Internal Coupling Between Neutronics and Thermal-Hydraulics With RMC/CTF and Validation Using VERA Benchmarks

Author(s):  
Kaiwen Li ◽  
Shichang Liu ◽  
Juanjuan Guo ◽  
Kan Wang

The main purpose of this work is to realize the internal coupling mode between the Monte Carlo neutronics transport code RMC and sub-channel thermal-hydraulic (TH) code CTF. The coupling was implemented with the coupling interfaces of RMC and CTF. And it features to use memory rather than files to transfer data from each other, which has a lot of advantages. With the internal coupling mode, power distribution calculated from RMC can be precisely provided to CTF, instead of utilizing the approximate method adopted by the external coupling mode. In addition, using memory to transfer data between those two codes can reduce the total calculation time significantly. The percentage of time reduction can be as large as 10%. Moreover, we have realized the parallel execution of CTF in the internal coupling mode and this saves a lot of time during the TH calculation. A modified Virtual Environment for Reactor Application (VERA) Problem #6 assembly and a 4-assembly structure have been used to test the accuracy and efficiency of internal calculation mode to external calculation mode. The results show that internal coupling can give a very close solution to the external one but with 10% time reduce, and can come to an ideal convergence state with only a few iterations.

Author(s):  
Jun Chen ◽  
Liangzhi Cao ◽  
Zhouyu Liu ◽  
Hongchun Wu ◽  
Yijun Zhang

PWR core phenomena can be simulated and predicted more precisely and in more details with high-fidelity neutronics and thermal-hydraulics coupling calculations. An internal coupling between a newly developed high-fidelity neutronics code NECP-X and the sub-channel code SUBSC has been realized. In order to verify the NECP-X/SUBSC coupling system, another high-fidelity neutronics and thermal-hydraulics coupling system OpenMC/SUBSC was developed through external coupling method. Both coupling systems were applied to a simplified PWR 3×3 pin cluster case. The numerical result shows good agreement in both eigenvalue and normalized axial power distribution for a selected pin, demonstrating the success of the internal coupling of NECP-X and SUBSC.


2019 ◽  
Vol 10 (1) ◽  
pp. 78
Author(s):  
Jianjun Hu ◽  
Meixia Jia ◽  
Feng Xiao ◽  
Chunyun Fu ◽  
Lingling Zheng

In order to effectively extend the mileage of pure electric vehicles, the influence of the electromechanical energy conversion principle and the dynamic control of a permanent magnet synchronous motor (PMSM) on the performance of pure electric vehicles are studied with a dual-motor drive system as a carrier in this paper. A vector control strategy based on the speed-torque-current map of a motor is proposed, considering the bus voltage fluctuation influenced by battery charge and discharge. By constructing a complete vehicle model including the dynamic control model of the motor, the power distribution control strategy of a dual-motor coupling mode considering the dynamic characteristics of the motor is developed and simulated on the MATLAB platform. The results show that the dynamic model of the motor is closer to the actual running conditions. The proposed control strategy effectively reduces the demand power, decreases the energy consumption of the electric drive system, and extends the mileage of the vehicle.


Author(s):  
L.H. Bolz ◽  
D.H. Reneker

The attack, on the surface of a polymer, by the atomic, molecular and ionic species that are created in a low pressure electrical discharge in a gas is interesting because: 1) significant interior morphological features may be revealed, 2) dielectric breakdown of polymeric insulation on high voltage power distribution lines involves the attack on the polymer of such species created in a corona discharge, 3) adhesive bonds formed between polymer surfaces subjected to such SDecies are much stronger than bonds between untreated surfaces, 4) the chemical modification of the surface creates a reactive surface to which a thin layer of another polymer may be bonded by glow discharge polymerization.


Author(s):  
H. O. Colijn

Many labs today wish to transfer data between their EDS systems and their existing PCs and minicomputers. Our lab has implemented SpectraPlot, a low- cost PC-based system to allow offline examination and plotting of spectra. We adopted this system in order to make more efficient use of our microscopes and EDS consoles, to provide hardcopy output for an older EDS system, and to allow students to access their data after leaving the university.As shown in Fig. 1, we have three EDS systems (one of which is located in another building) which can store data on 8 inch RT-11 floppy disks. We transfer data from these systems to a DEC MINC computer using “SneakerNet”, which consists of putting on a pair of sneakers and running down the hall. We then use the Hermit file transfer program to download the data files with error checking from the MINC to the PC.


Author(s):  
Tatsuhiko Sato ◽  
Koji Niita ◽  
Norihiro Matsuda ◽  
Shintaro Hashimoto ◽  
Yosuke Iwamoto ◽  
...  

2020 ◽  
pp. 28-33
Author(s):  
A. Yu. Dunaev ◽  
A. S. Baturin ◽  
V. N. Krutikov ◽  
S. P. Morozova

An improved monochromatic radiant source with spectral bandwidth of 4 nm based on supercontinuum laser and a double monochromator was included in absolute cryogenic radiometer-based facility to improve the accuracy of spectral responsivity measurement in the range 0.9–1.6 μm. The developed feedback system ensures stabilization of monochromatic radiant power with standard deviation up to 0.025 %. Radiant power that proceeds detector under test or absolute cryogenic radiometer varies from 0.1 to 1.5 mW in dependence of wavelength. The spectral power distribution of its monochromatic source for various operating mode is presented.


2019 ◽  
Vol 2 (3) ◽  
pp. 141-151
Author(s):  
O. E. Gnezdova ◽  
E. S. Chugunkova

Introduction: greenhouses need microclimate control systems to grow agricultural crops. The method of carbon dioxide injection, which is currently used by agricultural companies, causes particular problems. Co-generation power plants may boost the greenhouse efficiency, as they are capable of producing electric energy, heat and cold, as well as carbon dioxide designated for greenhouse plants.Methods: the co-authors provide their estimates of the future gas/electricity rates growth in the short term; they have made a breakdown of the costs of greenhouse products, and they have also compiled the diagrams describing electricity consumption in case of traditional and non-traditional patterns of power supply; they also provide a power distribution pattern typical for greenhouse businesses, as well as the structure and the principle of operation of a co-generation unit used by a greenhouse facility.Results and discussion: the co-authors highlight the strengths of co-generation units used by greenhouse facilities. They have also identified the biological features of carbon dioxide generation and consumption, and they have listed the consequences of using carbon dioxide to enrich vegetable crops.Conclusion: the co-authors have formulated the expediency of using co-generation power plants as part of power generation facilities that serve greenhouses.


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