Aniseh Abdalla | Tsinghua University (original) (raw)

Papers by Aniseh Abdalla

Frontiers in Energy Research, Feb 14, 2020

In this paper, we have investigated the influence of air-fountain injection to study the hydrogen... more In this paper, we have investigated the influence of air-fountain injection to study the hydrogen diffusion behavior with the help of 3-Dimensional code, HYDRAGON. Three different turbulence models i. e., Standard k −, model, Re-Normalized Group k − m model and Realizable k − e model have been studied carefully and the comparison of simulated data with experimental data were performed. The effect of air-injection was examined using three different velocities i.e., 0.411, 2.803, and 5.143 m/s to evaluate the phenomena of stratification break-up. When we kept the velocity of the air-injection as low as 0.411 m/s, the simulated results obtained through these three turbulence models were very close to experimental data. As the velocity was set to 5.143 m/s, the simulated data captured the experimental data well. But, when the velocity of air-injection was kept 2.803 m/s, the two turbulence models i.e., SKE and RNG turbulence models gave satisfactory results. However, when we added the turbulent diffusivity coefficient to RNG and RLZ turbulence models in the HYDRAGON code, a minor influence was investigated in these simulation results.

ICONE23-1277 Investigation of the Influence of Turbulence Models on the Simulation of the Gas Distribution

Proceedings of the International Conference on Nuclear Engineering, ICONE, 2015

233U Evaluation Comparison Study

The aim of this study is to investigate the availability and accuracy of the cross section data f... more The aim of this study is to investigate the availability and accuracy of the cross section data for 233U to perform the calculations of the critical system. Two evaluated data libraries are available, U.S. data bank (ENDF) and the Japanese data bank (JENDL), by using BAYES method for resonance parameters available in SAMMY code and weighted least square method with nonlinear regression by using FITWR computer code. Evaluation of the 233U has been investigated by using of SAMMY code, in order to generate a useful data base for critical calculations, the computer code FITWR for experimental - experimental data fitting show same results obtained from Bayes method included within SAMMY code, with a slight deference in the results at the evaluated cross sections due to different mathematical methods have different results.Copyright © 2014 by ASME

SAE technical paper series, Apr 3, 2018

Catalysts Specifications DOC Ф10.5"x6" 400 cpsi/4 mil CDPF Ф10.5"x11" 200 cpsi/12 mil Circumferen... more Catalysts Specifications DOC Ф10.5"x6" 400 cpsi/4 mil CDPF Ф10.5"x11" 200 cpsi/12 mil Circumferential Uniformity Test 24 thermocouples were inserted into the DPF channels to measure the inner temperature of the filter. The temperature circumferential uniformity of three different sections at the DPF length direction was analyzed.

Nuclear Science and Techniques, Sep 8, 2017

This paper presents the gas distribution analysis by injecting air fountain into the containment ... more This paper presents the gas distribution analysis by injecting air fountain into the containment and simulations with the HYDRAGON code. Turbulence models of standard k-e (SKE), re-normalization group k-e (RNG) and a realizable k-e (RLZ) are used to assess the effects on the gas distribution analysis during a severe accident in a nuclear power plant. By comparing with experimental data, the simulation results of the RNG and SKE turbulence models agree well with the experimental data on the prediction of dimensionless density distributions. The results illustrate that the turbulence model choice had a small effect on the simulation results, particularly the region near to the air fountain source.

Frontiers in Energy Research, 2020

In this paper, we have investigated the influence of air-fountain injection to study the hydrogen... more In this paper, we have investigated the influence of air-fountain injection to study the hydrogen diffusion behavior with the help of 3-Dimensional code, HYDRAGON. Three different turbulence models i. e., Standard k −, model, Re-Normalized Group k − m model and Realizable k − e model have been studied carefully and the comparison of simulated data with experimental data were performed. The effect of air-injection was examined using three different velocities i.e., 0.411, 2.803, and 5.143 m/s to evaluate the phenomena of stratification break-up. When we kept the velocity of the air-injection as low as 0.411 m/s, the simulated results obtained through these three turbulence models were very close to experimental data. As the velocity was set to 5.143 m/s, the simulated data captured the experimental data well. But, when the velocity of air-injection was kept 2.803 m/s, the two turbulence models i.e., SKE and RNG turbulence models gave satisfactory results. However, when we added the turbulent diffusivity coefficient to RNG and RLZ turbulence models in the HYDRAGON code, a minor influence was investigated in these simulation results.

