Simulation of One-Dimensional Nuclear-Pumped Laser Generation System Based on Modelica Language

Nuclear-pumped lasers (NPL) utilize nuclear energy pumping to generate laser light and represent a viable approach to directly converting nuclear energy into useful products (coherent photons). Most nuclear-pumped lasers use thermal neutrons provided by pulsed nuclear reactors to initiate nuclear reactions. Nuclear-pumped lasers that use nuclear reactors as thermal neutron sources are also known as reactor-pumped lasers (RPL). Gas lasers mainly use inert gas as the laser medium, which has the characteristics of high output energy and long service life. This paper mainly establishes a one-dimensional He-Xe laser system, which can excite a laser with a wavelength of 2.03 μm, and the efficiency can reach 1% to 4%. According to the different physical processes of the laser generation system, we divided the system into three main components: nuclear reaction component, pump reaction component, and laser generation component. Based on the modeling method of Modelica for physical process componentization, it is used to simulate and verify each component, and the relevant parameters of the component are determined through theoretical calculation and numerical simulation. The componentized modeling method increases the universality and ease of editing of the model, and facilitates the maintenance and later expansion of the model. When the neutron fluence rate is 6.0 × 10¹⁴ cm⁻²·s⁻¹, the laser with a wavelength of 2.03 μm and a power of 38.55 W can be output.