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Crude Oil
Published in Anco S. Blazev, Energy Security for The 21st Century, 2021
Such shock waves are created by a compressed-air gun which shoots pulses of air into the water (for exploration over water). Thumper trucks are used to slam heavy plates into the ground (for exploration over land). Explosives can be detonated in holes drilled into the ground (for exploration over land) or thrown overboard (for exploration over water) to create shock waves.
Fossil Energy Markets
Published in Anco S. Blazev, Global Energy Market Trends, 2021
Such shock waves are created by a compressed-air gun which shoots pulses of air into the water (for exploration over water). Thumper trucks are used to slam heavy plates into the ground (for exploration over land). Explosives can be detonated in holes drilled into the ground (for exploration over land) or thrown overboard (for exploration over water) to create shock waves.
Noise and vibration
Published in Sue Reed, Dino Pisaniello, Geza Benke, Kerrie Burton, Principles of Occupational Health & Hygiene, 2020
To alleviate this: Use larger, slower machines rather than small, fast ones.Run machines at lower speeds, but with higher torque.Air guns with air channels around the central channel reduce noise by not having all the air concentrated at high speed through the central air channel but spreading the flow of air through several channels around the central orifice at lower speed while not reducing effectiveness. The air gun on the left in Figure 12.9 has air channels around the central orifice. This lowers the speed of the air and changes the pitch of the sound. This type of air gun can be up to 7 dB quieter than the ‘traditional’ air gun shown on the right.
Effect of curvature radius and angle on aerodynamic characteristics of a sphere travelling in a branched tube system
Published in Engineering Applications of Computational Fluid Mechanics, 2023
Thi Thanh Giang Le, Jihoon Kim, Gi-Deuk Park, Woojin Sung, Minki Cho, Hyoungsoon Lee, Jaiyoung Ryu
Although the validation with flow over a sphere at subsonic to supersonic Mach numbers (ranging from 0.29 to 3.96) showed the adequacy of our overset method and numerical setup to provide accurate drag results over a large range of Mach numbers (0.7 to 2.5), it has a limitation. The experiment involved a sphere placed in a free domain, not in a bounded tube. To demonstrate the capability of our method to capture the flow and drag of an object moving in compressible flow inside a tube, the experimental and simulation data from the in-pipe projectile (Hruschka & Klatt, 2019) were used. This experiment involved launching an axisymmetric projectile of ∅4.5 × 5.6 mm using a compressed air gun into a ∅16 × 3000-mm tube. The in-pipe drag was calculated by measuring the velocity before and after the projectile went in and out of the 3000-mm tube for Mach number from 0.5 to 1.5. However, for the simulation, the compressed air gun was not considered, and instead, the projectile was placed 150 mm from the left end of the tube and instantly moved until the drag reached a stationary value. Figure 6a shows the dimension of the 3D projectile and the boundary conditions of the simulations. As demonstrated in Figure 6b, our current simulation results show excellent agreement with the experimental data. Moreover, compared to the results of the 2D axisymmetric and projectile-fixed coordinate conducted by Hruschka and Klatt (2019), our 3D simulation results show a better match with the experimental data and the fitting curve.
Experimental and analytical studies of syntactic foam core composites for impact loading
Published in International Journal of Crashworthiness, 2022
Daniel Paul, Velmurugan R, N. K. Gupta
For ballistic impact, the test samples are square plates and attached to the test fixture using a metallic frame and clamps as shown in Figure 5. The dimensions of the samples are 150mm × 150mm. The sample is placed between a rigid fixture and a metallic frame and held tightly using four C-clamps. The projectile is fired from an air-gun using compressed air. A cylindrical metal projectile having an ogival head is used as shown in Figure 6. This shape is an intermediate between hemispherical and conical-shaped projectiles. Two different projectiles are used for the tests. The 1C1 samples are tested with projectile I while projectile II is used for the other samples as they are tested on a different machine capable of the higher velocities required. A schematic diagram of the gun is shown in Figure 7.
Numerical simulation and test on damage of rotary engine blades impacted by bird
Published in International Journal of Crashworthiness, 2019
Jun Liu, Dudu Zhong, Yulong Li, Zhongbin Tang, Xiaosheng Gao, Zhixue Zhang, Fuzheng Huang
The bird impact test was performed at Northwestern Polytechnical University. The objective of the test is to obtain the dynamic damage of the engine blade subjected to bird strike load. The arrangement of the test equipment is shown in Figure 9. The gas gun system consists of a compressed air gun with the supporting compressor, instrumentation and control systems. The compressor pumps air into the storage tank. A valve located between the driving air storage tank and the breech of the gun is designed to drive the high pressure air from the storage tank into the gun. After the desired air pressure is reached in the pressure chamber, the pressure release valve will open and the gas will expand in the barrel to push the projectile forward. The bird launcher includes the projectile and the sabot with a required mass and must accelerate to a desired velocity. Before impacting on the target, the bird launcher cannot induce any projectile breakup or severe distortion. In the meantime, the projectile must be launched at the desired orientation.