Study of a Two-Degree-of-Freedom Exhaust System

900164

02/01/1990

Event
International Congress & Exposition
Authors Abstract
Content
An investigation was conducted into pressure pulsation in the exhaust port, which greatly affects volumetric efficiency and engine performance.
From experiments using a single blow-down generator, it was established that the amplitude of the pressure pulsation increases as the manifold branch is lengthened and that large negative pressure synchronized with the timing of valve overlap can be obtained if a proper branch length is used.
The performance of a 2ℓ test engine was optimized by varying the length of both the manifold branches and front pipe forks. It was found that whereas front pipe fork length affects engine performance over only a narrow range of engine speed, optimizing manifold branch length results in a considerable improvement over a wide engine speed range.
In the course of optimizing the exhaust pipe manifold length of this two-degree-of-freedom exhaust system, abnormal exhaust noises were emitted at specific engine speeds during deceleration. These were greatly reduced by modifying the branch and fork junction configurations.
Meta TagsDetails
DOI
https://doi.org/10.4271/900164
Pages
8
Citation
Hokazono, Y., Iezuka, I., Konomi, T., Nohira, H. et al., "Study of a Two-Degree-of-Freedom Exhaust System," SAE Technical Paper 900164, 1990, https://doi.org/10.4271/900164.
Additional Details
Publisher
Published
Feb 1, 1990
Product Code
900164
Content Type
Technical Paper
Language
English