Gas Escape from Combustion Chamber to Crankcase, Analysis of a Set of Parameters Affecting the Blow by

Delprete, Cristiana; Bisha, Arian; Selmani, Erjon

doi:10.1007/978-3-319-90893-9_49

Cited by 4 publications

(3 citation statements)

References 15 publications

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“…The number of parameters affecting the sealing efficiency of a ring pack is high, so it would be extremely difficult to consider all of them in the space of a scientific paper, hence the decision to study the phenomenon by splitting the parameters. In previous works [20], the authors investigated the effect of speed, load and inter-ring volumes, on the sealing capacity of a ring pack, while in this work extending the study to other parameters has been proposed. First of all, it was decided to simulate the effect of the top and second ring gaps.…”

Section: Modeling Approach For Ring Dynamicsmentioning

confidence: 99%

Gas escape to crankcase: impact of system parameters on sealing behavior of a piston cylinder ring pack

Delprete

Selmani

Bisha

2019

Int J Energy Environ Eng

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Internal combustion engines are the generators of energy for many transportation applications, but they still have an overall low efficiency due to mechanical and thermal losses. The combustion chamber is the core element of the engine and it ought to be perfectly sealed; however, some of the gas leaks toward the crankcase due to imperfect sealing of the rings. This leakage is known as blow-by and affects efficiency, correct lubrication and emissions. The aim of this paper was to understand, in a more detailed way, how some parameters could affect the sealing efficiency of a ring pack. In particular, ring gaps, ring masses and elastic properties, and ring static twists, were varied from the original and investigated for their influence on the inter-ring dynamics and sealing efficiency. The problem, referred to a turbo diesel engine, was formulated in terms of motion equations for the rings and gas equations for the inter-ring crevices, and solved in © Ricardo RINGPAK solver. The results were compared with the original design and with the reference literature. These results confirm that ring gaps and ring unstable motion have an important role in the phenomenon of gas blow-by. In addition, the second ring emerged to have a more important role on the blow-by reduction with respect to the top ring. However, this phenomenon is complex due to the interaction of several parameters, not all of which were included in this study. Nevertheless, these findings can already be taken into account for further studies or experimental investigations. List of symbols ARing face area subjected to a given pressure, m 2 A gap Gap area, m 2 A p Piston acceleration, m/s 2 BRing radial width, m BDC Bottom dead center * Erjon Selmani

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Section: Modeling Approach For Ring Dynamicsmentioning

confidence: 99%

Gas escape to crankcase: impact of system parameters on sealing behavior of a piston cylinder ring pack

Delprete

Selmani

Bisha

2019

Int J Energy Environ Eng

Self Cite

View full text Add to dashboard Cite

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“…In reference [17] Authors have proposed a similar analysis but the focus was on other parameters or the engine. In the present work the problem will be extended to the effect of the bore distortion on the ring pack performance.…”

Section: Simulationmentioning

confidence: 99%

Cylinder liner deformation orders and efficiency of a piston ring-pack

2019

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One of the several losses of a combustion chamber is the gas leakage toward the crankcase due to imperfect sealing of the rings. It is commonly known as blow by and it affects efficiency and emissions. The paper initially describes a bibliographic review of the phenomenon, together with the equations of the system. A typical piston ring pack for internal combustion engine is proposed to be analysed and solved using ©Ricardo RINGPAK Solver. A specific issue such as Bore distortion orders were used to investigate the sealing capacity of the ring-pack in terms of ring dynamics, inter-ring pressures and mass flows. Bore distortion orders and their magnitude showed to affect the ring pack behavior. Order zero distortion resulted to be the most important order due to the highest amount of gas lost in the crankcase, while orders three and four resulted to generate high blow-by values, even if their magnitude of distortion is lower in comparison to other orders.

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“…In Ref. [25] Authors have proposed a similar analysis where the focus was on other parameters or the engine. In the present work, the problem was extended to the effect of the bore distortion on the ring pack performance.…”

Section: Simulationmentioning

confidence: 99%

Simulation of the cylinder bore distortion and effect on the sealing capacity of the ringpack

2019

Self Cite

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One of the several losses of a combustion chamber is the gas leakage toward the crankcase due to imperfect sealing of the rings, it is commonly known as blow-by and it affects efficiency and emissions. One important factor affecting it is the distorted cylinder bore. The paper describes the equations that rule the blow-by phenomenon in terms of ring and gas dynamics, subsequently, the bore distortion of the cylinder was obtained and its orders calculated through Fourier series. The ringpack capacity in the distorted bore cylinder was then analysed using ©Ricardo RINGPAK Solver. Order zero distortion resulted to be the most important order due to the highest amount of gas lost in the crankcase. Orders one and two didn't showed significant differences from the non-distorted bore case, while orders three and four resulted in high blow-by values, even if their magnitude of distortion was lower in comparison to other orders. The ring pack behavior showed to be affected by bore distortion and its magnitude, however, the blow by phenomenon showed to depend also on other factors in a complex manner.

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Gas Escape from Combustion Chamber to Crankcase, Analysis of a Set of Parameters Affecting the Blow by

Cited by 4 publications

References 15 publications

Gas escape to crankcase: impact of system parameters on sealing behavior of a piston cylinder ring pack

Gas escape to crankcase: impact of system parameters on sealing behavior of a piston cylinder ring pack

Cylinder liner deformation orders and efficiency of a piston ring-pack

Simulation of the cylinder bore distortion and effect on the sealing capacity of the ringpack

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