Verification of SARAX code system in the reactor core transient calculation based on the simplifi ed EBRII benchmark

Xiaoqian Jia,Youqi Zheng,Xianna Du,Yongping Wang,Jianda Chen 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.5

This paper shows the verification work of SARAX code system in the reactor core transient calculationbased on the simplified EBR-II Benchmark. The SARAX code system is an analysis package developed byXi'an Jiaotong University and aims at the advanced reactor R&D. In this work, a neutron-photon coupledpower calculation model and a spatial-dependent reactivity feedback model were introduced. To verifythe models used in SARAX, the EBR-II SHRT-45R test was simplified to an ULOF transient with an inputflowrate change curve by fitting from reference. With the neutron-photon coupled power calculationmodel, SARAX gave close results in both power fraction and peak power prediction to the referenceresults. The location of the hottest assembly from SARAX and reference are the same and the relativepower deviation of the hottest assembly is 2.6%. As for transient analysis, compared with experimentalresults and other calculated results, SARAX presents coincident results both in trend and absolute value. The minimum value of core net reactivity during the transient agreed well with the reported results,which ranged from 0.3$ to 0.35$. The results verify the models in SARAX, which are correct and ableto simulate the in-core transient with reliable accuracy.

The applicability study and validation of TULIP code for full energy range spectrum

Chen Wenjie,Du Xianan,Wang Rong,Zheng Youqi,Wang Yongping,Wu Hongchun 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.12

NECP-SARAX is a neutronics analysis code system for advanced reactor developed by Nuclear Engineering Computational Physics Laboratory of Xi’an Jiaotong University. In past few years, improvements have been implemented in TULIP code which is the cross-section generation module of NECP-SARAX, including the treatment of resonance interface, considering the self-shielding effect in non-resonance energy range, hyperfine group method and nuclear library with thermal scattering law. Previous studies show that NECP-SARAX has high performance in both fast and thermal spectrum system analysis. The accuracy of TULIP code in fast and thermal spectrum system analysis is demonstrated preliminarily. However, a systematic verification and validation is still necessary. In order to validate the applicability of TULIP code for full energy range, 147 fast spectrum critical experiment benchmarks and 170 thermal spectrum critical experiment benchmarks were selected from ICSBEP and used for analysis. The keff bias between TULIP code and reference value is less than 300 pcm for all fast spectrum benchmarks. And that bias keeps within 200 pcm for thermal spectrum benchmarks with neutronmoderating materials such as polyethylene, beryllium oxide, etc. The numerical results indicate that TULIP code has good performance for the analysis of fast and thermal spectrum system

Conceptual design of a MW heat pipe reactor

Wu Yunqin,Zheng Youqi,Chen Qichang,Li Jinming,Du Xianan,Wang Yongping,Tao Yushan 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.3

In recent years, unmanned underwater vehicles (UUV) have been vigorously developed, and with the continuous deepening of marine exploration, traditional energy can no longer meet the energy supply. Nuclear energy can achieve a huge and sustainable energy supply. The heat pipe reactor has no flow system and related auxiliary systems, and the supporting mechanical moving parts are greatly reduced, the noise is relatively small, and the system is simpler and more reliable. It is more favorable for the control of unmanned systems. The use of heat pipe reactors in unmanned underwater vehicles can meet the needs for highly compact, long-life, unmanned, highly reliable, ultra-quiet power supplies. In this paper, a heat pipe reactor scheme named UPR-S that can be applied to unmanned underwater vehicles is designed. The reactor core can provide 1 MW of thermal power, and it can operate at full power for 5 years. UPR-S has negative reactive feedback, it has inherent safety. The temperature and stress of the reactor are within the limits of the material, and the core safety can still be guaranteed when the two heat pipes are failed.

A Filament Level Analysis on 3-D Orthogonal Weave Microgeometry Modeling under Different Yarn Tension

Ying Ma,Yueyan Liu,Congying Deng,Xiang Chen,Yang Zhao,Sheng Lu,Youqi Wang 한국섬유공학회 2020 Fibers and polymers Vol.21 No.10

3-D woven textile is generated through the weaving process. Yarn is a non-continuum material domain, thestructure of which is determined by inter fiber movement. In this study, the micro-geometry of 3-D orthogonal weave isgenerated at filament level predicting through the weaving process implementing the digital element approach (DEA). First,the basic concepts and explicit algorithm of DEA is introduced. The method of calculating adjusted digital fiber materialproperty in terms of discretization resolution is proposed. Second, the unit-cell topology of 3-D orthogonal weave is definedby a position matrix. The calculation of potential energy of the cell is derived. At last, a dynamic weaving process is designedto investigate the effect of yarn tension on fabric micro-geometry and cell energy. 4 unit-cells are generated under 4 sets oftension combination. Results show that as the fabric thickness decrease, the filaments of the weft yarns move towards thecenter. The weft yarns at the top and bottom deform into their final shape first. The applied tension on weaver plays adominant role in determining fabric thickness and convergence speed. By comparing the numerical results with themicroscope pictures taken from the actual specimen, it is concluded that the fabric micro-geometry produced by tensioncombination 4 closely matches the experimental results.

Comparison between Craniospinal Irradiation and Limited-Field Radiation in Patients with Non-metastatic Bifocal Germinoma

Bo Li,Wenyi Lv,Chunde Li,Jiongxian Yang,Jiajia Chen,Jin Feng,Li Chen,Zhenyu Ma,Youqi Li,Jiayi Wang,Yanwei Liu,Yanong Li,Shuai Liu,Shiqi Luo,Xiaoguang Qiu 대한암학회 2020 Cancer Research and Treatment Vol.52 No.4

Purpose Whether craniospinal irradiation (CSI) could be replaced by limited-field radiation in non-metastatic bifocal germinoma remains controversial. We addressed the issue based on the data from our series and the literature. Materials and Methods Data from 49 patients diagnosed with non-metastatic bifocal germinoma at our hospital during the last 10 years were collected. The Pediatric Quality of Life Inventory 4.0 was used to evaluate health-related quality of life (HRQOL). Additionally, 81 patients identified from the literature were also analyzed independently. Results In our cohort, 34 patients had tumors in the sellar/suprasellar (S/SS) plus pineal gland (PG) regions and 15 in the S/SS plus basal ganglia/thalamus (BG/T) regions. The median follow-up period was 52 months (range, 10 to 134 months). Our survival analysis showed that patients treated with CSI (n=12) or whole-brain radiotherapy (WBRT; n=34) had comparable disease-free survival (DFS; p=0.540), but better DFS than those treated with focal radiotherapy (FR; n=3, p=0.016). All 81 patients from the literature had tumors in the S/SS+PG regions. Relapses were documented in 4/45 patients treated with FR, 2/17 treated with whole-ventricle irradiation, 0/4 treated with WBRT, and 1/15 treated with CSI. Survival analysis did not reveal DFS differences between the types of radiation field (p=0.785). HRQOL analysis (n=44) in our cohort found that, compared with S/SS+PG germinoma, patients with BG/T involvement had significantly lower scores in social and school domains. However, HRQOL difference between patients treated with CSI and those not treated with CSI was not significant. Conclusion In patients with non-metastatic bifocal germinoma, it is rational that CSI could be replaced by limited-field radiation. HRQOL in patients with BG/T involvement was poorer.