| 摘要 |
<p>A waste heat utilization device (2) for an internal combustion engine has a Rankine cycle (8) that recovers waste heat from an internal combustion engine (4), a generator (30) that is rotationally driven by an expander (14) and converts a rotational drive force into electric power, a converter (32) that controls the rotational speed of the expander (14) through the generator (30), refrigerant-condition detecting means (22, 24, 26, 28) that detects the pressure and temperature of a refrigerant passing through the expander (14), and a controller (34) that calculates pressure ratio Rp of the refrigerant in the immediate upstream and downstream of the expander (14) and specific heat ratio K of the refrigerant passing through the expander (14) on the basis of the pressure and temperature of the refrigerant, which have been detected by the refrigerant-condition detecting means (22, 24, 26, 28), calculates a preset pressure ratio Rps of the pressure ratio Rp by multiplying predetermined volume ratio Rv of the expander (14) by the specific heat ratio K, and specifies rotational speed N of the expander (14) to the converter (32) on the basis of the pressure ratio Rp and the preset pressure ratio Rps.</p> |
