• Water for future
• /
• v.22 no.2
• /
• pp.233-239
• /
• 1989

The partial differential equation of the groundwater flow was reduced to an ordinary differential equation by the Boltzmann transformation. Its numerical solutions were obtained by the finite difference method and the new method to get the initial missing slope using the Richardson method and the finite difference equation was proposed. The solutions computed by the newly proposed method were compared with investigator's computations and they showed a satisfactory agreement and that the proposed method is easy and simple to get solutions.

• Journal of Korean Society for Atmospheric Environment
• /
• v.17 no.2
• /
• pp.223-231
• /
• 2001

In order to provide some insights into the influence of electric field, gas composition, and gas temperature on electron energy distribution and electron transport characteristics, the Boltzmann equation was solved by using cross section data for electron collisions, Critical electric fields for the corona development in dry air and flue gas are 150 and 80 Td, respectively. It was seen that the decrease of critical electric field in flue gas is mainly caused by the $H_2O$ addition through the comparison of ionization and attachment coefficients of gas components. Increase of $O_2$, $H_2O$, and $CO_2$ contents in gas affected discharge characteristics according to their reciprocal characteristics between lowering the ionization threshold and increasing the electro-negativity. As electric field increases, electrons with higher energies in the electron energy distribution also increase. The mean and characteristic electron energies also linearly increase with electric field. The variation of flue gas temperature did rarely affect on the electron energy distribution function and electron transport characteristics, because the gas temperature is several hundreds or thousands times lower than the electron temperature.