A study on the number density in a dual beam LDV

Dual Beam LDV 의 數密度 에 관한 硏究

A study on the number density in a dual beam LDV is carried out with moving particles of various irregular arrangements. Ratious of the particle diameter to the particle to the fringe Spacing are D/.delta. = 0.3, 0.5, 1.0 and 1.5. In the case of the small number of moving particles(N<10), the visibility is influenced much by the difference of the phase of particles for one side fringe and the change in visibility is shown remarkable. In the case of the larger number of particles, the decreasing rate for visibility on the graph is smooth because the effect of the phase difference of particles is decreased by more unitorm distribution of particles over fringes. And the formula of the number density on the basis of probability is fairly compared with experimental values.

본 논문에서는 유동산란입자들을 1개에서 35개까지 불규칙 상태로 배열한 13 가지의 모델을 만들어 probe volume 속으로 횡단시키므로 나타나는 신호를 분석하여 수밀도와 가시도에 대한 실험적 관계를 파악하고 이를 이론식과 비교검토하고자 했다. 또한 두 입자의 간격을 좁혀가면서 실험하므로 간섭무늬에 대한 두 입자의 입상차가 합성신호특성에 중요 파라미터임을 확인했다.