Project/Area Number |
06650249
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Thermal engineering
|
Research Institution | OKAYAMA UNIVERSITY |
Principal Investigator |
INABA Hideo OKAYAMA UNIV., MECH.ENGNG., PROFESSOR, 工学部, 教授 (40133805)
|
Co-Investigator(Kenkyū-buntansha) |
OZAKI Koichi OKAYAMA UNIV., MECH.ENGNG., INSTRUCTOR, 工学部, 助手 (20224206)
|
Project Period (FY) |
1994 – 1995
|
Project Status |
Completed (Fiscal Year 1995)
|
Budget Amount *help |
¥2,400,000 (Direct Cost: ¥2,400,000)
Fiscal Year 1995: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1994: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
Keywords | Frost Layr / Melting / Infrared Rays / Ice Crystal / Absorptance / Melted Water / Frost Formation / Defrost |
Research Abstract |
It cannot be avoided the frosting problem for the heat exchanger whose temperature is below 0゚C.In general, some frost melting methods have been used such as the hot gas defrost in the reverse refrigerating cycle. However these methods have many problems. For cxample, it has the economical disadvantage owing to the small ratio of only 20 % of the energy consumed to melt the frost layr to total energy supplied during the defrosting, and it requires longer time to restart the cooling operation. The present research is useful to establish the new energy-saving defrosting method by using of the radiant heat energy. The optimum radiative wavelength range is the infared one for the radiative absorption of the frost layr. The reflector and the bulb of the halogen heater increase the radiant heat intensity of the long wavelength range because it is coated with the alumina ceramics infrared ray radiation. It solves the radiative heat source problem. This radiative heat source makes the frost layr possible to absorb a great part of the radiant heat, as the result, the heat-loss of heating the heat exchanger decreases extremely. Accordingly the defrosting method proposed in the present research is epoch-making one for the refrigeration system requiring defrosting operation. Furthermore, the radiative heat source is also used for defrost by means of the frost sublimation. The present rescarch is to investigate the effect of the radiative wavelength range, radiant heat intensity on defrost process. Moreover, it is also investigated that the radiative heat source of the defrost by means of the frost sublimation. The defrost method proposed in this research makes the defrost operation efficiently and systematize this kind of the defrost method.
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