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In view of the power quality problems such as voltage fluctuation and transformer overload caused by large-scale access of electric heating equipment, the comprehensive evaluation index system and the evaluation method of the distribution network carrying capacity were proposed. Taking IEEE33 node system as an example, based on the tested node electricity load and thermal load demand, through the calculation of each evaluation index, influence of different electric heating modes on the distribution network carrying capacity was analysed and the rationality of the proposed evaluation method was verified. The results showed that using electric heat pump with thermal storage system for heating can reduce the peak voltage deviation, the network loss and further ensure the safe operation of power distribution network under the premise of satisfying the user’s thermal load demand and the stability of the distribution network.

Supercritical carbon dioxide (SCO2) is widely used in many fields of energy and power engineering, such as nuclear reactors, solar thermal power generation systems, and refrigeration systems. In practical applications, SCO2 undergoes a cooling process significantly when it is cooled near the pseudo−critical point. Because of the drastic variations in thermo−physical properties, the heat transfer characteristics fluctuate, affecting the heat exchange and overall cycle performance. This paper summarizes extensive experiments and numerical simulations on the cooling process of SCO2 in various application scenarios. The effects of various working conditions, such as mass flow, working pressure, pipe diameter, flow direction, and channel shapes, are reviewed. The applicability and computational results using different numerical methods under different working conditions are also summarized. Furthermore, empirical correlations obtained in experiments at different conditions are included. The present review can provide a helpful guideline for the design of effective cooling systems or condensers so that the accuracy of the design and efficiency of the system can be improved.

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