Based on the second law of thermodynamics,a method of energy consumption evaluation of electrohydrodynamics(EHD) enhancement of heat transfer was presented, the profit factor of available energy was newly defined.The ...Based on the second law of thermodynamics,a method of energy consumption evaluation of electrohydrodynamics(EHD) enhancement of heat transfer was presented, the profit factor of available energy was newly defined.The experimental data were analyzed. The results showed that the profit factor of available energy increased with increasing heat flux under the same voltage given in experiments, while decreased with increasing voltage under the same heat flux given in experiments.It was found for the first time that the application of EHD enhancement of heat transfer was not economical when the voltage was higher than a critical value at a low heat flux. This method provided a theoretical basis for the economy of EHD heat transfer enhancement.展开更多
The electrohydrodynamics (EHD) enhancement of convection heat transfer of water in a jacket tube heat exchanger was studied through an experimental method in this paper. In the experiment,a DC high voltage electrode...The electrohydrodynamics (EHD) enhancement of convection heat transfer of water in a jacket tube heat exchanger was studied through an experimental method in this paper. In the experiment,a DC high voltage electrode was set in the central tube-side of the heat exchanger,and the high voltage electrode in the tube-side was adjustable in the range of 0-40 kV. Five differ-ent combinations of heat transfer enhancement experiments were conducted under the different voltage and rate of flow. The results indicate that the maximal enhancement coefficient θ is 1.224 when the flow rate of tube-side inlet is 0.1 m3/h. It is proved that,for the work medium of water,the convective heat transfer can be enhanced by applying high electric field. The performance of EHD-enhanced is sensitive to the variation of flow rate,and in the same flow rate,there exist an optimized voltage in the EHD-enhanced process ra-ther than the monotonic positive-correlation relationship.展开更多
Electrohydrodynamics (EHD) has been applied in many areas, such as EHD enhanced heat transfer, EHD pump, electrospray mass spectrometry, electrospray nano- technology, etc. The basic theories underlying these applicat...Electrohydrodynamics (EHD) has been applied in many areas, such as EHD enhanced heat transfer, EHD pump, electrospray mass spectrometry, electrospray nano- technology, etc. The basic theories underlying these applications and a brief review of the EHD advances are presented in this paper. As electrospray is an important branch of EHD, the applications of electrospray are particularly discussed. Finally, this paper gives some suggestions for the future research and development.展开更多
文摘Based on the second law of thermodynamics,a method of energy consumption evaluation of electrohydrodynamics(EHD) enhancement of heat transfer was presented, the profit factor of available energy was newly defined.The experimental data were analyzed. The results showed that the profit factor of available energy increased with increasing heat flux under the same voltage given in experiments, while decreased with increasing voltage under the same heat flux given in experiments.It was found for the first time that the application of EHD enhancement of heat transfer was not economical when the voltage was higher than a critical value at a low heat flux. This method provided a theoretical basis for the economy of EHD heat transfer enhancement.
基金Supported by the National Natural Science Foundation of China (51006076, 50906065)the Program for Excellent Young and Mid-dle-Aged Researchers in Hubei Province (Q20081508)
文摘The electrohydrodynamics (EHD) enhancement of convection heat transfer of water in a jacket tube heat exchanger was studied through an experimental method in this paper. In the experiment,a DC high voltage electrode was set in the central tube-side of the heat exchanger,and the high voltage electrode in the tube-side was adjustable in the range of 0-40 kV. Five differ-ent combinations of heat transfer enhancement experiments were conducted under the different voltage and rate of flow. The results indicate that the maximal enhancement coefficient θ is 1.224 when the flow rate of tube-side inlet is 0.1 m3/h. It is proved that,for the work medium of water,the convective heat transfer can be enhanced by applying high electric field. The performance of EHD-enhanced is sensitive to the variation of flow rate,and in the same flow rate,there exist an optimized voltage in the EHD-enhanced process ra-ther than the monotonic positive-correlation relationship.
基金This work was supported by the National Natural Science Foundation of China(Grant No.5576022)Chinese Academy of Sciences(Grant No.KJCX-SW-L2)"Sponsor Project on Graduators'Science and Society Practice of Chinese Academy Society".
文摘Electrohydrodynamics (EHD) has been applied in many areas, such as EHD enhanced heat transfer, EHD pump, electrospray mass spectrometry, electrospray nano- technology, etc. The basic theories underlying these applications and a brief review of the EHD advances are presented in this paper. As electrospray is an important branch of EHD, the applications of electrospray are particularly discussed. Finally, this paper gives some suggestions for the future research and development.