1989 Fiscal Year Final Research Report Summary
Condensation Process of Gaseous Molecules on Thermal and Chemical Active Surfaces
Project/Area Number |
63460103
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Research Category |
Grant-in-Aid for General Scientific Research (B)
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Allocation Type | Single-year Grants |
Research Field |
Thermal engineering
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Research Institution | Tokai University |
Principal Investigator |
SANO Taeko Tokai University, Facul. of Eng. Professor, 工学部, 教授 (60013728)
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Co-Investigator(Kenkyū-buntansha) |
TAKAMOTO Keiji Tokai University, Facul. of Eng. Professor, 工学部, 教授 (90056276)
|
Project Period (FY) |
1988 – 1989
|
Keywords | Gaseous condensation / Molecular dynamics / Numerical simulation / Heterogeneous condensation / Cluster distribution / Vacuum chamber |
Research Abstract |
The condensation process of gaseous molecules of argon on their condensate is studied numerically by using the molecular dynamics method with the Lennard-Jones (6-12) potential. Further, the heterogeneous condensation process by metallic (Ti, Zr, Fe, Co, Cu and Ag) and nonmetallic (C and Si) vapors on solid surfaces is also studied experimentally in vacuum chamber to investigate the effect of their cluster distribution on the condensation process. (1) Any evidence of significant interfacial surface structure is not shown in the results, but inside the condensate ordered structures are observed. (2) The warmer molecules coming into the condensate concentrate more densely near the interface than the cooler molecules accumulating around the interface. (3) The energy flows of condensation and evaporation have a peak just inside the interface of phase change. (4) The concentration of cluster in metallic vapors are fairly high, that is, their number density is not less than that of monomer. (5) The thickness of films made by metallic vapors increases proportionally to time, which means condensation rate is nearly constant, while the thickness of nonmetallic films does not increase linearly. (6) The condensate rate of iron (Fe) increases with the decrease in chamber pressure.
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