Cooling System of Engine

ENGINE COOLING SYSTEM

By

PUNEET SAXENA

NEW HOLLAND, INDIA

Object of the Paper : To analyse the cooling system of the engine in order to achieve the optimum performance for efficient working of engine.

A B S T R A C T

This paper explores the technical aspects involved in the designing of the cooling systems for the tractor. The heat carried by the cooling water jacket is 30% of the total energy produced in the engine. A small but significant percentage of the power is being consumed by the fan and the pump, which should be judiciously, combined with the suitable radiator to achieve not only the efficient performance of the engine but also the cost effectiveness.

In tractors usually the air cooled radiators work in association with the fan which must provide the airflow requirements of the cooling system against the pressure loss, operate effectively and quietly and while being fitted in allocated space. These parameters must be considered to satisfy the requirement of airflow, fan diameter and fan speed. The purpose of this paper is to apply the available data efficiently towards the solution of the problem. By applying the Angular Momentum Equation to a fixed control volume the inlet and outlet velocity polygons are developed to achieve the power consumed by the fan along with the resulted volume flow rate.

Radiators are heat exchangers provided to help control engine operating temperatures. Operating fluids are engine coolant on the inside and ambient air on the outside. In the radiator system out of engine coolant and air, air is the minimum fluid. The critical parameter for tractors is the Air-to-Boil Temperature (ATB) which determines the selection of the radiator in tractors. The engine power determines the heat exchange required from the specific radiator. Further the parameters – Mixed or Unmixed flow, Boiling Temp., Ambient Temp., ATB and the Air inlet temp. are used to determine the Overall Heat Transfer Coefficient to the corresponding volume flow rate of the air. The selection is made for the proper combination of the volume flow rate (affecting the power consumed by the fan) and the overall heat transfer coefficient (determining the cost of the radiator). The water flow rate is being used to calculate the effectiveness of the radiator. Hence the combination of the Engine Horse Power along with the Water Flow Rate and Volume Flow Rate from fan can be used to get the effective cooling. The radiator is being tested for ATB on the tractor both at the rated and peak torque.

This study is being used to build the software program for determining the Radiator and Fan specification for the effective cooling in the tractor.