force ◽  
Negative Impact ◽  
Combustion Engine ◽  
Spark Ignition ◽  
Compressed Air ◽  
Acceleration Process ◽  
Combustion Engines ◽  
Short Term ◽  
Drive Unit ◽  
The People

The powertrain is a very important subassembly in a car and is responsible not only for the automotive industry’s impact on the environment but also for the safety of people travelling by car and performing overtaking manoeuvres and joining traffic. In general, the powertrain is a combination of the drive unit and drive transmission, wherein the drive unit is responsible for the available driving force in the car’s wheels and for the car’s ability to accelerate when the throttle pedal is rapidly pressed at a constant gearbox ratio. The availability of the driving force reserve in the powertrain is the most important issue for the reason of safety of the people travelling by car. In the case of drive unit what they are of the combustion engines, the rapid pressing of the throttle pedal in the car acceleration process leads to a temporary deficiency in the driving force and in the powertrain’s output. The deficiency in the driving force has a negative impact on acceleration and driving comfort. In this paper, the authors assessed and analysed two different short-term compressed air supercharging systems for combustion engines with air supplied from a high-pressure tank. The analysis covered the response of the combustion engine with spark ignition to the gradual increase in pressure in the air-intake system. The assumption is that the applied short-term compressed air supercharging system could improve the driving force during the phase of the engine’s increasing crankshaft rotational speed. This helps to achieve the improved passenger car acceleration dynamics, depending on the supercharging method and throttle pedal exertion. When analysing the car’s acceleration dynamics, expressed by the shorter time of increasing the longitudinal speed from initial to final, it was possible to shorten the acceleration time. It is also possible to observe an improved driving force behaviour, especially during the first phase of acceleration.

A General Rezoning Technique for KIVA3V Internal Combustion Engines CFD Simulations

2010 ◽  
Author(s):  
Randy P. Hessel ◽  
Ettore Musu ◽  
Salvador M. Aceves ◽  
Daniel L. Flowers
Keyword(s):  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Ad Hoc ◽  
National Laboratory ◽  
Internal Combustion ◽  
Computational Time ◽  
Combustion Engines ◽  
Combustion Chambers ◽  
Time Step ◽  
Engine Cycle

A computational mesh is required when performing CFD-combustion modeling of internal combustion engines. For combustion chambers with moving pistons and valves, like those in typical cars and trucks, the combustion chamber shape changes continually in response to piston and valve motion. The combustion chamber mesh must then also change at each time step to reflect that change in geometry. The method of changing the mesh from one computational time step to the next is called rezoning. This paper introduces a new method of mesh rezoning for the KIVA3V CFD-combustion program. The standard KIVA3V code from Los Alamos National Laboratory comes with standard rezoners that very nicely handle mesh motion for combustion chambers whose mesh does not include valves and for those with flat heads employing vertical valves. For pent-roof and wedge-roof designs KIVA3V offers three rezoners to choose from, the choice depending on how similar a combustion chamber is to the sample combustion chambers that come with KIVA3V. Often, the rezoners must be modified for meshes of new combustion chamber geometries to allow the mesh to successfully capture change in geometry during the full engine cycle without errors. There is no formal way to approach these modifications; typically this requires a long trial and error process to get a mesh to work for a full engine cycle. The benefit of the new rezoner is that it replaces the three existing rezoners for canted valve configurations with a single rezoner and has much greater stability, so the need for ad hoc modifications of the rezoner is greatly reduced. This paper explains how the new rezoner works and gives examples of its use.

Investigating Fuel Condensation Processes in Low Temperature Combustion Engines

2014 ◽  
Author(s):  
Lu Qiu ◽  
Rolf D. Reitz
Keyword(s):  
Low Temperature ◽  
Combustion Engine ◽  
Phase Region ◽  
Low Temperature Combustion ◽  
Combustion Engines ◽  
Two Phase ◽  
Temperature Combustion ◽  
Real Gas Effects ◽  
Unburned Hydrocarbons ◽  
Late Stages

Condensation of gaseous fuel is investigated in a low temperature combustion engine fueled with double direct-injected diesel and premixed gasoline at two load conditions. Possible condensation is examined by considering real gas effects with the Peng-Robinson equation of state and assuming thermodynamic equilibrium of the two fuels. The simulations show that three representative condensation events are observed. The first two condensations are found in the spray some time after the two direct injections, when the evaporative cooling reduces the local temperature until phase separation occurs. The third condensation event occurs during the late stages of the expansion stroke, during which the continuous expansion sends the local fluid into the two-phase region again. Condensation was not found to greatly affect global parameters, such as the average cylinder pressure and temperature mainly because, before the main combustion event, the condensed phase was converted back to the vapor phase due to compression and/or first stage heat release. However, condensed fuel is shown to affect the emission predictions, including engine-out particulate matter and unburned hydrocarbons.

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