Collecting waste water with a certain c onc entration of organic pollutants COD (chemical oxygen demand), static adsorption, static biodegradation and dynamic soil column experiments were made in laborato ry, we rese...Collecting waste water with a certain c onc entration of organic pollutants COD (chemical oxygen demand), static adsorption, static biodegradation and dynamic soil column experiments were made in laborato ry, we researched migration and transformation of COD in aerated zone, and put f orward a mathematical model showing the process. The results show that adsorptio n of organism in aerated zone is linear, which is represented by Henry's law s =K dc+s d, adsorption coefficient K d=0.069 3; biodegradati on diagram accord basically with first order kinetics equation c=c 0e -K 1t , biodegradation coefficient K 1 = 0.049 9 d -1 ; dispersio n coefficient D= 0.002 42 m 2/d in experiments. The migration and transform ation of organic pollutants (COD) in aerated zone jointly result from many f actors such as dispersion, adsorption and biodegradation etc..展开更多
For the purpose of time-domain calculation of wave forces on moored ships ina harbor, the 2D/3D coupled numerical model was developed, in which the horizontally 2Dshallow-water wave model based on the improved Boussin...For the purpose of time-domain calculation of wave forces on moored ships ina harbor, the 2D/3D coupled numerical model was developed, in which the horizontally 2Dshallow-water wave model based on the improved Boussinesq equations was adopted for the calculationin the wide region located far from the ships while the 3D numerical model based on theReynolds-Averaged Navier-Stokes (RANS) equations was used in the limited region adjacent to theships. The domain connection technique with overlaping region between different model regions wasapplied and examined. It is shown that the present partially 3D hybrid model saves calculation timesignificantly compared to the full 3D model for the whole region and is capable of reproducing thecharacteristics of 3D and complicated flows around the ships and 3D hydrodynamic loads on them,which cannot be reproduced by the 2D model alone.展开更多
文摘Collecting waste water with a certain c onc entration of organic pollutants COD (chemical oxygen demand), static adsorption, static biodegradation and dynamic soil column experiments were made in laborato ry, we researched migration and transformation of COD in aerated zone, and put f orward a mathematical model showing the process. The results show that adsorptio n of organism in aerated zone is linear, which is represented by Henry's law s =K dc+s d, adsorption coefficient K d=0.069 3; biodegradati on diagram accord basically with first order kinetics equation c=c 0e -K 1t , biodegradation coefficient K 1 = 0.049 9 d -1 ; dispersio n coefficient D= 0.002 42 m 2/d in experiments. The migration and transform ation of organic pollutants (COD) in aerated zone jointly result from many f actors such as dispersion, adsorption and biodegradation etc..
文摘For the purpose of time-domain calculation of wave forces on moored ships ina harbor, the 2D/3D coupled numerical model was developed, in which the horizontally 2Dshallow-water wave model based on the improved Boussinesq equations was adopted for the calculationin the wide region located far from the ships while the 3D numerical model based on theReynolds-Averaged Navier-Stokes (RANS) equations was used in the limited region adjacent to theships. The domain connection technique with overlaping region between different model regions wasapplied and examined. It is shown that the present partially 3D hybrid model saves calculation timesignificantly compared to the full 3D model for the whole region and is capable of reproducing thecharacteristics of 3D and complicated flows around the ships and 3D hydrodynamic loads on them,which cannot be reproduced by the 2D model alone.
