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Title: CFD model development and data comparison for thermal-hydraulic analysis of HTO pilot scale reactor

Abstract

The DOE Hydrothermal Oxidation (HTO) program is validating computational methods for use in scaling up small HTO systems to production scale. As part of that effort, the computational fluid dynamics code FLUENT is being used to calculate the integrated fluid dynamics and chemical reactions in an HTO vessel reactor designed by MODAR, Inc. Previous validation of the code used data from a benchscale reactor. This reports presents the validation of the code using pilotscale (10 times greater throughput than benchscale) data. The model for the pilotscale reactor has been improved based upon the benchscale data by including better fluid thermal properties, a better solution algorithm, addition of external heat transfer, investigation of the effects of turbulent flow, and, although not built into the computer model, a technique for using the calculated adiabatic oxidation temperatures for selecting initial conditions. Thermal results from this model show very good agreement with the limited test data from MODAR Run 920. In addition to the reactor temperatures, flowfield details, including chemical reaction distribution, and simulated salt particle transport were obtained. This model will be very beneficial in designing and evaluating larger commercial scale units. The results of these calculations indicate that for model validation, moremore » accurate boundary conditions need to be measured in future test runs.« less

Authors:
;
Publication Date:
Research Org.:
EG and G Idaho, Inc., Idaho Falls, ID (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
130634
Report Number(s):
INEL-95/0445
ON: DE96002194; TRN: 96:000098
DOE Contract Number:
AC07-94ID13223
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Sep 1995
Country of Publication:
United States
Language:
English
Subject:
05 NUCLEAR FUELS; WASTES; CHEMICAL REACTION KINETICS; OXIDATION; F CODES; BENCH-SCALE EXPERIMENTS; FLOW MODELS; NUMERICAL DATA; WASTE PROCESSING; THERMAL ANALYSIS; HYDRAULICS

Citation Formats

Kochan, R.J., and Oh, C.H.. CFD model development and data comparison for thermal-hydraulic analysis of HTO pilot scale reactor. United States: N. p., 1995. Web. doi:10.2172/130634.
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Kochan, R.J., & Oh, C.H.. CFD model development and data comparison for thermal-hydraulic analysis of HTO pilot scale reactor. United States. doi:10.2172/130634.
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Kochan, R.J., and Oh, C.H.. Fri . "CFD model development and data comparison for thermal-hydraulic analysis of HTO pilot scale reactor". United States. doi:10.2172/130634. https://www.osti.gov/servlets/purl/130634.
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@article{osti_130634,
title = {CFD model development and data comparison for thermal-hydraulic analysis of HTO pilot scale reactor},
author = {Kochan, R.J. and Oh, C.H.},
abstractNote = {The DOE Hydrothermal Oxidation (HTO) program is validating computational methods for use in scaling up small HTO systems to production scale. As part of that effort, the computational fluid dynamics code FLUENT is being used to calculate the integrated fluid dynamics and chemical reactions in an HTO vessel reactor designed by MODAR, Inc. Previous validation of the code used data from a benchscale reactor. This reports presents the validation of the code using pilotscale (10 times greater throughput than benchscale) data. The model for the pilotscale reactor has been improved based upon the benchscale data by including better fluid thermal properties, a better solution algorithm, addition of external heat transfer, investigation of the effects of turbulent flow, and, although not built into the computer model, a technique for using the calculated adiabatic oxidation temperatures for selecting initial conditions. Thermal results from this model show very good agreement with the limited test data from MODAR Run 920. In addition to the reactor temperatures, flowfield details, including chemical reaction distribution, and simulated salt particle transport were obtained. This model will be very beneficial in designing and evaluating larger commercial scale units. The results of these calculations indicate that for model validation, more accurate boundary conditions need to be measured in future test runs.},
doi = {10.2172/130634},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Sep 01 00:00:00 EDT 1995},
month = {Fri Sep 01 00:00:00 EDT 1995}
}
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Technical Report:
View Technical Report (2.03 MB)
DOI:  10.2172/130634
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