Abstract
The amount of cars equipped with starter generators is expected to rise sharply in the coming years. Therefore, the concerns raised by engine standstill during stop&start operation are growing. Among them, the maintaining of passengers thermal comfort calls for innovations within the climate control field.
Several types of solutions can be explored. They must be distinguished according to the kind of energy storage they use : fuel, electricity or thermal.
This paper first provides theoretical comparison leading to favour certain solutions. For wide applications, thermal storage appears to be the best.
This preferred solution can be divided in several concept as a function of complexity.
A first level is obtained from a simple storage device, which increases the system thermal inertia. When the compressor is off, the air is cooled by this device until it is discharged.
The most sophisticated level integrates a partial secondary loop to produce cold water. The thermal energy is stored in a specific component. An additional heat exchanger cools the air when the compressor is not running.
Several intermediate thermodynamic architectures can be imagined between these two extreme solutions. Some of them are outlined in the paper.
The main part of the paper is dedicated to experimental results showing comparisons between these different thermal storage concepts. For example, the required quantity of storage material is stated as a function of performance
(cooling power and operation time).