ナノ粒子層をウィックとするヒートパイプの伝熱性能に関する研究

抄録

In this research, nanoparticle-layer was used as the wick in a cylindrical heat pipe to experimentally investigate its effect to enhance the heat transfer performance. In the experiment, the one end of the heat pipe was heated using a nichrome wire heater and the other end was cooled using saturated boiling pure water. In addition, effects of pre-coating of the screen mesh and the inside wall of the heat pipe with nanoparticles on heat transfer performance were explored. The experimental results showed that in comparison with the normal heat pipe BBW (bare tube / bare mesh / pure water), the thermal resistances of BNW (bare tube / nanoparticle-coated mesh / pure water) decreased 16-73% if the deposited amount of nanoparticles were sufficient. The critical heat flux (CHF) increased 1.7 times and the performance was not deteriorated even after the CHF condition was experienced. If the weight of deposited nanoparticles was sufficient, the thermal resistances of NXW (nanoparticle-coated tube / no mesh / pure water) decreased 16-71% although CHF dropped about 30%. Performance degraded after the CHF condition was experienced．When the working fluid was changed to a nanofluid, the thermal resistances of NXN (nanoparticle-coated tube / no mesh / nanofluid) decreased 14-74% and the CHF increased 1.6 times. Performance was not deteriorated even after the CHF condition was reached. Since the nanoparticle layer is thin, it may effectively be applied particularly to small heat pipes for small electronic devices.