Simulation of Catalyzed Diesel Particulate Filter for Active Regeneration Process Using Secondary Fuel Injection

SAE Technical Paper Series, 2017

SAE Technical Paper Series, 2018

Catalysts Specifications DOC Ф10.5"x6" 400 cpsi/4 mil CDPF Ф10.5"x11" 200 cpsi/12 mil Circumferen... more Catalysts Specifications DOC Ф10.5"x6" 400 cpsi/4 mil CDPF Ф10.5"x11" 200 cpsi/12 mil Circumferential Uniformity Test 24 thermocouples were inserted into the DPF channels to measure the inner temperature of the filter. The temperature circumferential uniformity of three different sections at the DPF length direction was analyzed.

ICONE23-1277 Investigation of the Influence of Turbulence Models on the Simulation of the Gas Distribution

The Proceedings of the International Conference on Nuclear Engineering (ICONE), 2015

Journal of Nuclear Science and Technology, 2017

The mitigation of hydrogen in the containment of nuclear reactor after the Loss of Coolant Accide... more The mitigation of hydrogen in the containment of nuclear reactor after the Loss of Coolant Accident is essential to preserve the structural reliability of the containment. This paper presents the results of the systematic work done by using the HYDRAGON code to investigate the effect of turbulence models on the concentration distribution of hydrogen and to determine the HYDRAGON code thermal-hydraulic simulation capability during a severe accident at the nuclear power plant. The HYDRAGON code is developed by the Department of Engineering Physics, Tsinghua University, which is an independent research program. The influence of various types of turbulence models, i.e. a standard k − ε model, a re-normalized group (RNG) k − ε model, and a realizable k − ε model were analyzed and the simulation results were compared with the experimental data. When simulation results were compared to experimental data, it was found that, in most compartments, the standard k − ε model generally yielded reasonable agreement with the experimental results as compared to RNG k − ε and realizable k − ε models; however, for probes P7 and P12, better trend was captured by RNG k − ε and realizable k − ε models, respectively.

Nuclear Science and Techniques, 2017

This paper presents the gas distribution analysis by injecting air fountain into the containment ... more This paper presents the gas distribution analysis by injecting air fountain into the containment and simulations with the HYDRAGON code. Turbulence models of standard k-e (SKE), re-normalization group k-e (RNG) and a realizable k-e (RLZ) are used to assess the effects on the gas distribution analysis during a severe accident in a nuclear power plant. By comparing with experimental data, the simulation results of the RNG and SKE turbulence models agree well with the experimental data on the prediction of dimensionless density distributions. The results illustrate that the turbulence model choice had a small effect on the simulation results, particularly the region near to the air fountain source.

233 U Evaluation Comparison Study

Volume 4: Radiation Protection and Nuclear Technology Applications; Fuel Cycle, Radioactive Waste Management and Decommissioning; Computational Fluid Dynamics (CFD) and Coupled Codes; Reactor Physics and Transport Theory, 2014

The aim of this study is to investigate the availability and accuracy of the cross section data f... more The aim of this study is to investigate the availability and accuracy of the cross section data for 233U to perform the calculations of the critical system. Two evaluated data libraries are available, U.S. data bank (ENDF) and the Japanese data bank (JENDL), by using BAYES method for resonance parameters available in SAMMY code and weighted least square method with nonlinear regression by using FITWR computer code. Evaluation of the 233U has been investigated by using of SAMMY code, in order to generate a useful data base for critical calculations, the computer code FITWR for experimental - experimental data fitting show same results obtained from Bayes method included within SAMMY code, with a slight deference in the results at the evaluated cross sections due to different mathematical methods have different results.Copyright © 2014 by ASME

Nuclear Data Statistical Treatment

Volume 5: Fuel Cycle, Radioactive Waste Management and Decommissioning; Reactor Physics and Transport Theory; Nuclear Education, Public Acceptance and Related Issues; Instrumentation and Controls; Fusion Engineering, 2013

