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Accuracy improvement capability of advanced projectile based on course correction fuze concept.

Elsaadany A, Wen-jun Y - ScientificWorldJournal (2014)

Bottom Line: The simulation results show that the impact accuracy of a conventional projectile using these course correction modules can be improved.The drag ring brake is found to be highly capable for range correction.On the other hand, the canard based-correction fuze is found to have a higher effect on the projectile drift by modifying its roll rate.

View Article: PubMed Central - PubMed

Affiliation: Nanjing University of Science and Technology, Nanjing 210094, China.

ABSTRACT
Improvement in terminal accuracy is an important objective for future artillery projectiles. Generally it is often associated with range extension. Various concepts and modifications are proposed to correct the range and drift of artillery projectile like course correction fuze. The course correction fuze concepts could provide an attractive and cost-effective solution for munitions accuracy improvement. In this paper, the trajectory correction has been obtained using two kinds of course correction modules, one is devoted to range correction (drag ring brake) and the second is devoted to drift correction (canard based-correction fuze). The course correction modules have been characterized by aerodynamic computations and flight dynamic investigations in order to analyze the effects on deflection of the projectile aerodynamic parameters. The simulation results show that the impact accuracy of a conventional projectile using these course correction modules can be improved. The drag ring brake is found to be highly capable for range correction. The deploying of the drag brake in early stage of trajectory results in large range correction. The correction occasion time can be predefined depending on required correction of range. On the other hand, the canard based-correction fuze is found to have a higher effect on the projectile drift by modifying its roll rate. In addition, the canard extension induces a high-frequency incidence angle as canards reciprocate at the roll motion.

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Altitude versus range.
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fig10: Altitude versus range.

Mentions: During the course correction phase, semicircular plates will deploy from the module. The plates create a blunt cross-sectional area in front of the projectile, thus creating more drag and effectively slowing the projectile. The analysis is carried out for deploying the drag brake at various stages of trajectory and once the drag ring module is deployed, it will remain open throughout the trajectory, and then the projectile will slow down, ultimately bringing it closer to the intended target. The results show that the drag ring brakes are found to be highly capable for range correction. The deploying of the drag brake in early stage of trajectory results in maximum range correction (Figure 10). Hence, maximum range correction is observed at the earliest occasion time, where occasion time of 20 seconds gives correction of 1609 m (i.e., 5.34% of the total nominal range). The differences in velocities due to drag brakes are shown in Figure 11. It is observed that deployment of drag brake throughout the flight reduces the remaining velocity, by nearly 44 m/sec, which gives the required correction in range. From the results listed in Table 2, we can conclude that the occasion time can be predefined depending on required correction of range.


Accuracy improvement capability of advanced projectile based on course correction fuze concept.

Elsaadany A, Wen-jun Y - ScientificWorldJournal (2014)

Altitude versus range.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4109594&req=5

fig10: Altitude versus range.
Mentions: During the course correction phase, semicircular plates will deploy from the module. The plates create a blunt cross-sectional area in front of the projectile, thus creating more drag and effectively slowing the projectile. The analysis is carried out for deploying the drag brake at various stages of trajectory and once the drag ring module is deployed, it will remain open throughout the trajectory, and then the projectile will slow down, ultimately bringing it closer to the intended target. The results show that the drag ring brakes are found to be highly capable for range correction. The deploying of the drag brake in early stage of trajectory results in maximum range correction (Figure 10). Hence, maximum range correction is observed at the earliest occasion time, where occasion time of 20 seconds gives correction of 1609 m (i.e., 5.34% of the total nominal range). The differences in velocities due to drag brakes are shown in Figure 11. It is observed that deployment of drag brake throughout the flight reduces the remaining velocity, by nearly 44 m/sec, which gives the required correction in range. From the results listed in Table 2, we can conclude that the occasion time can be predefined depending on required correction of range.

Bottom Line: The simulation results show that the impact accuracy of a conventional projectile using these course correction modules can be improved.The drag ring brake is found to be highly capable for range correction.On the other hand, the canard based-correction fuze is found to have a higher effect on the projectile drift by modifying its roll rate.

View Article: PubMed Central - PubMed

Affiliation: Nanjing University of Science and Technology, Nanjing 210094, China.

ABSTRACT
Improvement in terminal accuracy is an important objective for future artillery projectiles. Generally it is often associated with range extension. Various concepts and modifications are proposed to correct the range and drift of artillery projectile like course correction fuze. The course correction fuze concepts could provide an attractive and cost-effective solution for munitions accuracy improvement. In this paper, the trajectory correction has been obtained using two kinds of course correction modules, one is devoted to range correction (drag ring brake) and the second is devoted to drift correction (canard based-correction fuze). The course correction modules have been characterized by aerodynamic computations and flight dynamic investigations in order to analyze the effects on deflection of the projectile aerodynamic parameters. The simulation results show that the impact accuracy of a conventional projectile using these course correction modules can be improved. The drag ring brake is found to be highly capable for range correction. The deploying of the drag brake in early stage of trajectory results in large range correction. The correction occasion time can be predefined depending on required correction of range. On the other hand, the canard based-correction fuze is found to have a higher effect on the projectile drift by modifying its roll rate. In addition, the canard extension induces a high-frequency incidence angle as canards reciprocate at the roll motion.

Show MeSH