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From dust devil to sustainable swirling wind energy.

Zhang M, Luo X, Li T, Zhang L, Meng X, Kase K, Wada S, Yu CW, Gu Z - Sci Rep (2015)

Bottom Line: Here, a concept of sustained dust-devil-like whirlwind is proposed for the energy generation.A prototype of a circular shed with pre-rotation vanes has been devised to generate the whirlwind flow by heating the air inflow into the circular shed.The pre-rotation vanes can provide the air inflow with angular momentum.

View Article: PubMed Central - PubMed

Affiliation: School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, China.

ABSTRACT
Dust devils are common but meteorologically unique phenomena on Earth and on Mars. The phenomenon produces a vertical vortex motion in the atmosphere boundary layer and often occurs in hot desert regions, especially in the afternoons from late spring to early summer. Dust devils usually contain abundant wind energy, for example, a maximum swirling wind velocity of up to 25 m/s, with a 15 m/s maximum vertical velocity and 5 m/s maximum near-surface horizontal velocity can be formed. The occurrences of dust devils cannot be used for energy generation because these are generally random and short-lived. Here, a concept of sustained dust-devil-like whirlwind is proposed for the energy generation. A prototype of a circular shed with pre-rotation vanes has been devised to generate the whirlwind flow by heating the air inflow into the circular shed. The pre-rotation vanes can provide the air inflow with angular momentum. The results of numerical simulations and experiment illustrate a promising potential of the circular shed for generating swirling wind energy via the collection of low-temperature solar energy.

No MeSH data available.


Related in: MedlinePlus

Modelling heating shed experiment.(a), Wind velocities for two different electric heating powers. Two different electric heating pads with R = 0.5 m and R = 1 m were investigated in the experiments with ΔT = 50 K. (b), Box-and-whisker diagram of the measured swirling velocity, Uτ, and vertical velocity, UY were respectively obtained by experiments in comparison with the corresponding simulation values. Each plot shows the statistical results of 300 measurement values. The top and bottom lines(whiskers) represent the highest and lowest values, and the three horizontal lines in the box represent the upper and lower quartiles and the median. The result shows the validity of the numerical simulation. Due to the ideal wall friction effect of the induced duct in the small-scale modelling of the heating shed by simulation, the simulated vertical velocity, UY was greater than the average value measured in the experiment.
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f3: Modelling heating shed experiment.(a), Wind velocities for two different electric heating powers. Two different electric heating pads with R = 0.5 m and R = 1 m were investigated in the experiments with ΔT = 50 K. (b), Box-and-whisker diagram of the measured swirling velocity, Uτ, and vertical velocity, UY were respectively obtained by experiments in comparison with the corresponding simulation values. Each plot shows the statistical results of 300 measurement values. The top and bottom lines(whiskers) represent the highest and lowest values, and the three horizontal lines in the box represent the upper and lower quartiles and the median. The result shows the validity of the numerical simulation. Due to the ideal wall friction effect of the induced duct in the small-scale modelling of the heating shed by simulation, the simulated vertical velocity, UY was greater than the average value measured in the experiment.

Mentions: A heating shed model with R = 2 m (Supplementary Figure 1a), was set up to test the dust-devil like swirling buoyant jet. The experiments with ΔT = 50 K, 60 K, and 70 K were conducted. The swirling velocity and vertical velocity at two points were measured as marked in Supplementary Figure 1b. Measurements obtained from the experiment with ΔT = 50 K were shown in Fig. 3a as an illustration. These results were plotted as a box-and-whisker diagram and then compared with the simulation values, as illustrated in Fig. 3b. The swirling velocity and vertical velocity tended to increase with the heating temperature difference and this could aid the efficacy of the swirling wind energy generation. A video of the generated swirling wind was recorded and the wind was compared with a typical dust devil found in nature (Supplementary Video 1).


From dust devil to sustainable swirling wind energy.

Zhang M, Luo X, Li T, Zhang L, Meng X, Kase K, Wada S, Yu CW, Gu Z - Sci Rep (2015)

Modelling heating shed experiment.(a), Wind velocities for two different electric heating powers. Two different electric heating pads with R = 0.5 m and R = 1 m were investigated in the experiments with ΔT = 50 K. (b), Box-and-whisker diagram of the measured swirling velocity, Uτ, and vertical velocity, UY were respectively obtained by experiments in comparison with the corresponding simulation values. Each plot shows the statistical results of 300 measurement values. The top and bottom lines(whiskers) represent the highest and lowest values, and the three horizontal lines in the box represent the upper and lower quartiles and the median. The result shows the validity of the numerical simulation. Due to the ideal wall friction effect of the induced duct in the small-scale modelling of the heating shed by simulation, the simulated vertical velocity, UY was greater than the average value measured in the experiment.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4321178&req=5

f3: Modelling heating shed experiment.(a), Wind velocities for two different electric heating powers. Two different electric heating pads with R = 0.5 m and R = 1 m were investigated in the experiments with ΔT = 50 K. (b), Box-and-whisker diagram of the measured swirling velocity, Uτ, and vertical velocity, UY were respectively obtained by experiments in comparison with the corresponding simulation values. Each plot shows the statistical results of 300 measurement values. The top and bottom lines(whiskers) represent the highest and lowest values, and the three horizontal lines in the box represent the upper and lower quartiles and the median. The result shows the validity of the numerical simulation. Due to the ideal wall friction effect of the induced duct in the small-scale modelling of the heating shed by simulation, the simulated vertical velocity, UY was greater than the average value measured in the experiment.
Mentions: A heating shed model with R = 2 m (Supplementary Figure 1a), was set up to test the dust-devil like swirling buoyant jet. The experiments with ΔT = 50 K, 60 K, and 70 K were conducted. The swirling velocity and vertical velocity at two points were measured as marked in Supplementary Figure 1b. Measurements obtained from the experiment with ΔT = 50 K were shown in Fig. 3a as an illustration. These results were plotted as a box-and-whisker diagram and then compared with the simulation values, as illustrated in Fig. 3b. The swirling velocity and vertical velocity tended to increase with the heating temperature difference and this could aid the efficacy of the swirling wind energy generation. A video of the generated swirling wind was recorded and the wind was compared with a typical dust devil found in nature (Supplementary Video 1).

Bottom Line: Here, a concept of sustained dust-devil-like whirlwind is proposed for the energy generation.A prototype of a circular shed with pre-rotation vanes has been devised to generate the whirlwind flow by heating the air inflow into the circular shed.The pre-rotation vanes can provide the air inflow with angular momentum.

View Article: PubMed Central - PubMed

Affiliation: School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, China.

ABSTRACT
Dust devils are common but meteorologically unique phenomena on Earth and on Mars. The phenomenon produces a vertical vortex motion in the atmosphere boundary layer and often occurs in hot desert regions, especially in the afternoons from late spring to early summer. Dust devils usually contain abundant wind energy, for example, a maximum swirling wind velocity of up to 25 m/s, with a 15 m/s maximum vertical velocity and 5 m/s maximum near-surface horizontal velocity can be formed. The occurrences of dust devils cannot be used for energy generation because these are generally random and short-lived. Here, a concept of sustained dust-devil-like whirlwind is proposed for the energy generation. A prototype of a circular shed with pre-rotation vanes has been devised to generate the whirlwind flow by heating the air inflow into the circular shed. The pre-rotation vanes can provide the air inflow with angular momentum. The results of numerical simulations and experiment illustrate a promising potential of the circular shed for generating swirling wind energy via the collection of low-temperature solar energy.

No MeSH data available.


Related in: MedlinePlus