Graduate Thesis Or Dissertation

 

Pressurized water reactor (PWR) accident analysis using the EMERALD code Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/3n204235t

Descriptions

Attribute NameValues
Creator
Abstract
  • A detail study of a Loss of Coolant Accident (LOCA) in a Pressurized Water Reactor was conducted in order to estimate the consequences of the accident using the computer simulation code EMERALD. An effort was undertaken to modify the EMERALD code and to make it operable on the OSU CYBER computer because this program was too large to run on the present OSU system. This modification was done by breaking EMERALD up into two separate codes, which were called IODINE and NOBLGS, each of which was then small enough to run on the OSU computer. The combination of output results generated by IODINE and NOBLGS gives the same results as EMERALD. For this analysis, two release models, differing in the amount of radioactivity which would be released following a LOCA, were considered. Calculations were performed using the IODINE and NOBLGS programs for both of the release models. In these calculations, three major factors were varied to verify the effect of each on the LOCA. They were the primary containment leak rate, spray removal rate, and the atmospheric dilution factors. A set of calculations was carried out to show the effect of the primary containment leak rate in case of an accident. A significant reduction in off-site doses would result in the situation where the containment does not fail. For example, the total whole body and total thyroid doses, at the plant exclusion boundary, are reduced by a factor of about 290 and 190, respectively, in the case where the primary containment remains intact (normal leak rate) compared to the situation where the containment fails, assuming every other factor is unchanged. Studies were also undertaken to illustrate the dependence of the thyroid exposure on the spray removal rate. Higher doses would result, following a LOCA, for the situation with no spray system operating. For instance, an increase in thyroid dose by a factor of about 16.5 was obtained for the case with no spray as compared to the case when the spray operates at full capacity, assuming the containment remains intact for all periods after the accident. Furthermore, the dependency of the meteorological conditions on the off-site exposures due to a LOCA was studied. As expected, the more unfavorable meteorological conditions give higher dose rates. For example, the total thyroid and total whole body doses for all periods at the plant exclusion boundary increase by a factor of about 360 and 730, respectively, when the most unfavorable meteorological conditions, rather than the actual on-site atmospheric conditions, were used.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome) using Capture Perfect 3.0.82 on a Canon DR-9080C in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items