Connecting Rod Bearing Operation with Aerated Lube Oil

Maassen, Franz; Koch, Franz; Pischinger, Franz

doi:10.4271/981404

Cited by 21 publications

(8 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Under these conditions, this calculation substantiates the previous approaches used by Meernik [1], correlation equation for rotating tubes obtained by Ito and Nambu [7]. The results indicate that viscous drag Nemoto et al [2] and Maassen et al [3] where the viscous forces were neglected in the minimum pressure calforces may need to be considered for an accurate prediction of the minimum pressure inside the rotating transfer culation. For other operating conditions (diVerent values for R min , bore diameter, rotational speed, average velocpassage.…”

Section: Notationsupporting

confidence: 89%

“…í oil viscosity (Pa s) r oil density (kg/m3) ¼ scalar potential of centrifugal force a c acceleration (m/s2) [equation (8) [2] and Maassen et al [3]. These studies predicted p atm =1.013 25 bar the minimum static pressure occurring inside a rapidly p g static gauge pressure =p Õp atm rotating transfer passage due to the centrifugal force P modi ed pressure, de ned in equation (9) resulting from the crankshaft rotation.…”

Section: Notationmentioning

confidence: 99%

See 1 more Smart Citation

Technical Note: Viscous contribution to minimum static pressure in a rapidly rotating transfer passage

Papa

Kripesh

Keith

et al. 2001

Proceedings of the Institution of Mechanical Engineers, Part D:

View full text Add to dashboard Cite

This paper describes a one-dimensional model that predicts the minimum static pressure in a rotating transfer passage taking into account both the centrifugal and the viscous forces, the latter having been neglected in previous studies. The minimum pressure is important as it determines the engine lubricating capacity and whether aero-cavitation may occur in the passage. The ow is considered laminar and the uid is incompressible and Newtonian with constant viscosity. The current model predicts a lower minimum pressure within the transfer passage due to the inclusion of the viscous forces in the model.

show abstract

Section: Notationsupporting

confidence: 89%

Section: Notationmentioning

confidence: 99%

Technical Note: Viscous contribution to minimum static pressure in a rapidly rotating transfer passage

Papa

Kripesh

Keith

et al. 2001

Proceedings of the Institution of Mechanical Engineers, Part D:

View full text Add to dashboard Cite

show abstract

“…Oil groove milled in the strip bubble formation in the oil, leading to a potential cavitation occurrence [4].…”

Section: Groove Milling Operationmentioning

confidence: 99%

Bronzinas Centrais com Canal de Óleo Otimizado para Redução de Perdas na Bomba de Óleo

Ferreira¹,

Silva²

2021

Blucher Engineering Proceedings

View full text Add to dashboard Cite

The main focus of ROTA 2030 program is to identify how to enable further fuel savings giving the efforts implemented by Inovar-Auto, e.g. at crankshaft area.In a way to reduce friction losses and fuel consumption, OEMs are adopting features like variable oil pumps, new crankshaft oil drilling (e.g. one main bearing feeding two connecting rod bearings) and new configuration for the main bearings oil grooves. Usually a full groove (180°) is specified for the upper main bearing once it delivers the necessary oil flow and pressure to the connecting rod bearings with a cost effective manufacturing process. By adopting a partial groove configuration, which can typically vary from 90° to 170°, the overall oil flow to the bearings can be reduced once side flow is reduced. Such design solution enables the oil pump to work more efficiently specially when in a variable flow design. The challenge remains on keeping Minimum Oil Film Thickness (MOFT) safe to ensure robustness and durability. However, the adoption of partial grooves increases manufacturing costs considerably.Using CFD simulation and dynamometer engine test, a new optimized main bearing oil groove was developed, which combines the reduced flow of the partial oil groove with the manufacturability of a full groove.

show abstract

“…Aeration in the rotating groove limits the pressure level, and the released air disturbs the oil flow; as a consequence, oil starvation occurs in the bearing. Maassen et al [4] studied 'aerationcavitations' in the big-end bearing, which are mainly due to the insufficient pressure level. Such studies are based on the steady state flow assumption.…”

Section: Introductionmentioning

confidence: 99%

Prediction of transient lubricating oil flows within the connecting-rod of a diesel engine

2011

View full text Add to dashboard Cite

This paper develops Aa computer program for the unsteady flow analysis of diesel engine lubrication systems. The possibility of cavitations developing in the big-end bearing groove due to the reciprocating motion of the connecting rod is investigated at the designed running speeds. The flow passage geometry especially the head loss coefficients of the bearing grooves s affects the minimum values of the head and the point when the development of the cavitations is initiated As the loss coefficient at the bigend increases and that of the small-end decreases, then the cavitations can be initiated. An orifice can be used to suppress the development of the cavitations and the diameter ratio and the location needs to be carefully selected to avoid unnecessary pressure loss. The channel size in the connecting rod is also an important parameter for optimization of the overall lubrication system; as the pipe diameter decreases, the minimum head increases and suppresses the cavitations from developing The minimum head always appears at the trailing groove of the big-end bearing.

show abstract

Connecting Rod Bearing Operation with Aerated Lube Oil

Cited by 21 publications

References 1 publication

Technical Note: Viscous contribution to minimum static pressure in a rapidly rotating transfer passage

Technical Note: Viscous contribution to minimum static pressure in a rapidly rotating transfer passage

Bronzinas Centrais com Canal de Óleo Otimizado para Redução de Perdas na Bomba de Óleo

Prediction of transient lubricating oil flows within the connecting-rod of a diesel engine

Contact Info

Product

Resources

About