Perpustakaan Digital ITB

Cryogenics is the application of low-temperature fluids (e.g., liquid nitrogen) for useful freezing and preservation, but wastes cold energy. Thermoelectric Generator (TEG), a device that converts temperature difference into electricity through the Seebeck effect, can recover the waste cold energy. In this research, a waste cold recovery system from exhausted cryogenic nitrogen that utilized the TEG was created through an experimental and simulation setup to test the feasibility of recovering waste cold energy. The waste cold recovery system was simulated to explore its temperature field and velocity field. A finite element analysis software was used to apply governing equations to determine the condition of the fluid flow. Furthermore, a turbulence model was considered and predicted using the ????-epsilon model. Temperature and open-circuit voltage from simulation were compared with results from experiment. It was found that temperature and open-circuit voltage of simulation have a maximum value difference of 41.42 K (15.25%) and 6.56 V (51.735 %), respectively from their associated experimental data; with the maximum simulation open-circuit voltage of 19.24 V. Afterwards, the design was modified to give an open-circuit voltage of 14.78 V at highest mass flowrate of cold nitrogen at 4.68 g/s. The modified design produces lower voltage in total, and the power generated by the new prototypes needs to be considered and studied further. Furthermore, although the waste cold recovery system experimental setup should consider the average temperature of TEG surface for more accurate measurement, the study has shown that the waste cold recovery system could be used for useful cryogenic application.