The Thai traditional rocket (Bang Fai) or local rocket festival is well known in Northeast Thailand, which is held annually during the months of April to June for highest altitude competition in several categories by their sizes and types. The aims of this paper are to analyze the aerodynamics characteristics of the local rocket designing by using CFD, then construct the rocket and perform the experimental testing. There are 13 rocket models with different nose cones and fins including the traditional rocket model. The simulations were performed at a velocity of 128 kt (66 m/s). From simulation results, the rocket model with ogive nose cone has the lowest turbulence intensity. Although the turbulence intensity from different fin designs are not significantly difference, the clipped triangular fin model yields the smallest intensity region behind the rocket. It is found that the model with ogive nose cone with elliptical fin has the lowest drag force of 6.37 N while the ogive nose cone with clipped triangular fin and the original design drag are 7.40 N and 8.50 N respectively. Even though, all of rocket designs in this study have stability margin higher than the recommended stability margin, the ogive nose cone and clipped triangular fin model has the highest stability margin of 6.0, which is chosen for rocket construction and experimental testing. The performance between the proposed rocket design model and the original local rocket are proven by launching experiment. The rocket contains 6 kg of solid fuel, which is classified as Bang Fai Muen. By observing the exhaust smoke, launchings of the rocket showed that the original rocket reached the altitude approximately 600 m and the new design reached around 700 m. Therefore, the ogive nose cone is capable of reducing drag while the clipped triangular fin can increase the directional stability during the launch, which permit the rocket to achieve higher altitude.
Low Altitude Local Rocket Aerodynamics Analysis and Experimental Testing
Published: 03 July 2021 by MDPI in Innovation Aviation & Aerospace Industry - International Conference 2021 session Aerospace Engineering
https://doi.org/10.3390/IAAI-2021-10579 (registering DOI)
Keywords: Bang Fai, Rocket Design; CFD; Stability Margin