Several methods have been developed in order to evaluate the best fit for nuclear data parameters... more Several methods have been developed in order to evaluate the best fit for nuclear data parameters, these methods relies on sequence logical steps should be followed to get accurate and reliable results, it subdivided into: (1) the physical model have been used (2) data types (3) statistical methods (4) problems. This paper will discuss the statistical methods used to evaluate the best fit for the nuclear data. The difficulty in finding a real and reasonable solution to the fitting of data can be made easier by choosing the right fitting method. Different methods will converge differently depending on several parameters like the correct choose of the fitting function and number of fitting parameters. Here we will discuss the uses of two methods, first is Differential evaluation for nonlinear data to optimize a problem by iterative to improve the solution with regard to the quality. The second one is nonlinear regression method, this method used a model function is not linear in the p...

Pramana, 2013

In an accelerator-driven subcritical system (ADS), a high-performance spallation neutron source i... more In an accelerator-driven subcritical system (ADS), a high-performance spallation neutron source is used to feed the subcritical reactor. Neutron generation depends on the proton beam intensity. If the beam intensity is increased by a given factor, the number of generated neutrons will increase. The mechanism yielding a high rate of neutron production per energy is the spallation process, and this mechanism produces very high-energy deposition in the spallation target material. Producing a high rate of neutrons is accompanied by creation of problems of decay heat cooling and radiological protection. As a first step in designing a full-scale industrial ADS, a small-scale experimental ADS, which is similar to the European experimental ADS (XADS) is analysed. The analysis presented in this paper is based on lead-bismuth eutectic (LBE) cooled XADS-type experimental reactors, designed during the European experimental (PDS-XADS) project. Computational fluid dynamics analysis has been carried out for the spallation target. Steady-state behaviour and shear stress transport turbulence model with the automatic wall treatment were applied in the present analysis.

Application of Some Turbulence Models to Simulate Buoyancy-Driven Flow

Volume 4: Radiation Protection and Nuclear Technology Applications; Fuel Cycle, Radioactive Waste Management and Decommissioning; Computational Fluid Dynamics (CFD) and Coupled Codes; Reactor Physics and Transport Theory, 2014

During severe accident in the nuclear power plant, a considerable amount of hydrogen can be gener... more During severe accident in the nuclear power plant, a considerable amount of hydrogen can be generated by an active reaction of the fuel-cladding with steam within the pressure vessel which may be released into the containment of nuclear power plant. Hydrogen combustion may occur where there is sufficient oxygen, and the hydrogen release rates exceed 10% of the containment. During hydrogen combustion, detonation force and short term pressure may be produced. The production of these gas species can be detrimental to the structural integrity of the safety systems of the reactor and the containment. In 1979, the Three Mile Island (1979) accident occurred. This accident compelled experts and researchers to focus on the study of distribution of hydrogen inside the containment of nuclear power plant. However after the Fukushima Dai-ichi nuclear power plant accident (2011), the modeling of the gas behavior became important topic for scientists. For the stable and normal operation of the containment, it is essential to understand the behavior of hydrogen inside the containment of nuclear power plant in order to mitigate the occurrence of these types of accidents in the future. For this purpose, it is important to identify how burnable hydrogen clouds are produced in the containment of nuclear power plant. The combustion of hydrogen may occur in different modes based on geometrical complexity and gas composition. Reliable turbulence models must be used in order to obtain an accurate estimation of the concentration distribution as a function of time and other physical phenomena of the gas mixture. In this study, a small turbulence model are in reasonable agreement as compared to the benchmark experimental data.

The aim of this study is to investigate the availability and accuracy of the cross section data f... more The aim of this study is to investigate the availability and accuracy of the cross section data for 233 U to perform the calculations of the critical system. Two evaluated data libraries are available, U.S. data bank (ENDF) and the Japanese data bank (JENDL), by using BAYES method for resonance parameters available in SAMMY code and weighted least square method with nonlinear regression by using FITWR computer code. Evaluation of the 233 U has been investigated by using of SAMMY code, in order to generate a useful data base for critical calculations, the computer code FITWR for experimental -experimental data fitting show same results obtained from Bayes method included within SAMMY code, with a slight deference in the results at the evaluated cross sections due to different mathematical methods have different results

Several methods have been developed in order to evaluate the best fit for nuclear data parameters... more Several methods have been developed in order to evaluate the best fit for nuclear data parameters, these methods relies on sequence logical steps should be followed to get accurate and reliable results, it subdivided into: (1) the physical model have been used (2) data types (3) statistical methods (4) problems. This paper will discuss the statistical methods used to evaluate the best fit for the nuclear data.

