| Pub. Date | : Feb, 2020 |
|---|---|
| Product Name | : The IUP Journal of Mechanical Engineering |
| Product Type | : Article |
| Product Code | : IJME40220 |
| Author Name | : K R Gawande, Sameer Mahamandre |
| Availability | : YES |
| Subject/Domain | : Engineering |
| Download Format | : PDF Format |
| No. of Pages | : 11 |
The 250cc engine is a well-known mechanical component used for power generation but subjected to very high temperature and thermal stresses. Therefore, cooling of engine is essential. For this purpose, there are two options, i.e., using either liquid cooling system or air cooling system. Nowadays, many of the automotive industries prefer liquid cooling system for higher cc engine, but this system has some drawbacks which can be overcome using air-cooling system (fins). An air-cooled engine releases heat to the atmosphere through the mode of forced convection; to facilitate this, fins are provided on the outer surface of the cylinder. The paper reviews the design and thermal analysis of 250cc engine cylinder fins using different materials to replace liquid cooling system.
Extended fins are well known for enhancing the heat transfer in IC engines. However, liquid-cooling system enhances heat transfer better than air-cooling system. The construction of air-cooling system is very simple. Therefore, it is important for an air-cooled engine to utilize the fins effectively to obtain uniform temperature in the cylinder periphery. Air-cooled engines are phased out and are replaced by water-cooled engines which are more efficient, but almost all two-wheelers use air-cooled engines, because air-cooled engines are the only option due to some advantages like lighter weight and lesser space requirement. The heat generated during combustion in IC engine should be maintained at higher level to increase thermal efficiency, but to prevent the thermal damage, some heat should be removed from the engine. Extended surfaces (fins) are one of the heat exchanging devices that are employed to increase the heat transfer on engine cylinder. It is necessary to analyze the heat transfer rate of the fins. Experiments have been made to increase fin efficiency by changing fin material, climatic conditions around fins, varying pitch of the fins using perforations and notches in fins and fin geometry. A fin is a surface that extends from an object to increase the rate of heat transfer to or from the environment by increasing convection. Extensions on the finned surfaces are used to increase the surface area of the fin in contact with the fluid flowing around it which further increases the rate of heat transfer from the base surface as compared to fin without extensions provided to it. Types of extensions provided on fin are: rectangular, trapezium and triangular extensions. The amount of conduction, convection or radiation of an object determines the amount of heat it transfers. Heat transfer rates can be increased by increasing (1) the temperature gradient between the object and the environment; (2) convection coefficient; and (3) surface area of the object. Considering the feasibility and economical way of increasing the heat transfer rate, option 3 is more practicable. The paper reviews the design and thermal analysis of 250cc engine cylinder fins using different materials to replace liquid cooling system.
Heat engine, Fins, Necessity of cooling, Selection of material, Analysis