Abstract Helically coiled once-through steam generators being compact in size and most efficient for heat transfer have been widely used in many SMRs (Small and Medium-size Reactor). It is very imperative to study the hydraulic characteristics of the helically coiled once-through steam generator prior to their integration with SMRs. In this study a thermal hydraulics code that uses a two-fluid two-phase flow model with the consideration of thermal non-equilibrium is developed for thermal-hydraulic characteristics analyses of helically coiled steam generators. A pressure-velocity coupling algorithm is applied to solve equations and a set of heat transfer correlations and frictional pressure drop correlations are embedded into the code. Validation of the code is done using experimental data of pressure drop and heat transfer for helical coil tubes. The code is also tested for simulation of the transient as well as steady state thermal-hydraulic characteristics of OTSG (Once-Through Steam Generator) of IRIS (International Reactor Innovative and Secure) and results are compared with the design data and the RELAP5’s result, the simulation results are found in close agreement with these available results.

中文翻译：

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螺旋盘管直流蒸汽发生器热工水力分析程序的开发

摘要 螺旋盘管直流蒸汽发生器体积小、传热效率最高，已广泛应用于许多SMR（中小型反应堆）。在与 SMR 集成之前研究螺旋盘管直流蒸汽发生器的水力特性是非常必要的。在这项研究中，开发了一个热工水力代码，该程序使用两流体两相流模型并考虑了热非平衡，用于螺旋盘管蒸汽发生器的热工水力特性分析。应用压力-速度耦合算法来求解方程，并将一组传热相关性和摩擦压降相关性嵌入到代码中。使用螺旋盘管的压降和传热实验数据对代码进行验证。