Diesel oxidation catalyst (DOC) upstream of catalyzed diesel particulate filter (CDPF) with addit... more Diesel oxidation catalyst (DOC) upstream of catalyzed diesel particulate filter (CDPF) with additional diesel injection (hydrocarbon injection, HCI) were used to control the particulate matter (PM) emissions to meet stringent emission regulations for heavy-duty diesel vehicles. This study optimized the location of injector upstream of DOC by evaluating the uniformity of HC distribution on the entrance of DOC. An HCI was used in active regeneration to enhance the exothermic heat of CDPF to initiate the soot regeneration. Numerical analysis was established for the combination of after-treatment technology DOC-CDPF, and a spray model for HCI was implemented into a commercial CFD code named AVL FIRE. Different locations and orientations of the injector were tested. The results show that injector location has a significant effect on the optimal mixing between the exhaust gas and injected hydrocarbon (HC). Optimum injector location is the injector located farthest from DOC, while the long distance between injector and DOC allows enough time for injected HC to form secondary droplets, as it mixes well with exhaust gas downstream. Using HCI upstream of DOC causes the exhaust gas temperature to increase and reaches 550 ℃ at the entrance of CDPF, which is enough to initiate active DPF regeneration.

Advanced exhaust after-treatment technology is required for heavy-duty diesel vehicles to achieve... more Advanced exhaust after-treatment technology is required for heavy-duty diesel vehicles to achieve stringent Euro VI emission standards. Diesel particulate filter (DPF) is the most efficient system that is used to trap the particulate matter (PM), and particulate number (PN) emissions form diesel engines. The after-treatment system used in this study is catalyzed DPF (CDPF) downstream of diesel oxidation catalyst (DOC) with secondary fuel injection. Additional fuel is injected upstream of DOC to enhance exothermal heat which is needed to raise the CDPF temperature during the active regeneration process.

Frontiers in Energy Research, Feb 14, 2020

In this paper, we have investigated the influence of air-fountain injection to study the hydrogen... more In this paper, we have investigated the influence of air-fountain injection to study the hydrogen diffusion behavior with the help of 3-Dimensional code, HYDRAGON. Three different turbulence models i. e., Standard k −, model, Re-Normalized Group k − m model and Realizable k − e model have been studied carefully and the comparison of simulated data with experimental data were performed. The effect of air-injection was examined using three different velocities i.e., 0.411, 2.803, and 5.143 m/s to evaluate the phenomena of stratification break-up. When we kept the velocity of the air-injection as low as 0.411 m/s, the simulated results obtained through these three turbulence models were very close to experimental data. As the velocity was set to 5.143 m/s, the simulated data captured the experimental data well. But, when the velocity of air-injection was kept 2.803 m/s, the two turbulence models i.e., SKE and RNG turbulence models gave satisfactory results. However, when we added the turbulent diffusivity coefficient to RNG and RLZ turbulence models in the HYDRAGON code, a minor influence was investigated in these simulation results.

ICONE23-1277 Investigation of the Influence of Turbulence Models on the Simulation of the Gas Distribution

Proceedings of the International Conference on Nuclear Engineering, ICONE, 2015

233U Evaluation Comparison Study

The aim of this study is to investigate the availability and accuracy of the cross section data f... more The aim of this study is to investigate the availability and accuracy of the cross section data for 233U to perform the calculations of the critical system. Two evaluated data libraries are available, U.S. data bank (ENDF) and the Japanese data bank (JENDL), by using BAYES method for resonance parameters available in SAMMY code and weighted least square method with nonlinear regression by using FITWR computer code. Evaluation of the 233U has been investigated by using of SAMMY code, in order to generate a useful data base for critical calculations, the computer code FITWR for experimental - experimental data fitting show same results obtained from Bayes method included within SAMMY code, with a slight deference in the results at the evaluated cross sections due to different mathematical methods have different results.Copyright © 2014 by ASME

SAE technical paper series, Apr 3, 2018

Catalysts Specifications DOC Ф10.5"x6" 400 cpsi/4 mil CDPF Ф10.5"x11" 200 cpsi/12 mil Circumferen... more Catalysts Specifications DOC Ф10.5"x6" 400 cpsi/4 mil CDPF Ф10.5"x11" 200 cpsi/12 mil Circumferential Uniformity Test 24 thermocouples were inserted into the DPF channels to measure the inner temperature of the filter. The temperature circumferential uniformity of three different sections at the DPF length direction was analyzed.

