A non-analog Monte Carlo simulation method for slab albedo problem with linear-anisotropic scattering

Öz

Bu çalışmada, sol taraftan bir anizotropik ve tek hızlı nötron demetine maruz kalan sonsuz çoğaltıcı olmayan bir levha ortamının albedo ve iletim faktörünü simüle etmek için analog olmayan bir Monte Carlo yöntemi geliştirilmiştir. Daha yüksek hassasiyete sahip sonuçlar elde etmek için, simülasyon sırasında zorla çarpışma, örtük yakalama ve Russian-Roulette gibi farklı varyans azaltma teknikleri kullanılmıştır. Nötronların farklı geliş yönleri için, hem izotropik hem de lineer anizotropik saçılımlar durumunda, albedo ve iletim faktörü Monte Carlo'dan tahmin edilip ve H_(N=7) deterministik yönteminden elde edilen sonuçlarla karşılaştırılmıştır. Çoğu durumda Monte Carlo ve H_(N=7) Metotlarının sonuçlarının birbiriyle karşılaştırılabilir olduğu görülmektedir. Bazı durumlarda, deterministik yöntemin albedo ve iletim faktörünü tahmin etmede yetersiz kaldığı, buna karşın Monte Carlo'nun sonuçlarının fiziksel olarak anlamlı olduğu görülmektedir.

Anahtar Kelimeler

• Anizotropik saçılma,
• Nötron transport
• , Monte Carlo,
• Albedo,

A non-analog Monte Carlo simulation method for slab albedo problem with linear-anisotropic scattering

Öz

In this study, a non-analog Monte Carlo method is developed to simulate the albedo and transmission factor of an infinite non-multiplying slab media subjected to a direction-dependent one-speed neutron beam on the left side. In order to obtain more precise results different variance reduction techniques such as forced collision, implicit capture, and Russian-Roulette are taken into consideration. For different incident directions of the neutrons and in the case of both isotropic and linear anisotropic scatterings, the albedo and transmission factor are estimated from the Monte Carlo and compared with the results obtained from the H_(N=7) deterministic method. It is seen that in most cases, the results of both Monte Carlo and H_(N=7) methods are comparable with each other. In some cases, it is also observed that the deterministic method falls short in predicting the albedo and transmission factor, whereas, in contrast, the results of the Monte Carlo are physically meaningful.

Anahtar Kelimeler

• Anisotropic Scattering,
• Neutron transport,
• Monte Carlo,
• Albedo,
• Transmission factor

Kaynakça

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