一米红外太阳望远镜近场视宁度的研究

项目名称： 一米红外太阳望远镜近场视宁度的研究

项目编号： No.11203076

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 黄善杰

作者单位： 中国科学院云南天文台

项目金额： 24万元

中文摘要： 地基式太阳望远镜及周边设施在观测时会被太阳辐射加热，进而在其周边空气中形成明显的大气湍流。望远镜受镜筒附近光路中的空气湍流影响而产生的像质衰减程度我们称之为近场视宁度，近场视宁度的存在使望远镜的观测能力大打折扣。 强烈的太阳辐射下，一米红外太阳望远镜建筑物的水泥表面会被加热到40摄氏度以上，望远镜封窗也会出现较大的温度起伏和空间梯度。实测及仿真研究显示，风速较小时，封窗和建筑表面发热在镜筒附近引起的空气湍流会严重影响望远镜的成像质量。一米红外太阳望远镜运行中也发现，在风速较小等天气情况下，观测图像会出现不同程度的整体性像质衰减，关闭圆顶并对望远镜通风冷却一段时间后，像质会有改善。 本项目旨在改善一米红外太阳望远镜的近场视宁度，使望远镜在风速较小时也有优良的高分辨成像质量。此问题的解决对提高望远镜的使用效率，延长高分辨观测时间，尤其对太阳活动区进行长时间连续的高分辨观测，具有重要的现实意义。

中文关键词： 视宁度；封窗；地基式太阳望远镜；流固耦合；有限元仿真

英文摘要： As the telescope working，Earth-based Solar telescope and its accessories will be warmed by solar radiation and that would produce atmospheric turbulence around the telescope.The descriptive Parameter to the degradation of the astronomical image quality affected by turbulence of near the telescope tube is defined as near-field seeing and it will negatively affect the image quality. Cement surface of Solar telescope building will be warmed to 40 degrees Celsius above under strong solar radiation. The sealing windows of telescope also have a large range of temperature fluctuation and temperature gradient.Through measurements and simulation, Our studies suggest that the atmospheric turbulence near the telescope tube, caused by hot surfaces of Solar telescope building and sealing windows, have a serious impact on the image quality. As the wind weakening，the astronomical image observed from the 1m infrared solar telescope will have degradation of image quality after working some time，and it can be promoted by closing dome and wind-cooling the telescope. This study aims to improve the near-field seeing and it can fully take advantage of high quality seeing of the Fuxian Lake Observatory. so that even if the wind is weak,the telescope would still observe high-resolution images,and this would be full of practical si

英文关键词： Seeing；Sealing glass；Earth-based Solar Telescope；Fluid-structure Interaction；Finite Element Simulation