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An innovative control strategy, which is based on the Robust Model Predictive Control (MPC) methodology, was developed with the purpose of optimizing the engine thermal management; the proposed control strategy adjusts the coolant flow rate by means of an electric pump, in order to bring the cooling system to operate around the onset of nucleate boiling. In the present paper, the advantages of the proposed cooling approach are evaluated along the NEDC homologation cycle, which was both simulated and replicated by means of laboratory tests; the latter include coolant, lubricant and wall temperature measurements. Special attention was reserved to the warm-up period. The case considered herein is that of a Spark Ignition engine, about 1.2 dm3 displacement, and a comparison with standard crankshaft driven pump is included.

In this paper, we propose a novel control architecture for dealing with the requirements arising in a cooling system of an ICE. The idea is to take advantage of the joint action of an electric pump and of an ad-hoc regulation module, which is used to determine adequate flow rates despite engine speeds. Specifically, a robust Model Predictive Control approach is exploited to take care formally of input/output constraints and disturbance effects of the resulting lumped parameter model of the engine cooling system, which incorporates the nucleate boiling heat transfer regime. Numerical simulations and test rig experimental data are presented. The results achieved show that the proposed control scheme is capable of providing effective and safe cooling while mitigating disturbance effects and minimizing coolant flow rates when compared with the action pertaining to standard crankshaft driven pumps.

The paper illustrates a zero-dimensional dynamic model which was developed in the MATLAB®/Simulink environment to predict thermal transient of an automotive cooling system. In particular, the rapid switch-off of an internal combustion engine which was operated for a prolonged time at high speed under full load was investigated. In this condition, significant vapour formation and, consequently, pressure rise within the cooling circuit can arise, because of the sudden heat transfer from the high temperature head metal to the coolant contained in the cylinder head passages. The proposed model allows predictions of the vaporized mass of coolant as well as of the pressure evolution within the cooling circuit. The simulations results were compared with experimental tests carried out on a production 4-cylinder, MPI small S.I. engine, 1.2 dm3 displacement, and the agreement was very satisfactory.

This work presents a methodology for the optimal thermal management of different powertrain devices, with particular regard to ICEs, power electronic units (IGBT) and PEM Fuel cells. The methodology makes use of Model Predictive Control by means of a zero-dimensional model for the heat transfer between the device and the coolant. The control is based on the careful monitoring of the coolant thermal state by means of a metrics for the occurrence of nucleate boiling. The introduction of an electrically driven pump for the control of the coolant flow rate is considered. The effectiveness of the proposed approach is presented with reference to an ICE operation. Experimental tests show the advantages of the methodology during warm-up, under fully warmed operation and for the avoidance of after-boiling.

In this work, a dynamic 0-D electro-thermal model of a lithium-polymer battery for automotive applications is presented. The model predicts the battery temperature during its charging/discharging phases under different environmental and operating conditions, by considering the requested power or current, the coolant flow rate and its temperature as model inputs. The model was first validated with experimental data carried out at the test bench where only the convective heat transfer between the battery and the ambient air was considered. The accuracy of the internal heat generation model was experimentally assessed for different current discharge rates. Then, a liquid cooling system was designed on purpose, assembled, and installed on the battery at the test bench for the improvement of the model predictions in liquid convection conditions.