Knock Mitigation by Means of Coolant Control 2019-24-0183
The potentiality of knock mitigation by means of the control of the coolant flow rate is investigated.
As a first step, the dynamic behavior of the wall temperature in response to a sudden variation of the coolant flow rate is analyzed experimentally in a small displacement, 4-valve per cylinder SI engine, which is equipped with an electrically driven pump.
Subsequently, the influence of the wall temperature on knock onset is analyzed through a zero-dimensional model and the Livengood and Wu integral.
Finally, an experimental activity on the engine test bed is carried-out in order to evaluate the influence of the coolant flow rate and of the engine inlet coolant temperature on the knock phenomenon.
Results show that, even though a retarded spark advance and a mixture enrichment are not avoidable in the early stage of knock onset, a cooling control can help reducing the time of use of these fuel consuming strategies in the case of prolonged high-load conditions.
Diego Perrone, Luigi Falbo, Teresa Castiglione, Sergio Bova
Università della Calabria
14th International Conference on Engines & Vehicles