Three Dimensional Numerical Simulation of Thermal-Hydraulic Behaviors of CSNS Decoupled Poisoned Hydrogen Moderator With Non-Uniform Heat Source

The Chinese Spallation Neutron Source (CSNS) is the national major scientific equipment, which will be completed around 2018. The moderator is the core of the CSNS parts, and CSNS uses three types of moderator to meet the requirements of different neutron wavelength and pulse shapes, and the structure and flow field of Decoupled Poisoned Hydrogen Moderator (DPHM) is the most complicated. Currently, Computational Fluid Dynamics (CFD) is the primary tool for thermal design of DPHM to ensure the reliability of calculation result and precision of the engineering requirements. In the current work, three-dimensional simulation of fluid-solid conjugate heat transfer and flow for container pipe, poisoned plate and moderator material were carried out, by compiling corresponding UDF program for ANSYS FLUENT to describe the non-uniform heat source distribution accurately. Thermal-Hydraulic behaviors such as pressure disturbance, pressure rise and temperature distribution cooling capacity are investigated.

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Finite Element Method Based Three-Dimensional Thermal Tomography for Disease Diagnosis of Human Body

Journal of Heat Transfer ◽

10.1115/1.4033612 ◽

2016 ◽

Vol 138 (10) ◽

Cited By ~ 2

Author(s):

Chao Jin ◽

Zhi-Zhu He ◽

Jing Liu

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Heat Source ◽

Three Dimensional ◽

Disease Diagnosis ◽

Bioheat Transfer ◽

Source Distribution ◽

Reconstruction Process ◽

Heat Source Distribution ◽

Element Method

A finite element method (FEM)-based thermal approach to reconstruct the disease-associated heat source distribution has been developed. The congruent relationship between the heat sources and the observed temperature is established from the FEM solution matrix. The regularization method based parameter iteration algorithm is further developed to solve the inverse bioheat transfer problems. Typical simulations on sphere model and real digital human head have been performed to validate the feasibility and efficacy of the current method. In addition, the regularization parameter is optimized to speed up the reconstruction process and reduce the thermal noises. All the results indicate that both the heat source distribution and three-dimensional (3D) temperature field within the biological body were successfully reconstructed with acceptable accuracy.

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A Regulated-Current Network Analog for Reactor Fuel End-Cap Temperatures

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-1973-0028 ◽

1973 ◽

Vol 2 (4) ◽

pp. 185-193

Author(s):

J. T. Rogers ◽

R. S. Flemons ◽

G. M. Barns

Keyword(s):

Heat Source ◽

Nuclear Reactor ◽

Complex Geometry ◽

Reactor Fuel ◽

Thermal Design ◽

Source Distribution ◽

Nodal Points ◽

End Caps ◽

Heat Source Distribution ◽

Fuel Elements

An analog of resistors and regulated-current sources has facilitated the thermal design of end caps for nuclear reactor fuel elements. The analog permits cylindrical-symmetric representation of the end caps, adjacent fuel, and sheath. With the analog, temperature distributions in various complex geometry end-cap designs can be readily determined. Non-uniform radial and axial heat source distributions, external uniform or non-uniform heat transfer coefficient distributions, and arbitrary internal contact conductance distributions between components can be treated. A feature of the analog design is the regulation of currents to the nodal points within the simulated fuel region, insuring independence of the current loadings at other nodal points. This facilitates rapid setting of the required heat source distribution. The analog has been used in the design of end caps of fuel elements for different fuel designs. Screening of proposed designs has been accomplished, and design configurations optimized. The principles of the design can be applied to analogs used for many other purposes.

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Assessing Heavy Industrial Heat Source Distribution in China Using Real-Time VIIRS Active Fire/Hotspot Data

Sustainability ◽

10.3390/su10124419 ◽

2018 ◽

Vol 10 (12) ◽

pp. 4419 ◽

Cited By ~ 2

Author(s):

Caihong Ma ◽

Jin Yang ◽

Fu Chen ◽

Yan Ma ◽

Jianbo Liu ◽

...

Keyword(s):

Economic Development ◽

Heat Source ◽

Infrared Imaging ◽

Mainland China ◽

Processing System ◽

Source Distribution ◽

Heavy Industry ◽

Rapid Urbanization ◽

Active Fire ◽

Heat Source Distribution

Rapid urbanization and economic development have led to the development of heavy industry and structural re-equalization in mainland China. This has resulted in scattered and disorderly layouts becoming prominent in the region. Furthermore, economic development has exacerbated pressures on regional resources and the environment and has threatened sustainable and coordinated development in the region. The NASA Land Science Investigator Processing System (Land-SIPS) Visible Infrared Imaging Radiometer (VIIRS) 375-m active fire product (VNP14IMG) was selected from the Fire Information for Resource Management System (FIRMS) to study the spatiotemporal patterns of heavy industry development. Furthermore, we employed an improved adaptive K-means algorithm to realize the spatial segmentation of long-order VNP14IMG and constructed heat source objects. Lastly, we used a threshold recognition model to identify heavy industry objects from normal heat source objects. Results suggest that the method is an accurate and effective way to monitor heat sources generated from heavy industry. Moreover, some conclusions about heavy industrial heat source distribution in mainland China at different scales were obtained. Those can be beneficial for policy-makers and heavy industry regulation.

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