Akademik Veri Yönetim Sistemi
STROJNISKI VESTNIK-JOURNAL OF MECHANICAL ENGINEERING, cilt.68, sa.12, ss.757-770, 2022 (SCI-Expanded)
In this study first a double-cylinder V-type air compressor has been converted to a gamma-type Stirling engine. Some components of the compressor have been used in the converted engine. For this reason, the air compressor has determined some technical features of the Stirling engine. Other parts of the Stirling engine have been manufactured. Then, the optimum operating parameters to provide maximum thermal efficiency have been investigated using the nodal thermodynamic analysis considering that the engine is powered by solar energy. In the analysis, helium as the working fluid is used due to its suitable thermodynamic features and safety usage. The optimum working fluid mass and engine speed have been determined as 0.15 g and 100 rad/s for all hot-end temperatures (750 K, 800 K, and 850 K). Also, the optimum displacer height has been determined as 190 mm since there is no significant improvement in the thermal efficiency after this dimension. The maximum thermal efficiency has been obtained as 46.5 % at 100 rad/s and 850 K. At this point, the indicated power is determined as 657.8 W. If the engine speed increases from 100 rad/s to 300 rad/s, the indicated power becomes 1141.5 W. The experimental results indicate that the maximum output power with helium is 42.5 W at 4 bar charge pressure, 260 rpm engine speed, and 350 degrees C hot-end temperature. The engine output power could be further increased with some modifications such as higher hot-end temperature, reduction of heat losses and gas leakage.