Comparison of specific energy dissipation rate calculation methodologies utilising 2D PIV velocity measurement

Three-dimensional turbulence generated homogeneously by magnetic particles

“…Here, one finds c = 1.1 close to the values found with a boundary forcing (grid turbulence) [35,38]. These estimations of ǫ by five different methods are hardly obtained experimentally [39] and are found here to be all consistent as a consequence of the stationary, homogeneous and isotropic turbulence generated by this forcing in volume. Note that higher turbulence levels can be explored with this forcing (e.g., ǫ ∼ 6 10 −3 m 2 /s −3 for σ u ∼ 0.18 m/s measured with LDV).…”

Estimation of chemical and physical effects of cavitation by analysis of cavitating single bubble dynamics

“…The fluctuating velocity in the liquid at a fixed distance of the maximum simulated bubble radius from the bubble center, was calculated using the radial velocities (available through the rate of change of the bubble radius solved in the present model) over the simulated lifetime of the bubble. These quantities were then used to obtain the turbulent energy dissipation rates (TEDR) (proportional to the velocity cubed divided by the characteristic Eddie length) [33] , [61] . To illustrate such applications of the present model, the contour plot of the turbulent energy dissipation rate as a function of and the ambient pressure is shown in Fig.…”

Numerical and experimental assessment of a miniature bioreactor equipped with a mechanical agitator and non‐invasive biosensors

“…Specifically, for determination of oxygen mass transfer, chemical, dynamic and gas‐balancing methods are widely employed . For quantification of shear rate, particle image velocimetry (PIV) and laser Doppler velocimetry (LDV) are commonly used to test the velocity field in the bioreactor, based on which the shear rate field can be derived mathematically . For measurement of mixing time, pH tracer‐based, conductance probe and color change methods are available .…”

“…[27][28][29] For quantification of shear rate, particle image velocimetry (PIV) and laser Doppler velocimetry (LDV) are commonly used to test the velocity field in the bioreactor, based on which the shear rate field can be derived mathematically. [30][31][32][33][34][35][36] For measurement of mixing time, pH tracer-based, conductance probe and color change methods are available. [37][38][39] Nevertheless, the limited volume of the mini bioreactor makes it inconvenient to carry out the above methods.…”