Nuclear Science and Techniques, Sep 8, 2017

This paper presents the gas distribution analysis by injecting air fountain into the containment ... more This paper presents the gas distribution analysis by injecting air fountain into the containment and simulations with the HYDRAGON code. Turbulence models of standard k-e (SKE), re-normalization group k-e (RNG) and a realizable k-e (RLZ) are used to assess the effects on the gas distribution analysis during a severe accident in a nuclear power plant. By comparing with experimental data, the simulation results of the RNG and SKE turbulence models agree well with the experimental data on the prediction of dimensionless density distributions. The results illustrate that the turbulence model choice had a small effect on the simulation results, particularly the region near to the air fountain source.

Frontiers in Energy Research, 2020

In this paper, we have investigated the influence of air-fountain injection to study the hydrogen... more In this paper, we have investigated the influence of air-fountain injection to study the hydrogen diffusion behavior with the help of 3-Dimensional code, HYDRAGON. Three different turbulence models i. e., Standard k −, model, Re-Normalized Group k − m model and Realizable k − e model have been studied carefully and the comparison of simulated data with experimental data were performed. The effect of air-injection was examined using three different velocities i.e., 0.411, 2.803, and 5.143 m/s to evaluate the phenomena of stratification break-up. When we kept the velocity of the air-injection as low as 0.411 m/s, the simulated results obtained through these three turbulence models were very close to experimental data. As the velocity was set to 5.143 m/s, the simulated data captured the experimental data well. But, when the velocity of air-injection was kept 2.803 m/s, the two turbulence models i.e., SKE and RNG turbulence models gave satisfactory results. However, when we added the turbulent diffusivity coefficient to RNG and RLZ turbulence models in the HYDRAGON code, a minor influence was investigated in these simulation results.

Simulation of Catalyzed Diesel Particulate Filter for Active Regeneration Process Using Secondary Fuel Injection

SAE Technical Paper Series, 2017

SAE Technical Paper Series, 2018

Catalysts Specifications DOC Ф10.5"x6" 400 cpsi/4 mil CDPF Ф10.5"x11" 200 cpsi/12 mil Circumferen... more Catalysts Specifications DOC Ф10.5"x6" 400 cpsi/4 mil CDPF Ф10.5"x11" 200 cpsi/12 mil Circumferential Uniformity Test 24 thermocouples were inserted into the DPF channels to measure the inner temperature of the filter. The temperature circumferential uniformity of three different sections at the DPF length direction was analyzed.

ICONE23-1277 Investigation of the Influence of Turbulence Models on the Simulation of the Gas Distribution

The Proceedings of the International Conference on Nuclear Engineering (ICONE), 2015

Journal of Nuclear Science and Technology, 2017

The mitigation of hydrogen in the containment of nuclear reactor after the Loss of Coolant Accide... more The mitigation of hydrogen in the containment of nuclear reactor after the Loss of Coolant Accident is essential to preserve the structural reliability of the containment. This paper presents the results of the systematic work done by using the HYDRAGON code to investigate the effect of turbulence models on the concentration distribution of hydrogen and to determine the HYDRAGON code thermal-hydraulic simulation capability during a severe accident at the nuclear power plant. The HYDRAGON code is developed by the Department of Engineering Physics, Tsinghua University, which is an independent research program. The influence of various types of turbulence models, i.e. a standard k − ε model, a re-normalized group (RNG) k − ε model, and a realizable k − ε model were analyzed and the simulation results were compared with the experimental data. When simulation results were compared to experimental data, it was found that, in most compartments, the standard k − ε model generally yielded reasonable agreement with the experimental results as compared to RNG k − ε and realizable k − ε models; however, for probes P7 and P12, better trend was captured by RNG k − ε and realizable k − ε models, respectively.

