Utilizing the results that the Faddeev model is equivalent to the mesonic sector of the SU（2） Skyrme model, where the baryon number current vanishes everywhere, some exact solutions including the vortex solutions of...Utilizing the results that the Faddeev model is equivalent to the mesonic sector of the SU（2） Skyrme model, where the baryon number current vanishes everywhere, some exact solutions including the vortex solutions of the Faddeev model axe discussed. The solutions are classified by the 2, the new multisoliton solutions are obtained and the pipe shape found. first Chern number. When the Chern number equals distribution of the energy density of the solutions are展开更多
Particulate matter(PM)from high-temperature emissions like chemical plants,coal stoves and vehicle exhausts poses a gravel challenge to human health.To address this issue,researchers have explored vari-ous fiber filte...Particulate matter(PM)from high-temperature emissions like chemical plants,coal stoves and vehicle exhausts poses a gravel challenge to human health.To address this issue,researchers have explored vari-ous fiber filters,yet the bulk struggle to withstand high temperatures.In this study,mullite fiber sponges were developed utilizing low-cost materials and Kármán vortex solution blow spinning,using surfac-tants to improve the spinnability of the sol.Optimized sponges demonstrate ultralight(19 mg cm^(-3)),temperature-resistant reversible compressibility(50% strain)and a water contact angle of 135°.These sponges exhibited exceptional thermal insulation(thermal conductivity:0.0256 W m^(-1) K^(-1))and per-formed well in high-temperature air filtration.At 800℃,the mullite sponge with a base weight of 35 mg cm^(-2),achieved an average filtration efficiency of 98.18%and 99.57% for PM_(2.5) and PM_(2.5-10),respectively,with a quality value of 0.98 Pa^(-1) at a wind speed of 4 cm s^(-1).This low-cost mullite fiber sponge offers a promising avenue for designing high-performance filtration materials.展开更多
The three-component Gross–Pitaevskii equation with an angular momentum rotational term can be served as a model to study spinor Bose–Einstein condensates (BECs) with time–space modulated interactions. Vortex soluti...The three-component Gross–Pitaevskii equation with an angular momentum rotational term can be served as a model to study spinor Bose–Einstein condensates (BECs) with time–space modulated interactions. Vortex solutions of the spinor BECs with spatiotemporally modulated interactions are worked out by similarity transformation. Theoretical analysis and numerical simulation of vortex states are demonstrated. Stable vortex states are obtained by adjusting the frequency of the external potential and the spatiotemporally modulated interaction.展开更多
The time accuracy of the exponentially accurate Fourier time spectral method（TSM） is examined and compared with a conventional 2nd-order backward difference formula（BDF） method for periodic unsteady flows. In part...The time accuracy of the exponentially accurate Fourier time spectral method（TSM） is examined and compared with a conventional 2nd-order backward difference formula（BDF） method for periodic unsteady flows. In particular, detailed error analysis based on numerical computations is performed on the accuracy of resolving the local pressure coefficient and global integrated force coefficients for smooth subsonic and non-smooth transonic flows with moving shock waves on a pitching airfoil. For smooth subsonic flows, the Fourier TSM method offers a significant accuracy advantage over the BDF method for the prediction of both the local pressure coefficient and integrated force coefficients. For transonic flows where the motion of the discontinuous shock wave contributes significant higherorder harmonic contents to the local pressure fluctuations,a sufficient number of modes must be included before the Fourier TSM provides an advantage over the BDF method.The Fourier TSM, however, still offers better accuracy than the BDF method for integrated force coefficients even for transonic flows. A problem of non-symmetric solutions for symmetric periodic flows due to the use of odd numbers of intervals is uncovered and analyzed. A frequency-searching method is proposed for problems where the frequency is not known a priori. The method is tested on the vortex shedding problem of the flow over a circular cylinder.展开更多
In this paper,we construct stationary classical solutions of the shallow water equation with vanishing Froude number Fr in the so-called lake model.To this end we need to study solutions to the following semilinear el...In this paper,we construct stationary classical solutions of the shallow water equation with vanishing Froude number Fr in the so-called lake model.To this end we need to study solutions to the following semilinear elliptic problem -ε^2div(△u/b)=b(u-qlog1/ε)^p+,in Ω,u=0,on aΩfor small ε>0,where p>1,div(△q/b)=0 and ΩcR^2 is a smooth bounded domain.We show that if q^2/b has m strictly local minimum(maximum)points Zi,i=1,...,m,then there is a stationary classical solution approximating stationary m points vortex solution of shallow water equations with vorticity m∑i=1π2q(zi)/b(zi).Moreover,strictly local minimum points of q^2/b on the boundary can also give vortex solutions for the shallow water equation.展开更多
基金National Natural Science Foundation of China under Grant No.10601031the Natural Science Foundation of Shanghai Municipal Education Commission under Grant No.05LZ08the Foundation of Shanghai University of Electric Power under Grant No.K2005-01
文摘Utilizing the results that the Faddeev model is equivalent to the mesonic sector of the SU（2） Skyrme model, where the baryon number current vanishes everywhere, some exact solutions including the vortex solutions of the Faddeev model axe discussed. The solutions are classified by the 2, the new multisoliton solutions are obtained and the pipe shape found. first Chern number. When the Chern number equals distribution of the energy density of the solutions are
基金sponsored by the National Key R&D Program of China(No.2020YFC1910000)the National Natural Science Foundation of China(Grants No 51978153).
