Aerodynamic Analysis of Manta Ray …
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(a) Zimmerman
(b) Manta A
(c) Manta B
Fig. 4 Wake visualization
0.938π as seen from Fig. 3a. Hence, the lift curve slope of both the manta planforms
proves to be more effective, outperforming the Zimmerman planform by 60% due to
higher aspect ratio. The lift curve of the manta planforms reaches a maximum value
of C L at 25°, at which point its value exceeds that of the Zimmerman by 17%, as
seen from Fig. 3a. The difference between the lift curves is truly incontrovertible at
15°, where the difference reaches a maximum value of 45% of that of base planform.
Second, the drag characteristics of the planforms were compared as the coefficient
of drag is important for determining the power consumption of the MAV. The total
surface area of the Manta A and Manta B planforms are 50.9% and 46% more than
the Zimmerman planform, respectively, and this might have implications in the drag
performance. From the drag polar graph in Fig. 3c, it is evident that the zero-lift drag
is lower for the base planform in comparison to both the manta planforms which can
be attributed to the smaller area of the base planform.
Third, the C L /C D ratios were compared as they are important in determining the
operational range of the MAV. From the C L /C D vs angle of attack graph, Fig. 3d, it
is evident that the manta ray-inspired planforms have higher efficiency at angles
between 10 and 20 with the peak value being 5.59% higher than Zimmerman
planform which occurs at angle of attack 10°.
It is important to study the wake of the planform in order to understand the effect
of drag on the geometry. As seen from Fig. 4, the intensity of wake is more for the
modified planforms which explains the higher zero-lift drag observed in Fig. 3c. The
width of the wake is higher for the manta planforms due to their larger span. Also, the
wake diminishes more rapidly for the Zimmerman planform which can be attributed
to the larger area and span of the manta planforms.
5 Conclusion
From the study, it is evident that there is a change in the aerodynamic performance
of the modified planforms. Both the manta planforms differ from the Zimmerman
planforms in the following areas:
• The lift curve slope of both the manta planforms is 60% higher than the base
Zimmerman planform, as evident from Fig. 4a. The lift characteristics of both the
315
(a) Zimmerman
(b) Manta A
(c) Manta B
Fig. 4 Wake visualization
0.938π as seen from Fig. 3a. Hence, the lift curve slope of both the manta planforms
proves to be more effective, outperforming the Zimmerman planform by 60% due to
higher aspect ratio. The lift curve of the manta planforms reaches a maximum value
of C L at 25°, at which point its value exceeds that of the Zimmerman by 17%, as
seen from Fig. 3a. The difference between the lift curves is truly incontrovertible at
15°, where the difference reaches a maximum value of 45% of that of base planform.
Second, the drag characteristics of the planforms were compared as the coefficient
of drag is important for determining the power consumption of the MAV. The total
surface area of the Manta A and Manta B planforms are 50.9% and 46% more than
the Zimmerman planform, respectively, and this might have implications in the drag
performance. From the drag polar graph in Fig. 3c, it is evident that the zero-lift drag
is lower for the base planform in comparison to both the manta planforms which can
be attributed to the smaller area of the base planform.
Third, the C L /C D ratios were compared as they are important in determining the
operational range of the MAV. From the C L /C D vs angle of attack graph, Fig. 3d, it
is evident that the manta ray-inspired planforms have higher efficiency at angles
between 10 and 20 with the peak value being 5.59% higher than Zimmerman
planform which occurs at angle of attack 10°.
It is important to study the wake of the planform in order to understand the effect
of drag on the geometry. As seen from Fig. 4, the intensity of wake is more for the
modified planforms which explains the higher zero-lift drag observed in Fig. 3c. The
width of the wake is higher for the manta planforms due to their larger span. Also, the
wake diminishes more rapidly for the Zimmerman planform which can be attributed
to the larger area and span of the manta planforms.
5 Conclusion
From the study, it is evident that there is a change in the aerodynamic performance
of the modified planforms. Both the manta planforms differ from the Zimmerman
planforms in the following areas:
• The lift curve slope of both the manta planforms is 60% higher than the base
Zimmerman planform, as evident from Fig. 4a. The lift characteristics of both the