مکانیزم شکست ناشی از خزش در طی حادثه شدید یک رآکتور‌ آبی‌تحت‌فشار به‌جهت انتقال مواد رادیواکتیو به محیط‌زیست اهمیت ویژه‌ای برخوردار است. دنبال شدید، حرارت واپاشی منتقل‌شده سایر قسمت‌های سیستم‌خنک‌کننده رآکتور می‌تواند منجر گرم‌شدن سازه‌های سیستم خنک‌کننده (RCS) و خرابی نواحی تحت‌فشار آسیب‌پذیر شود. قطع‌کامل‌برق (SBO) بدون اقدامات اپراتور (توالی TMLB) یکی محتمل‌ترین سناریوهایی است که ممکن یکپارچ...

The MELCOR code is a detailed system level computer code capable of performing integrated selfconsistent analyses of severe accident progression in commercial nuclear power plants, supporting level 2 probablilistic risk assessment (PRA) studies. Originally developed as a fast running tool with simplified models for performing probabilistic safety analyses and sensitivity studies, MELCOR now emp...

Accidents postulated to occur involving the chemical interaction of lithium with water and air are analyzed for the blanket test module (BTM) in ITER using two different computer models. The first model is a newly developed thermodynamic equilibrium computer model LINT. The second model uses the MELCOR systems code. The same basic logic used in LINT is incorporated into the MELCOR FDI package, ...

Sandia National Laboratories (SNL) has conducted an uncertainty analysis (UA) on the Fukushima Daiichi unit (1F1) accident progression with the MELCOR code. The model used was developed for a previous accident reconstruction investigation jointly sponsored by the US Department of Energy (DOE) and Nuclear Regulatory Commission (NRC). That study focused on reconstructing the accident progressions...

A lot of effort has been spent to prevent the occurrence SA in nuclear plant and develop Severe Accidents (SA) Management mitigate consequences a SA. Those are mainly related limit release fission product environment. The core vessel is not only source products as Spent Fuel Pool (SFP) hosting fuel removed by is, some NPP, inside containment conditions can also occur. This especially important ...

There is a need for fire modeling tools capable of rapid simulation of fire growth and smoke spread in multiple compartments with complex ventilation. Currently available tools are not capable of simulation of complex ventilation arrangements in a timely manner. To address this problem, a new fire model called Fire and Smoke SIMulator (FSSIM) has been developed. FSSIM is a network model whose c...

Abstract Today, using a best-estimate approach is key factor in the simulation and prediction of thermal-hydraulic other multi-physics phenomena occurring during nuclear severe accidents. The requires quantification both epistemic stochastic uncertainties safety codes to be effective. This assessment approach, named Best Estimate Plus Uncertainty (BEPU), being pursued as an alternative traditio...

During the last 40 years, many studies have been carried out to investigate the different phenomena occurring during a Severe Accident (SA) in a Nuclear Power Plant (NPP). Such efforts have been supported by the execution of different experimental campaigns, and the integral Phébus FP tests were probably some of the most important experiments in this field. In these tests, the degradation of a ...