All the thermohydraulic systems experience entropy generation due to which the performance is found to be degrading. Similarly, due to the flow of coolant such as LN2 (77 K) in the High Temperature Superconducting (HTS) cables, cause the entropy generation. This is due to the friction in the corrugated former through which the coolant flows and due to the finite heat transfer between the coolant and other solid components of the HTS cables. Existence of entropy generation in such thermohydraulic system results in higher pumping power and decrease in heat transfer cause disruption to the state of superconductivity. Hence, in the present work, a detailed investigation on the losses due to entropy generation is done and its effect on the degradation in the performance of HTS cables is presented. As there are no experimental methods to measure the entropy generation, computational method using a commercial code is adapted in estimating the degradation in terms of destruction in exergy. The computational domain is modeled, meshed and analyzed using commercial software ANSYS®. The analysis is carried out with time averaged Reynolds averaged Navier-Stokes (RANS) equations which are solved using Finite Volume Method (FVM) of discretization with $\kappa -\epsilon$ turbulent scheme. As the thermophysical properties of LN₂ are sensitive to the operating temperature (77 K and pressure of 2.7 bar), temperature dependent properties are considered. Further, the flow rates ranging from 11 to 20 L/min and the heat loads ranging from 1 to 3 W/m are considered to estimate the entropy generation rate and exergy destruction. The results obtained from the computational investigation are validated with the experimental results that are available in the literature. From the analysis, it is observed that higher the heat loads higher will be the entropy generation and hence higher exergy destruction. The minimum exergy destruction is possible at the minimum entropy generation rate for different flow rates and heat loads.

所有的热液系统都会产生熵，因此发现性能下降。同样，由于高温超导 (HTS) 电缆中 LN2 (77 K) 等冷却剂的流动，会导致熵的产生。这是由于冷却剂流经的波纹管中的摩擦，以及冷却剂与 HTS 电缆的其他固体组件之间的有限热传递。在这种热液系统中存在熵产生会导致更高的泵送功率和传热减少，从而破坏超导状态。因此，在目前的工作中，对熵产生造成的损耗进行了详细调查，并介绍了它对 HTS 电缆性能下降的影响。由于没有测量熵生成的实验方法，使用商业代码的计算方法适用于估计火用破坏方面的退化。使用商业软件 ANSYS® 对计算域进行建模、网格划分和分析。使用时间平均雷诺平均纳维-斯托克斯 (RANS) 方程进行分析，这些方程使用离散化的有限体积法 (FVM) 求解$\kappa -\epsilon$动荡的计划。由于 LN ₂的热物理特性对工作温度（77 K 和 2.7 bar 的压力）敏感，因此考虑了与温度相关的特性。此外，考虑从 11 到 20 L/min 的流速和从 1 到 3 W/m 的热负荷来估计熵产生率和火用破坏。从计算研究中获得的结果与文献中可用的实验结果进行了验证。从分析中可以看出，热负荷越高，熵的产生越高，火用破坏越高。对于不同的流量和热负荷，在最小熵产生率下，最小的火用破坏是可能的。