Nuclear Science and Techniques, 2017

This paper presents the gas distribution analysis by injecting air fountain into the containment ... more This paper presents the gas distribution analysis by injecting air fountain into the containment and simulations with the HYDRAGON code. Turbulence models of standard k-e (SKE), re-normalization group k-e (RNG) and a realizable k-e (RLZ) are used to assess the effects on the gas distribution analysis during a severe accident in a nuclear power plant. By comparing with experimental data, the simulation results of the RNG and SKE turbulence models agree well with the experimental data on the prediction of dimensionless density distributions. The results illustrate that the turbulence model choice had a small effect on the simulation results, particularly the region near to the air fountain source.

233 U Evaluation Comparison Study

Volume 4: Radiation Protection and Nuclear Technology Applications; Fuel Cycle, Radioactive Waste Management and Decommissioning; Computational Fluid Dynamics (CFD) and Coupled Codes; Reactor Physics and Transport Theory, 2014

The aim of this study is to investigate the availability and accuracy of the cross section data f... more The aim of this study is to investigate the availability and accuracy of the cross section data for 233U to perform the calculations of the critical system. Two evaluated data libraries are available, U.S. data bank (ENDF) and the Japanese data bank (JENDL), by using BAYES method for resonance parameters available in SAMMY code and weighted least square method with nonlinear regression by using FITWR computer code. Evaluation of the 233U has been investigated by using of SAMMY code, in order to generate a useful data base for critical calculations, the computer code FITWR for experimental - experimental data fitting show same results obtained from Bayes method included within SAMMY code, with a slight deference in the results at the evaluated cross sections due to different mathematical methods have different results.Copyright © 2014 by ASME

Nuclear Data Statistical Treatment

Volume 5: Fuel Cycle, Radioactive Waste Management and Decommissioning; Reactor Physics and Transport Theory; Nuclear Education, Public Acceptance and Related Issues; Instrumentation and Controls; Fusion Engineering, 2013

Several methods have been developed in order to evaluate the best fit for nuclear data parameters... more Several methods have been developed in order to evaluate the best fit for nuclear data parameters, these methods relies on sequence logical steps should be followed to get accurate and reliable results, it subdivided into: (1) the physical model have been used (2) data types (3) statistical methods (4) problems. This paper will discuss the statistical methods used to evaluate the best fit for the nuclear data. The difficulty in finding a real and reasonable solution to the fitting of data can be made easier by choosing the right fitting method. Different methods will converge differently depending on several parameters like the correct choose of the fitting function and number of fitting parameters. Here we will discuss the uses of two methods, first is Differential evaluation for nonlinear data to optimize a problem by iterative to improve the solution with regard to the quality. The second one is nonlinear regression method, this method used a model function is not linear in the p...

Pramana, 2013

In an accelerator-driven subcritical system (ADS), a high-performance spallation neutron source i... more In an accelerator-driven subcritical system (ADS), a high-performance spallation neutron source is used to feed the subcritical reactor. Neutron generation depends on the proton beam intensity. If the beam intensity is increased by a given factor, the number of generated neutrons will increase. The mechanism yielding a high rate of neutron production per energy is the spallation process, and this mechanism produces very high-energy deposition in the spallation target material. Producing a high rate of neutrons is accompanied by creation of problems of decay heat cooling and radiological protection. As a first step in designing a full-scale industrial ADS, a small-scale experimental ADS, which is similar to the European experimental ADS (XADS) is analysed. The analysis presented in this paper is based on lead-bismuth eutectic (LBE) cooled XADS-type experimental reactors, designed during the European experimental (PDS-XADS) project. Computational fluid dynamics analysis has been carried out for the spallation target. Steady-state behaviour and shear stress transport turbulence model with the automatic wall treatment were applied in the present analysis.