文摘Particulate matter(PM)from high-temperature emissions like chemical plants,coal stoves and vehicle exhausts poses a gravel challenge to human health.To address this issue,researchers have explored vari-ous fiber filters,yet the bulk struggle to withstand high temperatures.In this study,mullite fiber sponges were developed utilizing low-cost materials and Kármán vortex solution blow spinning,using surfac-tants to improve the spinnability of the sol.Optimized sponges demonstrate ultralight(19 mg cm^(-3)),temperature-resistant reversible compressibility(50% strain)and a water contact angle of 135°.These sponges exhibited exceptional thermal insulation(thermal conductivity:0.0256 W m^(-1) K^(-1))and per-formed well in high-temperature air filtration.At 800℃,the mullite sponge with a base weight of 35 mg cm^(-2),achieved an average filtration efficiency of 98.18%and 99.57% for PM_(2.5) and PM_(2.5-10),respectively,with a quality value of 0.98 Pa^(-1) at a wind speed of 4 cm s^(-1).This low-cost mullite fiber sponge offers a promising avenue for designing high-performance filtration materials.
基金Project supported by the Beijing Natural Science Foundation, China (Grand No. 1182009)the National Natural Science Foundation of China (Grant No. 11471182).
文摘The three-component Gross–Pitaevskii equation with an angular momentum rotational term can be served as a model to study spinor Bose–Einstein condensates (BECs) with time–space modulated interactions. Vortex solutions of the spinor BECs with spatiotemporally modulated interactions are worked out by similarity transformation. Theoretical analysis and numerical simulation of vortex states are demonstrated. Stable vortex states are obtained by adjusting the frequency of the external potential and the spatiotemporally modulated interaction.
基金supported by the State Scholarship Fund of the China Scholarship Council (Grant 2009629129)
文摘The time accuracy of the exponentially accurate Fourier time spectral method（TSM） is examined and compared with a conventional 2nd-order backward difference formula（BDF） method for periodic unsteady flows. In particular, detailed error analysis based on numerical computations is performed on the accuracy of resolving the local pressure coefficient and global integrated force coefficients for smooth subsonic and non-smooth transonic flows with moving shock waves on a pitching airfoil. For smooth subsonic flows, the Fourier TSM method offers a significant accuracy advantage over the BDF method for the prediction of both the local pressure coefficient and integrated force coefficients. For transonic flows where the motion of the discontinuous shock wave contributes significant higherorder harmonic contents to the local pressure fluctuations,a sufficient number of modes must be included before the Fourier TSM provides an advantage over the BDF method.The Fourier TSM, however, still offers better accuracy than the BDF method for integrated force coefficients even for transonic flows. A problem of non-symmetric solutions for symmetric periodic flows due to the use of odd numbers of intervals is uncovered and analyzed. A frequency-searching method is proposed for problems where the frequency is not known a priori. The method is tested on the vortex shedding problem of the flow over a circular cylinder.
基金supported by NNSF of China(No.11771469)supported by NNSF of China(No.11971147)Chinese Academy of Sciences(No.QYZDJ-SSW-SYS021)
文摘In this paper,we construct stationary classical solutions of the shallow water equation with vanishing Froude number Fr in the so-called lake model.To this end we need to study solutions to the following semilinear elliptic problem -ε^2div(△u/b)=b(u-qlog1/ε)^p+,in Ω,u=0,on aΩfor small ε>0,where p>1,div(△q/b)=0 and ΩcR^2 is a smooth bounded domain.We show that if q^2/b has m strictly local minimum(maximum)points Zi,i=1,...,m,then there is a stationary classical solution approximating stationary m points vortex solution of shallow water equations with vorticity m∑i=1π2q(zi)/b(zi).Moreover,strictly local minimum points of q^2/b on the boundary can also give vortex solutions for the shallow water equation.
