关键词: 制曲车间, 多尘源, 数值模拟, 分布方程, 粉尘扩散, 粉尘质量浓度

Abstract:

In order to reveal the dust transport law and its distribution characteristics in the koji-making workshop, with the koji dismantling process area as the research background, the dust mass concentration equation in the koji-making workshop was established based on the Gaussian model. The Fluent software was used to numerically simulate the dust diffusion process in the koji-making workshop under natural ventilation conditions with different positions and quantities of dust sources, and the theoretically calculated values, numerical simulation results and measured data of dust mass concentration were verified against each other. The concentration distribution and spatial and temporal evolution of dust migration in the koji-making workshop under different working conditions were obtained. The result indicates that when the dust source is located at different positions in the fermentation silos, dust mainly concentrates near the working surface. Compared with the central operation, the near window operation causes a wider area of high concentration of dust in the fermentation silos, and the peak concentration of total dust fluctuated around 200 mg/m³. When the fermentation silos with different relative positions from the aisle are operated near the window, the dust in the aisle is mainly concentrated near the silos. Compared with the operation in a single silo, the multiple dust sources will have a superposition effect on the distribution of the dust in the aisle. Among them, the dust pollution in the aisle is the most serious when the adjacent silos are operated, and the total dust concentration is more than 75 mg/m³. Under single silo, adjacent silo and relative silo working conditions, the dust has been diffused to the whole aisle around the operation time at 525, 470 and 498 s, respectively.

Key words: koji-making workshop, multiple sources of dust production, numerical simulation, distribution equation, dust diffusion, dust mass concentration