Comprehensive Thermal Management for Future Gasoline Engines

Authors

Dipl.-Ing. M. Brinker, Dipl.-Ing. T. Müller, Dipl.-Ing. M. Reichenbach, Dipl.-Ing. M. Plankenbühler, Adam Opel AG, Rüsselsheim; Dr. A. Zahdeh, Dr. J. Gatowski, GM Global Propulsion Systems, Pontiac, USA

Year

2017

Print Info

Fortschritt-Berichte VDI, Series 12, No 802

Summary

Taking full advantage of thermal management requires a comprehensive approach that includes the design of the engine coolant jacket, the hardware and branches in the cooling circuit, and the control system. We have described a system that:

• Has an engine coolant jacket layout with several key features. The flow is targeted at areas of high heat flux with a general pattern of flow across the engine. This allows for a minimum of pressure drop. Provision is made for split cooling. Flow through the engine block can be controlled independently of flow through the IEM and cylinder head.
• Allows for warming or cooling of the engine and transmission oil depending on the engine and vehicle operating condition. Warming is accomplished with a large contribution from energy recuperated by the IEM. The flexibility for managing heat flow is achieved with the use of a multi-port control valve and an electric pump.
• Has a control strategy that seeks to maximize fuel economy while balancing the need for engine temperature control, customer demands, and engine performance. This is accomplished by continuous monitoring of the engine state and precise control of the electric coolant pump and control valve. Operation of the thermal management system has been broken down into several modes. These modes include engine warmup as well as operation while fully warmed up.

Vehicle-level testing has shown that there are significant benefits to our approach which considers engine operation under all conditions. Looking at results from the WLTP, which includes substantial operation after the engine is warm, indicates that almost half of the fuel economy benefit is achieved after warmup. Order