First calculation of the antenna heating for HFS reflectometry system Yu.S. Shpanskiy, N.N. Vasiliev RRC KURCHATOV INSTITUTE April 10, 2006

Object of the Analyses In the reactor conditions nuclear heating of the waveguides and antenna for HFS reflectometry will take place. Three ways of these components cooling could be designed: - water cooling; - thermal contact with blanket modules; - radiation cooling. First two ways seems problematic. So it is necessary to carry out thermal and mechanical analyses of waveguides and antenna for HFS reflectometry system in order to understand whether its radiation cooling is possible in these conditions.

View of the waveguides and antenna

Blanket cross-section

Antenna Horn

Emissivities of some elements From handbook «Refractory elements and alloys» (in Russian) R.B. Kotelnikov, S.N. Bashlykov, Z.G. Galiakbarov, A.I. Kashtanov Emissivity Temperature, o C

Heat Generation Rate in Antenna D.V. Markovskiy «Calculation of the waveguide nuclear heating in the gap between blanket modules of the ITER» Heat generation rate, W/cm 3 Distance from the first wall, cm

Heat Generation Rate in Antenna Figure Nuclear Heating Rate in the Shield Block From 2004 DDD 1.6 Blanket, Section

One Dimensional estimations a b  q – heat flux from the antenna surface, W/m 2 Tokr – ambient temperature, K oCoC

One Dimensional calculations Temperature vs emissivity Temperature, o C Emissivity

2-D Model

2-D Model. Results of Thermal analysis Emissivity = 1

2-D Model. Results of Thermal analysis Emissivity = 0.5

2-D Model. Results of Thermal analysis Emissivity = 0.2

3-D Model of the Antenna Horn

3-D Mesh of the Antenna Horn Model

Results of thermal analysis. Molybdenum Horn. Results of thermal analysis. Molybdenum Horn. Emissivity = 1

Results of thermal analysis. SS Horn. Results of thermal analysis. SS Horn. Emissivity = 1

Results of thermal analysis. Molybdenum Horn. Results of thermal analysis. Molybdenum Horn. Emissivity = 0.5

Results of thermal analysis. SS Horn. Results of thermal analysis. SS Horn. Emissivity = 0.5

Results of thermal analysis. Molybdenum Horn. Results of thermal analysis. Molybdenum Horn. Emissivity = 0.2

Results of thermal analysis. SS Horn. Results of thermal analysis. SS Horn. Emissivity = 0.2

Results of thermal analysis. Molybdenum Horn. Results of thermal analysis. Molybdenum Horn. Emissivity = 0.1

Results of thermal analysis. SS Horn. Results of thermal analysis. SS Horn. Emissivity = 0.1

Results of mechanical analysis. Molybdenum Horn. Equivalent (von Mises) Stress. Results of mechanical analysis. Molybdenum Horn. Equivalent (von Mises) Stress. Emissivity = 0.1

Results of mechanical analysis. Molybdenum Horn. Displacement. Results of mechanical analysis. Molybdenum Horn. Displacement. Emissivity = 0.1

Conclusions First analyses of the antenna heating for HFS reflectometry system were carried out.First analyses of the antenna heating for HFS reflectometry system were carried out. Maximum temperatures in 3-D calculations are the following: - Mo structure, emissivity = 0.1 => T = 715 o C; - SS structure, emissivity = 0.1 => T = 782 o C.Maximum temperatures in 3-D calculations are the following: - Mo structure, emissivity = 0.1 => T = 715 o C; - SS structure, emissivity = 0.1 => T = 782 o C. Investigations on the possibility of the Emissivity value increase in the reactor conditions are needed.Investigations on the possibility of the Emissivity value increase in the reactor conditions are needed.

Possible ways of Emissivity increase 1. Coating. 2. Making of artificial roughness. F – roughness factor;  rough F S.C. Agababov, V.S. Agababov The influence of geometrical relief of solid body surface at its radiation proprrties. 1-st Russian national conference on heat transfer. Moscow PP  smooth = 0.1