Thermal performance of a loop heat pipe with two evaporators and two condensers was examined using a lumped network model analysis. Thermosyphon-type vertical loop heat pipe and capillary-pump-type horizontal loop hea...Thermal performance of a loop heat pipe with two evaporators and two condensers was examined using a lumped network model analysis. Thermosyphon-type vertical loop heat pipe and capillary-pump-type horizontal loop heat pipe were calculated by examining the change of heating rate of two evaporators. Calculation results showed that the vapor and liquid flow rates in the loop heat pipe and the thermal conductance of the heat pipe changed significantly depending on the distribution ratio of the heating rate of the multiple evaporators. The thermal performance of the vertical loop heat pipe with two evaporators was also examined and experimental results of flow direction and thermal conductance of the heat pipe agreed with the analytical results. The lumped network model analysis is therefore considered accurate and preferable for the practical design of a loop heat pipe with multiple evaporators.展开更多
High penetration of distributed renewable energy promotes the development of an active distribution network(ADN).The power flow calculation is the basis of ADN analysis.This paper proposes an approximate linear three-...High penetration of distributed renewable energy promotes the development of an active distribution network(ADN).The power flow calculation is the basis of ADN analysis.This paper proposes an approximate linear three-phase power flow model for an ADN with the consideration of the ZIP model of the loads and PV nodes.The proposed method is not limited to radial topology and can handle high R/X ratio branches.Case studies on the IEEE 37-node distribution network show a high accuracy and the proposed method is applicable to practical uses such as linear or convex optimal power flow of the ADN.展开更多
Routing loops can cause packet loss and long delay problems in the traditional network. Even in future networks – Software-Defined Networks, with loop-free implementation mechanism, it still suffers loop problems. In...Routing loops can cause packet loss and long delay problems in the traditional network. Even in future networks – Software-Defined Networks, with loop-free implementation mechanism, it still suffers loop problems. In this paper, we propose an architecture to solve the loop problem in SDN. Unlike the existing passive routing loop detection algorithm, this algorithm processes based on the SDN loop-free characteristic, by auditing third-party network forwarding rules’ modification requests to avoids loop generation, thus avoid the network loop problems. Testbed is built to simulate our proposed algorithm. The evaluation shows that the loop audit algorithm proposed in this paper has better performance in extra spatial utilization and smaller number of extra interactions between SDN controller and switches.展开更多
文摘Thermal performance of a loop heat pipe with two evaporators and two condensers was examined using a lumped network model analysis. Thermosyphon-type vertical loop heat pipe and capillary-pump-type horizontal loop heat pipe were calculated by examining the change of heating rate of two evaporators. Calculation results showed that the vapor and liquid flow rates in the loop heat pipe and the thermal conductance of the heat pipe changed significantly depending on the distribution ratio of the heating rate of the multiple evaporators. The thermal performance of the vertical loop heat pipe with two evaporators was also examined and experimental results of flow direction and thermal conductance of the heat pipe agreed with the analytical results. The lumped network model analysis is therefore considered accurate and preferable for the practical design of a loop heat pipe with multiple evaporators.
基金supported in part by the National Key R&D Program of China(No.2016YFB0900100)the National Science Foundation of China(No.51325702,51677096).
文摘High penetration of distributed renewable energy promotes the development of an active distribution network(ADN).The power flow calculation is the basis of ADN analysis.This paper proposes an approximate linear three-phase power flow model for an ADN with the consideration of the ZIP model of the loads and PV nodes.The proposed method is not limited to radial topology and can handle high R/X ratio branches.Case studies on the IEEE 37-node distribution network show a high accuracy and the proposed method is applicable to practical uses such as linear or convex optimal power flow of the ADN.
基金supported by the project of Ministry of science and technology special emphasis Research and Development Surveying and Mapping Cyberspace Resources (NO. 112044017001)Cernet Next Generation Internet Technology Innovation(No. NGII20170417)China Ministry of Education-CMCC Research Fund (No. MCM20170306)
文摘Routing loops can cause packet loss and long delay problems in the traditional network. Even in future networks – Software-Defined Networks, with loop-free implementation mechanism, it still suffers loop problems. In this paper, we propose an architecture to solve the loop problem in SDN. Unlike the existing passive routing loop detection algorithm, this algorithm processes based on the SDN loop-free characteristic, by auditing third-party network forwarding rules’ modification requests to avoids loop generation, thus avoid the network loop problems. Testbed is built to simulate our proposed algorithm. The evaluation shows that the loop audit algorithm proposed in this paper has better performance in extra spatial utilization and smaller number of extra interactions between SDN controller and switches.