A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulati...A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulation structure. How to use the general thermal response factors and z-transfer function coefficients toca1culate the indoor air temperature variation directly is also studied. It is shown through practical use that it iseasy to program with the methods presented in this paper and the calculated results are reliable.展开更多
This work presents a semi-analytical model to explore the effects of cooling rate on the thermal shock resistance behavior of a functionally graded ceramic （FGC） plate with a periodic array of edge cracks. The FGC i...This work presents a semi-analytical model to explore the effects of cooling rate on the thermal shock resistance behavior of a functionally graded ceramic （FGC） plate with a periodic array of edge cracks. The FGC is assumed to be a thermally heterogeneous material with constant elastic modulus and Poisson＇s ratio. The cooling rate applied at the FGC surface is modeled using a linear ramp function. An integral equation method and a closed form asymptotic temperature solution are employed to compute the thermal stress intensity factor （TSIF）. The thermal shock residual strength and critical thermal shock of the FGC plate are obtained using the SIF criterion. Thermal shock simulations for an Al2O/Si3N4 FGC indicate that a finite cooling rate leads to a significantly higher critical thermal shock than that under the sudden cooling condition. The residual strength, however, is relatively insensitive to the cooling rate.展开更多
Thermally activated delayed fluorescence（TADF） emitters are primarily comprised of intramolecular charge-transfer（ICT） molecules with small energy difference between the lowest singlet and triplet excited states.T...Thermally activated delayed fluorescence（TADF） emitters are primarily comprised of intramolecular charge-transfer（ICT） molecules with small energy difference between the lowest singlet and triplet excited states.They lend extremely favorable electroluminescent performance to organic light-emitting diodes（OLEDs）.This paper summarizes relevant issues and research efforts in the theoretical prediction of singlet- and triplet-transition energies of ICT molecules via time-dependent density functional theory（TDDFT）.The successful application of the descriptor-based optimal Hartree-Fock percentage method and the optimally tuned range-separated functional to many TADF systems represent an interesting approach to the exact prediction of the complex excited-state molecular dynamics within TDDFT.展开更多
This paper analyzes the convective heat transfer enhancement mechanism of latent heat functionally thermal fluid. By using the proposed internal heat source model, the influence of each factor affecting the heat trans...This paper analyzes the convective heat transfer enhancement mechanism of latent heat functionally thermal fluid. By using the proposed internal heat source model, the influence of each factor affecting the heat transfer enhancement of laminar flow in a circular tube with constant heat flux is analyzed. The main influencing factors and the mechanisms of heat transfer enhancement are clarified, and the influences of the main factors on the heat transfer enhancement are quantitatively analyzed. A modified Nusselt number for internal flow is introduced to describe more effectively the degree of heat transfer enhancement for latent functionally thermal fluid.展开更多
文摘A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulation structure. How to use the general thermal response factors and z-transfer function coefficients toca1culate the indoor air temperature variation directly is also studied. It is shown through practical use that it iseasy to program with the methods presented in this paper and the calculated results are reliable.
文摘This work presents a semi-analytical model to explore the effects of cooling rate on the thermal shock resistance behavior of a functionally graded ceramic （FGC） plate with a periodic array of edge cracks. The FGC is assumed to be a thermally heterogeneous material with constant elastic modulus and Poisson＇s ratio. The cooling rate applied at the FGC surface is modeled using a linear ramp function. An integral equation method and a closed form asymptotic temperature solution are employed to compute the thermal stress intensity factor （TSIF）. The thermal shock residual strength and critical thermal shock of the FGC plate are obtained using the SIF criterion. Thermal shock simulations for an Al2O/Si3N4 FGC indicate that a finite cooling rate leads to a significantly higher critical thermal shock than that under the sudden cooling condition. The residual strength, however, is relatively insensitive to the cooling rate.
基金the Exploratory Research for Advanced Technology (ERATO) of Japanthe Key Special Program of the Ministry of Science and Technology of China(No.2016YFB0401000) for financial support
文摘Thermally activated delayed fluorescence（TADF） emitters are primarily comprised of intramolecular charge-transfer（ICT） molecules with small energy difference between the lowest singlet and triplet excited states.They lend extremely favorable electroluminescent performance to organic light-emitting diodes（OLEDs）.This paper summarizes relevant issues and research efforts in the theoretical prediction of singlet- and triplet-transition energies of ICT molecules via time-dependent density functional theory（TDDFT）.The successful application of the descriptor-based optimal Hartree-Fock percentage method and the optimally tuned range-separated functional to many TADF systems represent an interesting approach to the exact prediction of the complex excited-state molecular dynamics within TDDFT.
基金supported by the National Natural Science Foundation of China(Grant No.50076020)the Key Projects of Basic Research and Development of China(Grant No.G2000026309)the Excellent Young Faculty Foundation of the Ministry of Education of China.
文摘This paper analyzes the convective heat transfer enhancement mechanism of latent heat functionally thermal fluid. By using the proposed internal heat source model, the influence of each factor affecting the heat transfer enhancement of laminar flow in a circular tube with constant heat flux is analyzed. The main influencing factors and the mechanisms of heat transfer enhancement are clarified, and the influences of the main factors on the heat transfer enhancement are quantitatively analyzed. A modified Nusselt number for internal flow is introduced to describe more effectively the degree of heat transfer enhancement for latent functionally thermal fluid.
