A new cooling technique based on thermal driving in high centrifugal field （TDHCF） is developed for gas turbine rotational components, such as turbine blades. The key point of TDHCF is to enhance heat transfer by th...A new cooling technique based on thermal driving in high centrifugal field （TDHCF） is developed for gas turbine rotational components, such as turbine blades. The key point of TDHCF is to enhance heat transfer by the fluid thermal driving in closed loop small channels placed in the high centrifugal field. Heat transfer characteristics of the new cooling technique are analyzed. In experiments, two different fluids （liquid water and Freon R12） are used as thermal driving media （fluid inside the loop channel）. And the channel width d is 1 mm and the height h is 30 mm. The temperature is measured by thermocouples and an average heat transfer coefficient KH is defined to indicate heat transfer capacity of TDHCF. Experimental results show that KH is enhanced when heat flux and the rotating speed increase. And thermal properties of thermal driving media are also influenced by KH. Larger KH can be achieved by using Freon R12 as thermal driving medium compared with using liquid water. It can increase to 2 300 W/（m^2 · K） and it is much higher than that of the normal air cooling method （usually at the level of 600-1200 W/（m^2·K））. All fundamental studies of TDHCF show that there actually exists thermal driving in the closed loop small channel in the centrifugal field to improve heat transfer characteristics.展开更多
Based on the urgency of thermal hazard control in deep coal mines,we studied the status of deep thermal damage and cooling technology both at home and abroad,summarized the causes of deep thermal hazard,analysed and c...Based on the urgency of thermal hazard control in deep coal mines,we studied the status of deep thermal damage and cooling technology both at home and abroad,summarized the causes of deep thermal hazard,analysed and compared the control technologies for deep thermal hazards.The results show that the causes of deep thermal damage can be attributed to three aspects,i.e.,climate,geological and mining factors,of which the geological factors are deemed the major reasons for thermal hazards.As well,we compared a number of cooling technologies of domestic and overseas provenance,such as central air conditioning cooling technology,ice cooling technology and water cooling technology,with one other cooling technology,i.e.,the HEMS cooling technology,which has a large and important effect with its unique＂pure air＂cooling technology,realizes the utilizing of heat resources from underground to the ground.This technology makes use of heat obtained underground;thus the technology can promote low-carbon environmental economic development in coal mines,in order to achieve low- carbon coal production in China.展开更多
文摘A new cooling technique based on thermal driving in high centrifugal field （TDHCF） is developed for gas turbine rotational components, such as turbine blades. The key point of TDHCF is to enhance heat transfer by the fluid thermal driving in closed loop small channels placed in the high centrifugal field. Heat transfer characteristics of the new cooling technique are analyzed. In experiments, two different fluids （liquid water and Freon R12） are used as thermal driving media （fluid inside the loop channel）. And the channel width d is 1 mm and the height h is 30 mm. The temperature is measured by thermocouples and an average heat transfer coefficient KH is defined to indicate heat transfer capacity of TDHCF. Experimental results show that KH is enhanced when heat flux and the rotating speed increase. And thermal properties of thermal driving media are also influenced by KH. Larger KH can be achieved by using Freon R12 as thermal driving medium compared with using liquid water. It can increase to 2 300 W/（m^2 · K） and it is much higher than that of the normal air cooling method （usually at the level of 600-1200 W/（m^2·K））. All fundamental studies of TDHCF show that there actually exists thermal driving in the closed loop small channel in the centrifugal field to improve heat transfer characteristics.
基金Financial support for this project,provided by the New Century Excellent Talent Program of the Ministry of Education(No.NCET- 08-0833)the National Natural Science Foundation of China(No. 41040027)+1 种基金the National Basic Research Program of China(No. 2006CB202200)the Program for Changjiang Scholars and Innovative Research Team in Universities of China(No.IRT0656)
文摘Based on the urgency of thermal hazard control in deep coal mines,we studied the status of deep thermal damage and cooling technology both at home and abroad,summarized the causes of deep thermal hazard,analysed and compared the control technologies for deep thermal hazards.The results show that the causes of deep thermal damage can be attributed to three aspects,i.e.,climate,geological and mining factors,of which the geological factors are deemed the major reasons for thermal hazards.As well,we compared a number of cooling technologies of domestic and overseas provenance,such as central air conditioning cooling technology,ice cooling technology and water cooling technology,with one other cooling technology,i.e.,the HEMS cooling technology,which has a large and important effect with its unique＂pure air＂cooling technology,realizes the utilizing of heat resources from underground to the ground.This technology makes use of heat obtained underground;thus the technology can promote low-carbon environmental economic development in coal mines,in order to achieve low- carbon coal production in China.
