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Modeling of internal combustion engine thermodynamics, valve dynamics and valve flow

Thesis (MScEng)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: In the design or modification of internal combustion (IC) engine
components, the South African Automotive industry has always relied on
either design by mother companies or quasi-empirical design methods.
These methods have restricted the performance and reliability of local
designs.
A personal computer based model of four stroke engine operation has
been developed as a rapid and cost-effective aid to users who wish to
determine the performance of an engine with reasonable accuracy before
dynamometer testing is possible. This model consists of a thermodynamic
model of combustion and gas exchange linked to a manifold flow model.
Accompanying this is a simulation of valve flow and a cam dynamic model,
enabling full assessment of the optimum cam profiles and valve angles for
various automotive engine configurations.
The accuracy of these models has been verified by comparison with a set
of engine dynamometer tests. The models have also been used with great
success in local and international development projects in conjunction with
local automotive manufacturers. In particular, two engine upgrade projects
have been successfully completed, in which the program was used to aid
the design of inlet manifolds, the selection of camshafts, and the selection
of compression ratios. / AFRIKAANSE OPSOMMING: In die ontwerp of modifikasie van binnebrandenjin-komponente het die
Suid-Afrikaanse Motorbedryf gewoonlik staatgemaak op óf die ontwerpe
van die moedermaatskappy óf is van quasi-empiriese ontwerp metodes
gebruik gemaak. Hierdie metodes het die werkverrigting en uithouvermoë
van plaaslike ontwerpe beperk.
'n Rekenaar model wat die werking van 'n vierslagenjin moduleer, is
ontwikkel as 'n vinnige en koste effektiewe hulpmiddel vir ontwerpers om
'n redelike akkurate voorspelling van enjin werkverrigting te verkry, voordat
dynamomotor toetswerk moontlik is. Die model bestaan uit 'n
termodinamise model vir ontbranding en die gas uitruilproses, gekoppel
aan 'n spruitstuk vloeimodel. Die model word saam met 'n simulasie van
klepvloei en 'n nok dinamiese model gebruik, wat toelaat dat 'n goeie
raming van die optimum nokprofiele en klephoeke gemaak kan word vir
verskeie automobielenjin konfigurasies.
Die akuraatheid van hierdie modelle is bevestig deur die vergelyking van
simulasie resultate met 'n omvangreike stel enjin dynamomotor toetse.
Die modelle is ook met groot sukses in verskeie plaaslike en
internasionale ontwikkelingsprojekte, in samewerking met die plaaslike
motorbedryf, gebruik. In besonder is twee enjinontwikkelingsprojekte
suksesvol voltooi, waarin die simulasie program gebruik is om die ontwerp
van die inlaat spruitstuk, die keuse van nokasse en die keuse van
drukverhouding te vergemaklik.

Identiferoai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:repository.sun.ac.za:10019.1/52939
Date12 1900
CreatorsWilliams, Paul Ngcebo Tudor
ContributorsTaylor, A. B., Thiart, G. D., Stellenbosch University. Faculty of Engineering. Dept. of Mechanical NS Mechatronic Engineering.
PublisherStellenbosch : Stellenbosch University
Source SetsSouth African National ETD Portal
Languageen_ZA
Detected LanguageUnknown
TypeThesis
Format205 P. : ill.
RightsStellenbosch University

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