BRAYTON CYCLE DEVICE AND EXHAUST HEAT ENERGY RECOVERY DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

An exhaust heat energy recovery device for an internal combustion engine capable of efficiently recovering exhaust heat energy without increasing the exhaust back pressure of the internal combustion engine and a Brayton cycle device usable for the exhaust heat energy recovery device. The Brayton cycle device (1) comprises a scroll compressor (4) and a scroll expansion machine (6). Accordingly, the structure of the Brayton cycle device (1) can be simplified and formed compact. A working fluid is compressed by the scroll compressor (4) in the state of being divided and sealed by the combination of a fixed scroll with a turning scroll, and expanded by the scroll expansion machine (6). Therefore, the device has an excellent conversion efficiency for converting heat energy to kinetic energy. Also, heat is transferred from exhaust gas to the working fluid through the tube wall of a flow passage (30a) and the expansion machine case (12) of the scroll expansion machine (6) for heat exchange. As a result, the Brayton cycle device (1) can be further reduced in size without affecting the back pressure of an energy source such as the exhaust gas.