论文标题
气化反应堆技术在太空推进方面的挑战和Janus太空反应堆概念的发展
The challenges of gas-cooled reactor technology for space propulsion and the development of the JANUS space reactor concept
论文作者
论文摘要
为空间应用开发高功率输出核裂变反应堆（大约1 MWE），例如高付费任务和火星以外的长期任务，有很大的动力，在此降低的太阳能中，太阳能使用替代能源来挑战。许多用于空间应用的气冷反应堆设计可在100 kWe制度中提供输出，典型的功率密度约为4 mw/m $ $^3 $。在这里，我们提出了一种使用HE -XE冷却剂并在直接的Brayton周期运行的气冷反应堆设计（称为Janus），可以实现高功率输出（约为0.8 MWE）和比以前发表的设计更高的功率密度（24 MW/m $^3 $）。该核心在石墨基质中采用涂层颗粒燃料形式，并具有较高的堆积分数（45％）。 从CEA发布的Opus空间反应堆设计开始，考虑了各种方法来实现气冷反应堆中的高功率密度，包括改变核心纵横比。我们的Janus设计使用了降低的冷却液通道直径和燃料元件螺距，同时增加了燃料元素的数量并采用了径向富集分区。该设计实现了功率密度的显着提高，同时遵守2000年有效的全功率日的核心生活极限，并达到了1900 K的峰值燃料工作温度。核心已与Eranos和Serpent代码建模，并具有简单但强大的热尺寸工具，并通过我们开发的简单而强大的热尺寸工具来研究峰值燃油温度，以确保其在燃油范围内的限制和燃油限制范围内的限制并有助于最佳限制。
There is a strong motivation to develop high-power output nuclear fission reactors (around 1 MWe) for space applications, such as high-payload missions and long-duration missions beyond Mars, where the reduced solar flux makes using alternative energy sources challenging. Many published gas-cooled reactor designs for space applications deliver outputs in the 100 kWe regime, with typical power densities of around 4 MW/m$^3$. Here we present a gas-cooled reactor design - referred to as JANUS - employing He-Xe coolant and operating on a direct Brayton cycle, that can achieve a high power output (around 0.8 MWe) and higher power density (24 MW/m$^3$) than previously published designs. The core employs a coated particle fuel form with uranium nitride kernels in a graphite matrix and with a high packing fraction (45%). Starting from the CEA's published OPUS space reactor design, a variety of approaches were considered for achieving high power densities in a gas-cooled reactor, including changing the core aspect ratio. Our JANUS design uses a decreased coolant channel diameter and fuel element pitch, whilst increasing the number of fuel elements and employing radial enrichment zoning. The design achieves a significant increase in power density whilst obeying core-life limits of 2000 Effective Full Power Days and a peak fuel operating temperature of 1900 K. The core has been modelled neutronically with the ERANOS and SERPENT codes, with a simple yet robust thermal dimensioning tool developed by us to study peak fuel temperatures, to ensure the fuel operates within its design limitations and to aid optimisation.
