Technology Development to Improve Jatco CVT8 Efficiency

Paper #:
  • 2013-01-0364

Published:
  • 2013-04-08
Citation:
Shimokawa, Y., "Technology Development to Improve Jatco CVT8 Efficiency," SAE Technical Paper 2013-01-0364, 2013, https://doi.org/10.4271/2013-01-0364.
Author(s):
Affiliated:
Pages:
8
Abstract:
This paper explains the developed technologies for improving the efficiency of Jatco CVT8 and the procedures followed in developing and verifying them.CVT8 has 40% less mechanical loss than the existing base CVT and contributes substantially to improving the fuel economy of the new 2013 Nissan Altima 2.5L.First, a loss analysis of the existing base CVT revealed that the largest loss factors were the belt-pulley system, oil pump and fluid churning. They were reduced by downsizing the oil pump and lowering the line pressure, followed by optimization of the belt shape and then reduction of churning loss.Reducing churning loss is not so simple because fluid dispersion also functions to lubricate some parts. Computational fluid dynamics (CFD) was used to design the baffle plate shape and the fluid level. An experiment was then conducted to visualize the fluid behavior, and the results were used to refine the baffle plate shape and adjust the fluid level so as to reduce churning loss while maintaining product quality.A method was adopted for verifying the fuel economy improvement using motor benches with the HILS. Using this method, a relative evaluation was made of the energy efficiency of the existing base CVT and CVT8 for the same engine and vehicle model during operation under regulatory test driving modes. The results showed that CVT8 contributes to a fuel economy gain of more than 10% compared with the existing unit.
Access
Now
SAE MOBILUS Subscriber? You may already have access.
Buy
Select
Price
List
Download
$28.00
Mail
$28.00
Members save up to 42% off list price.
Share
HTML for Linking to Page
Page URL

Related Items

Training / Education
2018-03-29
Technical Paper / Journal Article
2011-05-17
Training / Education
2007-03-01
Technical Paper / Journal Article
2011-08-30
Event
2018-04-10
Article
2017-07-26
Technical Paper / Journal Article
2009-06-15
Training / Education
1997-05-29
Training / Education
2018-05-07
Technical Paper / Journal Article
2011-08-30