This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Windage Tray Design Comparison Using Crankcase Breathing Simulation
Technical Paper
2013-01-0580
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
The conflicting requirements of better fuel economy, higher performance and lower emissions from an automobile engine have brought many new challenges that require development teams to look beyond conventional test and seek answers from simulations. One of the relatively unexplored areas of development where frictional losses haven't been completely understood is the flow in the crankcase. Here computational engineering can play a significant role in analyzing flow field in a hidden and complex region where otherwise testing has serious limitations.
Flow simulation in the crankcase poses significant complexity and provides an opportunity to enhance the understanding of underlying physics by using multi-physics analyses tools available commercially. In this study, air space under the piston and above the oil level in oil pan is simulated. It is known that bay-to-bay breathing and windage holes account for considerable amount of power losses in the crankcase. Therefore, this study is intended to (but not limited to) the estimation of pumping losses (i.e., power required for piston to overcome the resistance offered by air in the crankcase) in addition to gaining insight into flow field to improve breathing between bays. The simulation is carried out with air as fluid and oil is kept stationary to maintain a constant level in the oil pan. Various meshing and mesh moving techniques were employed. This includes, arbitrary sliding interface (ASI) of counter weights and mesh morphing to replicate piston motion. Time dependent momentum and energy equations were solved for air as compressible media.
The study found that one of the major components that can have significant effect in reducing pumping losses and oil aeration is the design of windage tray. The windage tray design can be used for effective oil drainage along with reducing the splashing and sloshing of oil in the crankcase. The openings in the windage tray can be optimized for location and size so as to reduce pumping losses as well as oil aeration. This will have positive impact on engine power as well as fuel efficiency. Windage hole size, number and location also helps in determining the flow through drainbacks, and consequently affect the tuning of PCV and makeup air valves.
Recommended Content
| Technical Paper | Fuel Efficiency Screening Tests for Automotive Engine Oils |
| Technical Paper | The Impact of Organomolybdenum Compounds on the Frictional Characteristics of Crankcase Engine Oils |
Authors
Citation
Iqbal, O. and Arora, K., "Windage Tray Design Comparison Using Crankcase Breathing Simulation," SAE Technical Paper 2013-01-0580, 2013, https://doi.org/10.4271/2013-01-0580.Also In
References
- Heywood , J. B. Internal Combustion Engine Fundamentals McGrawHill 1988
- Koch , F. , Haubner , F. , and Orlowsky , K. Lubrication and Ventilation System of Modern Engines - Measurements, Calculations and Analysis SAE Technical Paper 2002-01-1315 2002 10.4271/2002-01-1315
- Totten , G. E. , Bishop , R. J. , Suzuki , R. , and Tanaka , Y. Air entrainment - How it Happens, How to Avoid it Hydraulics and Pneumatics 39 41 2001
- Ranganathan , R. Engine Crankcase Pumping Flow Model SAE Technical Paper 1999-01-0215 1999 10.4271/1999-01-0215
- Deighan , T. and Zuhdi , N. Crankcase Flow Modeling for a Racing Motorcycle Engine SAE Technical Paper 2007-01-0266 2007 10.4271/2007-01-0266
- Troxler , P. Cool Design at Harley-Davidson Motor Company http://www.cd-adapco.com/press_room/dynamics/19/harley.html
- Pierson , S. Post Processing JLR Powertrain CFD Using Ensight Ensight http://www.ensight.com/images/stories/pdf/Ensight17_10_06.pdf
- Edelbauer , W. , and Diemath , A. Simulation of the Ventilation Losses in the Crankcase of an Internal Combustion Engine Progress in Computational Fluid Dynamics 10 1 1 18 2010
- Thumheer , T. , Soltic , P. The polytropic volume method to detect engine events based on the measured cylinder pressure Control Engineering Practice 20 3 March 2012
- StarCCM+ version 6.02.007 documentation