An Integrated Design Approach for Robust Engine Development: A Case Study 2005-26-002

The intensifying needs demanded by the legislation, shorter product development cycle and utmost attention given to durability aspects of product have surfaced out various complex technical areas in the field of engine out emissions, FIP hydraulics, computational fluid dynamics, thermal analysis and structural design of components.

This paper is an endeavour to present the gesticulations used in one of the upgradation program for improving engine performance to meet desired emission and performance levels with the help of simulation tools and statistical database.

The single cylinder air cooled D. I. engine under development is explored first for possible improvements in induction and exhaust systems, FIP performance and combustion package, valve train layout, cylinder head design, fin layout and pattern, features for improvement in oil consumption, modifications in engine block and crankcase etc.

Simulation codes are used for prediction of engine performance, emissions, FIP hydraulics characteristics etc. in order to make the product technically and economically viable. Experimental verification is done wherever possible and results presented.

The baseline simulation of engine performance for parameters like power, bsfc and various efficiencies along with FIP characteristics are confirmed in good agreement with experimental results.

A steady state, conjugate thermal analysis is carried out by using STAR - CD CFD code for base line and modified cylinder head. Emphasis was given to get uniform temperature and velocity distribution and to improve cooling of cylinder head. Temperature distribution data is also acquired during test trails on base line cylinder head for supporting the simulation results. The CFD analysis was carried out with conjugate heat transfer option where the convection and conduction heat transfer modes are accounted simultaneously. The flow field and thermal field results are studied for detail analysis. With the improved design of cylinder head, the maximum temperature of air in the fluid domain is found 3 % greater compared to baseline cylinder head highlighting the improved cooling efficiency and the same is verified on the real engine with modified cylinder head.