In order to solve the heat damages in deep mines, a cool-wall cooling technology and its working model are proposed based on the principles of heat absorption and insulation in this paper. During this process, the dif...In order to solve the heat damages in deep mines, a cool-wall cooling technology and its working model are proposed based on the principles of heat absorption and insulation in this paper. During this process, the differential equation of thermal equilibrium for roadway control unit is built, and the heat adsorption control equation of cool-wall cooling system is derived by an integral method, so as to obtain the quantitative relationship among the heat absorption capacity of cooling system, the heat dissipating capacity of surrounding rock and air temperature change. Then, the heat absorption capacity required by air temperature less than the standard value for safety is figured out by section iterative method with the simultaneous solution of heat absorption control equation and the heat dissipation density equation of surrounding rock. Finally, the results show that as the air temperature at the inlet of roadway is 25 ℃, the roadway wall is covered by heat-absorbing plate up to 39% of the area, as well as the cold water is injected into the heat-absorbing plate with a temperature of 20 ℃ and a mass flow of 113.6 kg/s, the air flow temperature rise per kilometer in the roadway can be less than 3 ℃.展开更多
The Mapping Closure Approximation(MCA)approach is developed to describe the statistics of both conserved and reactive scalars in random flows.The statistics include Probability Density Function(PDF),Conditional Dissip...The Mapping Closure Approximation(MCA)approach is developed to describe the statistics of both conserved and reactive scalars in random flows.The statistics include Probability Density Function(PDF),Conditional Dissipation Rate(CDR)and Conditional Laplacian(CL).The statistical quantities are calculated using the MCA and compared with the results of the Direct Nu- merical Simulation(DNS).The results obtained from the MCA are in agreement with those from the DNS.It is shown that the MCA approach can predict the statistics of reactive scalars in random flows.展开更多
The entropy balance equation that describes the entropy budget of atmospheric systems is derived from the Gibbs relation.The distribution of the entropy flows of a west-Pacific typhoon and a Bengal-Bay cyclone is calc...The entropy balance equation that describes the entropy budget of atmospheric systems is derived from the Gibbs relation.The distribution of the entropy flows of a west-Pacific typhoon and a Bengal-Bay cyclone is calculated and thus the dissipativity of the atmospheric systems is revealed.展开更多
In this paper, by using weak dissipative type conditions and weak noncompact conditions, we give the existence of weak solutions of differential equations in weak complete Banach spaces.
基金Project(2018CXNL08) supported by the Fundamental Research Funds for the Central Universities,China。
文摘In order to solve the heat damages in deep mines, a cool-wall cooling technology and its working model are proposed based on the principles of heat absorption and insulation in this paper. During this process, the differential equation of thermal equilibrium for roadway control unit is built, and the heat adsorption control equation of cool-wall cooling system is derived by an integral method, so as to obtain the quantitative relationship among the heat absorption capacity of cooling system, the heat dissipating capacity of surrounding rock and air temperature change. Then, the heat absorption capacity required by air temperature less than the standard value for safety is figured out by section iterative method with the simultaneous solution of heat absorption control equation and the heat dissipation density equation of surrounding rock. Finally, the results show that as the air temperature at the inlet of roadway is 25 ℃, the roadway wall is covered by heat-absorbing plate up to 39% of the area, as well as the cold water is injected into the heat-absorbing plate with a temperature of 20 ℃ and a mass flow of 113.6 kg/s, the air flow temperature rise per kilometer in the roadway can be less than 3 ℃.
基金The project supported by the National Committee of Science and Technology,China,under the Special Funds for Major Basic Research Project (G2000077305 and G1999032801),and the National Natural Science Foundation of China (10325211)
文摘The Mapping Closure Approximation(MCA)approach is developed to describe the statistics of both conserved and reactive scalars in random flows.The statistics include Probability Density Function(PDF),Conditional Dissipation Rate(CDR)and Conditional Laplacian(CL).The statistical quantities are calculated using the MCA and compared with the results of the Direct Nu- merical Simulation(DNS).The results obtained from the MCA are in agreement with those from the DNS.It is shown that the MCA approach can predict the statistics of reactive scalars in random flows.
文摘The entropy balance equation that describes the entropy budget of atmospheric systems is derived from the Gibbs relation.The distribution of the entropy flows of a west-Pacific typhoon and a Bengal-Bay cyclone is calculated and thus the dissipativity of the atmospheric systems is revealed.
基金Project is supportedby the Natural Science Foundation of Shangdong Province.
文摘In this paper, by using weak dissipative type conditions and weak noncompact conditions, we give the existence of weak solutions of differential equations in weak complete Banach spaces.
