| Summary: | 碩士 === 國立中興大學 === 農業機械工程學系 === 83 === The greenhouse with plastic cover used in Taiwan are still not
well-developed. The structure of the greenhouse has not been
analyzed. Therefore, the structure is either too weak to be
dangous, or too strong to be wasteful. In this study, the
greenhouse with plastic cover was analyzed by using the finite
element method first. The optimum design of the structure
wasndertaken thereafter. In structural analysis aspect, the
finite element model of greenhouse structure has been
established in this study. The finite element analysis
package, MSC/NASTRAN, was used. The structure subjected to
wind force with various velocities was investigated. In optimum
design aspect, this study integrates the optimum design
package, MOST, and the finite element analysis package, MSC/
NASTRAN, by an interface program coded by C language. By using
the discrete design variables optimization module provided by
MOST, this study had obtained new designs of the structure of
greenhouse. Under the loading condition that the wind velocity
is 32.7m/sec, the total weight of the structure is reduced
about 43.37%. Furthermore, under the loading condition that
the wind velocity is 51.0m/sec, the total weight of the
structure is reduced about 12.66%. In addition, all members in
new design of structures hold safety factors to be over 2.
|
|---|