Application of Some Turbulence Models to Simulate Buoyancy-Driven Flow

Volume 4: Radiation Protection and Nuclear Technology Applications; Fuel Cycle, Radioactive Waste Management and Decommissioning; Computational Fluid Dynamics (CFD) and Coupled Codes; Reactor Physics and Transport Theory, 2014

During severe accident in the nuclear power plant, a considerable amount of hydrogen can be gener... more During severe accident in the nuclear power plant, a considerable amount of hydrogen can be generated by an active reaction of the fuel-cladding with steam within the pressure vessel which may be released into the containment of nuclear power plant. Hydrogen combustion may occur where there is sufficient oxygen, and the hydrogen release rates exceed 10% of the containment. During hydrogen combustion, detonation force and short term pressure may be produced. The production of these gas species can be detrimental to the structural integrity of the safety systems of the reactor and the containment. In 1979, the Three Mile Island (1979) accident occurred. This accident compelled experts and researchers to focus on the study of distribution of hydrogen inside the containment of nuclear power plant. However after the Fukushima Dai-ichi nuclear power plant accident (2011), the modeling of the gas behavior became important topic for scientists. For the stable and normal operation of the containment, it is essential to understand the behavior of hydrogen inside the containment of nuclear power plant in order to mitigate the occurrence of these types of accidents in the future. For this purpose, it is important to identify how burnable hydrogen clouds are produced in the containment of nuclear power plant. The combustion of hydrogen may occur in different modes based on geometrical complexity and gas composition. Reliable turbulence models must be used in order to obtain an accurate estimation of the concentration distribution as a function of time and other physical phenomena of the gas mixture. In this study, a small turbulence model are in reasonable agreement as compared to the benchmark experimental data.

The aim of this study is to investigate the availability and accuracy of the cross section data f... more The aim of this study is to investigate the availability and accuracy of the cross section data for 233 U to perform the calculations of the critical system. Two evaluated data libraries are available, U.S. data bank (ENDF) and the Japanese data bank (JENDL), by using BAYES method for resonance parameters available in SAMMY code and weighted least square method with nonlinear regression by using FITWR computer code. Evaluation of the 233 U has been investigated by using of SAMMY code, in order to generate a useful data base for critical calculations, the computer code FITWR for experimental -experimental data fitting show same results obtained from Bayes method included within SAMMY code, with a slight deference in the results at the evaluated cross sections due to different mathematical methods have different results

Several methods have been developed in order to evaluate the best fit for nuclear data parameters... more Several methods have been developed in order to evaluate the best fit for nuclear data parameters, these methods relies on sequence logical steps should be followed to get accurate and reliable results, it subdivided into: (1) the physical model have been used (2) data types (3) statistical methods (4) problems. This paper will discuss the statistical methods used to evaluate the best fit for the nuclear data.

Diesel oxidation catalyst (DOC) upstream of catalyzed diesel particulate filter (CDPF) with addit... more Diesel oxidation catalyst (DOC) upstream of catalyzed diesel particulate filter (CDPF) with additional diesel injection (hydrocarbon injection, HCI) were used to control the particulate matter (PM) emissions to meet stringent emission regulations for heavy-duty diesel vehicles. This study optimized the location of injector upstream of DOC by evaluating the uniformity of HC distribution on the entrance of DOC. An HCI was used in active regeneration to enhance the exothermic heat of CDPF to initiate the soot regeneration. Numerical analysis was established for the combination of after-treatment technology DOC-CDPF, and a spray model for HCI was implemented into a commercial CFD code named AVL FIRE. Different locations and orientations of the injector were tested. The results show that injector location has a significant effect on the optimal mixing between the exhaust gas and injected hydrocarbon (HC). Optimum injector location is the injector located farthest from DOC, while the long distance between injector and DOC allows enough time for injected HC to form secondary droplets, as it mixes well with exhaust gas downstream. Using HCI upstream of DOC causes the exhaust gas temperature to increase and reaches 550 ℃ at the entrance of CDPF, which is enough to initiate active DPF regeneration.

Advanced exhaust after-treatment technology is required for heavy-duty diesel vehicles to achieve... more Advanced exhaust after-treatment technology is required for heavy-duty diesel vehicles to achieve stringent Euro VI emission standards. Diesel particulate filter (DPF) is the most efficient system that is used to trap the particulate matter (PM), and particulate number (PN) emissions form diesel engines. The after-treatment system used in this study is catalyzed DPF (CDPF) downstream of diesel oxidation catalyst (DOC) with secondary fuel injection. Additional fuel is injected upstream of DOC to enhance exothermal heat which is needed to raise the CDPF temperature during the active regeneration process.