Home - Tideflex Mixing Systems (TMS)  - WRF Scale Modeling

Figure 1
Three-Dimensional Laser-Induced Fluorescense

Figure 2
Independent Scale Modeling

 

(WRF) Scale Modeling

    Red Valve partnered with the Georgia Institute of Technology on a 2006 Water Research Foundation (WRF) [formerly AwwaRF] report entitled “Physical Modeling of Mixing in Water Storage Tanks”. The research consisted of physical scale model experiments of circular reservoirs, rectangular reservoirs, and standpipes utilizing Three-Dimensional Laser-Induced Fluorescense (3DLIF). Figure 1 shows a schematic and photo of the test setup. Florescent dye is injected into the inflow during tank filling. A laser sheet is scanned thru the model at 40 frames per second. A digital camera is placed perpendicular to the laser sheets and it captures the fluoresced dye which is directional proportional to concentration. There are timing and data acquisition computers that synchronize the snapshots as the laser sheet scans thru the model and each snapshot is captured. Prior scale modeling techniques used conductivity probes that only provided a limited number of data points. With 3DLIF, the entire flow field is captured and literally millions of data points.

    Baseline experiments were run with a single inlet pipe for each tank style. Then, many models were run with varying multiport configurations. The goals of the research were to determine: 1) if multiple ports result in faster mixing, 2) the effect of high and low momentum on mixing and 3) the effect density differences (temperature differences) between inlet water and tank water have on mixing.

    Results showed that a properly designed multiport mixing system results in up to 50% faster mixing compared to a single inlet. In addition, a properly designed mixing system was able to mix tanks when there are temperature differentials between the distribution system water (inlet water) and the existing water within the tank. With this type of temperature differential, single inlet systems produced incomplete mixing which resulted in temperature stratification of the water within the reservoir.

    Independent scale modeling has been done comparing single inlet/outlet designs to the mutliport TMS. Those studies also validated the improved mixing of the TMS (refer to Figure 2).

    Based on the extensive scale modeling completed with the WRF project, and the extensive CFD modeling that we have conducted, Red Valve designs TMS manifold configurations for all tank styles that were identified to produce the fastest mixing. The TMS has been field validated in every tank style with sampling and monitoring studies conducted by water utilities.

US Patent No. 7,104,279
Canada Patent No. 2,409,009