Startup model of high temperature heat pipe applied to heat pipe reactor

[Background]: The heat pipe reactor has the characteristics of small size, simple system, no pump or valve or active equipment, and high inherent reliability. It is one of the preferred reactors used in deep sea, deep space and other fields. [Purpose]: This study aims to solve the problem of heat pipe simulation method in the process of heat pipe reactor system analysis. In the systematic analysis of the reactor, the point reactor model is often used to deal with the reactor neutron dynamics problem. Similarly, a heat pipe model is also needed to deal with the heat transfer problem of the heat pipe during the systematic analysis of the heat pipe reactor. [Methods]: In this paper, a new heat pipe model is proposed. Compared with the traditional thermal resistance network model and flat-front method, this model not only has clear and concise physical meaning, but also can simulate the steady / quasi-steady state of the heat pipe, and can also simulate the startup process of the heat pipe. By dividing more fine grids and combining the calculation methods of thermal resistance network model and flat-front method, a new model is finally obtained. This model can also be used to deal with the problem of equivalent multiple heat pipes with a single heat pipe. [Results]: Using this model, a smooth and continuous time-temperature curve is obtained without a step curve. By comparing with the simulation results or experimental results in the literature, it is found that the maximum temperature difference is less than 15%, and the maximum temperature difference is at the heat pipe evaporator wall. [Conclusions]: This model can simulate the heat pipe in different states, with accurate calculation results and less computational burden.