The experiments of pressure drop and flow distribution in subchannels of a 37-pin wire-wrapped rod bundle have been performed to evaluate the reliability of existing friction factor correlations and provide available experimental data to validate the accuracy of the thermal hydraulic codes for the design of the lead-based reactor. The isokinetic sampling technique was applied to measure the flow rate of each subchannel at the rod bundle outlet. The experiments were carried out within the flow rate range of 0.6 ∼ 5.0 kg/s and the inlet temperature range of 20 ∼ 80℃. The Reynolds number of these experiments covers the range of 1100 ∼ 22000.

The CFD pre-analysis revealed that the number of rods has little effect on the subchannel friction factor. The pressure drop measuring section belongs to the fully developed region. The friction factors and flow split factors measured were compared with the existing friction factor correlations. The prediction results of the Chiu-Rohsenow-Todreas (CRT) model agree well with the experimental results of subchannels. The upgraded detailed Cheng and Todreas (UCTD) model is the best fit wire-wrapped rod bundle friction factor correlation and the maximum error is 15% between Reynolds numbers 1100 and 22000. When it comes to the interior subchannel, the experimental data falls within 50% of the UCRD model between interior subchannel Reynolds numbers 900 and 13000. The updated correlations for predicting bundle transition Reynolds numbers are presented in this paper. The subchannel friction factor and the flow split factor are coupled with each other. The derivation of the subchannel transition points proves that the pressure drop experiment and the flow distribution experiment are self-consistent.

进行了37针绕线棒束子通道中的压降和流量分布的实验，以评估现有摩擦系数相关性的可靠性，并提供可用的实验数据，以验证用于设计的热力液压代码的准确性铅基反应堆。等速采样技术用于测量杆束出口处每个子通道的流速。实验是在0.6〜5.0kg / s的流量范围和入口温度为20〜80℃的范围内进行的。这些实验的雷诺数范围为1100〜22000。

CFD的预分析表明，杆数对子通道摩擦系数影响很小。压降测量部分属于完全发达的区域。将测得的摩擦系数和分流系数与现有的摩擦系数相关性进行比较。Chiu-Rohsenow-Todreas（CRT）模型的预测结果与子通道的实验结果非常吻合。升级后的详细Cheng和Todreas（UCTD）模型是最合适的绕线棒束摩擦系数相关性，雷诺数1100和22000之间的最大误差为15％。关于内部子通道，实验数据落入50内部子通道雷诺数900和13000之间的UCRD模型的百分比。本文介绍了预测束过渡雷诺数的更新相关性。子通道摩擦因数和分流因数相互耦合。子通道过渡点的推导证明了压降实验和流量分布实验是自洽的。