A STUDY OF THERMOMAGNETIC ROTARY ENGINE USING NICKEL AND IRON

• Main Author: MAFTUKH FAJAR (NIM : 90213006), DINAR
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/21775
• Institution: Institut Teknologi Bandung

A thermomagnetic rotary engine/MPT was designed in the form of a wheel made of ferromagnetic wires. One point in the wheel located in magnetic field was heated by a heat source (Q). When the heating had reached Curie temperature, the point would be shifted by other points as consequence of the attractive magnetic force since it had changed into paramagnetic. The shift made the wheel rotated and produced a rotational work (W). The goals of the research were: creating MPT and describing the mechanism, describing the influence of type material and number of wire winding variations on rotational frequency of MPT, and calculating the efficiency. The materials used were nickel and iron with wire diameter (d) of 1 mm and 0,5 mm. The wire was varied into 1 till 3 windings (N). <br /> <br /> MPT yielded 3 efficiency calculations: thermodynamic (Nterm), mechanical (Nterm), and exergetic (Nex) efficiency. Thermodynamic efficiency was also called Carnot efficiency that depends on temperature difference between hot and cold reservoir. Mechanical efficiency was obtained from ratio between rotational work and heat received by system. Exergetic efficiency was obtained from ratio between thermodynamic and mechanical efficiency. MPT with nickel wire had highest rotational frequency than MPT with iron wire. It was because nickel had lower Curie temperature than iron. For nickel, the engine that yielded the highest rotational frequency was MPT with nickel wire 0,5 mm = 3, since it had the most wire windings among the three wires. For iron, the engine that yielded the highest rotational frequency was MPT with iron wire = 0.5 mm =1, since it had the smallest mass among the four wires. From both materials, the number of wire winding and wire mass oppositely influenced the rotational frequency of MPT. MPT with nickel and iron material respectively had in about (1,68-7,21)x10-6 % and (1,42-4,05)x10-8 %. These values were so relatively small that the MPT using nickel and iron were just used limitedly as a model to demonstrate a heat engine that works based on phase transition of magnetic materials.