Although field observations of sudden spillway releases highlighted strong aeration of dam break wave flows, no study investigated these two-phase flow characteristics. New original experiments were conducted down a 24 m long stepped waterways. Dam break wave propagation showed an equivalent flow resistance similar to steady flow conditions (f ~ 0.05). Detailed unsteady air-water flow measureme...

Abstract Aeration is the process of increasing dissolved oxygen (DO) content water, which an important water quality parameter for survival aquatic life. In this process, large amounts air bubbles develop; as a result, contact surface area increases, and hence water-air-mass transfer accelerates. There are numerous methods DO concentration in including self-aeration, mechanical aeration, chemic...

Tell: 701-231-8351 Fax: 701-231-1008 E-mail: [email protected] Abstract: Impact of artificial circulation on total algal biomass (as chlorophyll a integrated over depth) in a small eutrophic impoundment in the Northern Great Plains, was monitored over three consecutive summers. Chlorophyll a concentration and nutrient concentrations were measured at depths along water columns under aerated and ...

Although there appears to be some evidence to suggest that the concentration of CO2 in the soil may have A model that couples the diffusion of O2 to plant roots at the an effect on plant growth, the major effect of poor microscale to diffusion of O2 through the soil at the macroscale is derived. The solution is complex, but if the length scales (Zr and Zm; aeration on plant growth is the lack o...

As the number of leaking underground fuel tank sites with MTBE contamination continues to grow, there is a need to develop cost-effective solutions for treatment of soil and water contamination. MTBE poses special challenges due to its physicochemical properties, in particular high solubility and low Henry’s constant, low affinity for sorption, and very slow rate of microbial degradation. Advan...

Email: [email protected] Abstract: To evaluate the diurnal and seasonal Dissolved Oxygen (DO) variations and their effects on water quality, a comprehensive study was conducted in a eutrophic polymictic reservoir under artificially aerated and non-aerated conditions. The effect of aeration among sampling locations and along the water column of DO and DO saturation and diurnal variation...

Because surface-applied manures can contribute to phosphorus (P) in runoff, we examined mechanical aeration of grasslands for reducing P transport by increasing infiltration of rainfall and binding of P with soil minerals. The effects of three aeration treatments and a control (aeration with cores, continuous-furrow "no-till" disk aeration perpendicular to the slope, slit aeration with tines, a...

Three different aeration plates are used to study their effect on gas holdup and flow regime transition in fiber suspensions. The aeration plates differ by their open-area ratios (A=0.57%, 0.99%, and 2.14%), where the hole diameter remains the same while the number of holes increase. Experiments are performed using three different Rayon fiber lengths (L=3, 6, and 12mm) over a range of superfici...

Construction in urban areas usually results in compacted soil, which restricts plant growth and infiltration. Nutrients may be lost in storm runoff water and sediment. The purpose of this study was to determine if existing lawns benefit from aeration and surface compost additions without the negative impact of nutrient loss in runoff. Four sets of lawns were compared, with or without compost pl...