We also used the model to optimize the design and operation of photobioreactors for productivity maximization, developing strategies to manage the biomass concentration and the mixing frequency.
A potential source of this problem was identified as the representation of the scalar mixing frequency as a constant ratio of the scalar to flow time.
Significant enhancement of algae production rate with mixing is observed for small values of the ratio of illuminated layer depth to total fluid depth; however, growth rate enhancement saturates beyond a certain mixing frequency.
It is found that a suitable value for the model constant c that controls the mixing frequency can be derived using the local normalized scalar variance, and that the model constant a controls the localness of the model.
Direct numerical simulation (DNS) data-sets were used to provide both initial conditions and inputs needed over the course of the runs, including the mean flow velocities, mixing frequency, and the turbulent diffusion coefficient.
Mechanical tissue loosening involved gentle tube flicking and slow pipetting with a cut pipet tip approximately every 15 20 min. Too vigorous mechanical manipulation resulted in shearing of fibers; mixing frequency was determined based upon tissue appearance using Nomarski optics during dissociation.
The model is designed to target initial announcements of GDP in a mixed-frequency framework.
Moreover, mixed-frequency excitation is used to demonstrate a tunable wide band filter for low frequency applications.
According to the numerical studies performed on periodic excitation, the mixed-frequency harmonic input is preferable to the single-frequency one.
Versatility of the method is demonstrated by considering the cases such as mixed-frequency excitation and an MDOF oscillator with multiple bilinear springs.
