ホウシャセン タンドク リョウホウ ガ ソウコウ シタ Merkel サイボウガン ノ 1レイ

A ９１-year-old man was diagnosed with Merkel cell carcinoma after removal of a mass about １ cm in diameter from the right upper eyelid on August ５, ２０１X. Curative surgery was recommended, but the patient declined. Lymph node metastases to the right lateral angle of the eye and in front of the right ear, and cancer pain in the stump recurrence manifested. Accordingly, irradiation of the right upper eyelid was started from October ３ at ２．５Gy/fraction, and the right lateral corneal lymph nodes were included from October １１, ending at ３５ Gy in １４ fractions. From November ２２，irradiation of the lymph node metastasisin front of the right ear was started, ending at ３２. ５ Gy in １３ fractions. During irradiation, cancer pain was alleviated with opioids. Stump recurrence and lymph node metastases were decreased in size, and Computed Tomography indiated complete response. Radiation monotherapy of Merkel cell carcinoma appears to offer a treatment that should be proactively applied when curative surgery proves difficult or not desired by the patient. Use of opioids during radiotherapy may improve quality of life and enhance the therapeutic effect

Numerical Study on an Interface Compression Method for the Volume of Fluid Approach

Many thermohydraulic issues about the safety of light water reactors are related to complicated two-phase flow phenomena. In these phenomena, computational fluid dynamics (CFD) analysis using the volume of fluid (VOF) method causes numerical diffusion generated by the first-order upwind scheme used in the convection term of the volume fraction equation. Thus, in this study, we focused on an interface compression (IC) method for such a VOF approach; this technique prevents numerical diffusion issues and maintains boundedness and conservation with negative diffusion. First, on a sufficiently high mesh resolution and without the IC method, the validation process was considered by comparing the amplitude growth of the interfacial wave between a two-dimensional gas sheet and a quiescent liquid using the linear theory. The disturbance growth rates were consistent with the linear theory, and the validation process was considered appropriate. Then, this validation process confirmed the effects of the IC method on numerical diffusion, and we derived the optimum value of the IC coefficient, which is the parameter that controls the numerical diffusion

Estimation of Flow Field in Natural Convection with Density Stratification by Local Ensemble Transform Kalman Filter

For estimating thermal flow in a nuclear reactor during an accident accurately, it is important to improve the accuracy of computational fluid dynamics simulations. The temperature and flow velocity are not homogeneous and have large variations in a reactor containment vessel because of its very large volume. In addition, Kelm’s work pointed out that the influence of variations of initial and boundary conditions was important. Therefore, it is necessary to set the initial and boundary conditions taking into account the variations of these physical quantities. However, it is a difficult subject to set such complicated initial and boundary conditions. Then, we can obtain realistic initial and boundary conditions and an accurate flow field by data assimilation, and we can improve the accuracy of the simulation result. In this study, we applied data assimilation by a local ensemble transform Kalman filter to a simulation of natural convection behavior in density stratification, and we performed a twin model experiment. We succeeded in estimating the flow fields and improving the simulation accuracy by the data assimilation, even if we applied the boundary condition with error for the true condition

Overview and main outcomes of the pool scrubbing lumped-parameter code benchmark on hydrodynamic aspects in ipresca project

International audienceAfter the Fukushima Daiichi accident of March 2011, one of the main concerns of the nuclear industry has been the research works for improving atmospheric radioactive release mitigation systems. Pool scrubbing is an important process in reactors that mitigates radioactive release. It is based on the injection of gases containing fission products through a water pool. Bubble hydrodynamics, as a result of gas injection and the associated water pool thermal-hydraulics, is an important aspect of the process since the bubble size, shape, velocity, etc. influence the fission product trapping at the bubble interface with the water. Computer codes dedicated to the pool scrubbing have been mainly developed in the 90’s last century and modelling drawbacks have been identified in particular for bubble hydrodynamics. One of IPRESCA project objectives is to improve the pool scrubbing modelling. In order to highlight the main modelling issues, a benchmark exercise has been performed focusing on the bubble hydrodynamics. This benchmark, performed by nine organisations coming from six countries, aims at simulating a basic configuration, a single upward injector in ambient conditions, experimentally characterized in the RSE tests carried out in the European PASSAM project. In this paper, a short description of the code modelling and a comparison between the code results and the experimental data are presented and discussed. Then, outcomes from the benchmark result analysis and proposals of improvements are emphasized

Overview and main outcomes of the pool scrubbing lumped-parameter code benchmark on hydrodynamic aspects in ipresca project

International audienceAfter the Fukushima Daiichi accident of March 2011, one of the main concerns of the nuclear industry has been the research works for improving atmospheric radioactive release mitigation systems. Pool scrubbing is an important process in reactors that mitigates radioactive release. It is based on the injection of gases containing fission products through a water pool. Bubble hydrodynamics, as a result of gas injection and the associated water pool thermal-hydraulics, is an important aspect of the process since the bubble size, shape, velocity, etc. influence the fission product trapping at the bubble interface with the water. Computer codes dedicated to the pool scrubbing have been mainly developed in the 90’s last century and modelling drawbacks have been identified in particular for bubble hydrodynamics. One of IPRESCA project objectives is to improve the pool scrubbing modelling. In order to highlight the main modelling issues, a benchmark exercise has been performed focusing on the bubble hydrodynamics. This benchmark, performed by nine organisations coming from six countries, aims at simulating a basic configuration, a single upward injector in ambient conditions, experimentally characterized in the RSE tests carried out in the European PASSAM project. In this paper, a short description of the code modelling and a comparison between the code results and the experimental data are presented and discussed. Then, outcomes from the benchmark result analysis and proposals of improvements are emphasized