ATOMIZATION OF GELLED PROPELLANTS FROM SWIRL INJECTORS WITH LEAF SPRING IN SWIRL CHAMBER

2011 ◽  
Vol 21 (11) ◽  
pp. 949-969 ◽  
Author(s):  
Li-jun Yang ◽  
Qingfei Fu ◽  
Wei Zhang ◽  
Ming-long Du ◽  
Ming-xi Tong
Keyword(s):  
Leaf Spring ◽  
Swirl Injectors ◽  
Swirl Chamber ◽  
Gelled Propellants

Spray characteristics of gelled propellants in swirl injectors

Fuel ◽  
2012 ◽  
Vol 97 ◽  
pp. 253-261 ◽  
Author(s):  
Li-jun Yang ◽  
Qing-fei Fu ◽  
Yuan-yuan Qu ◽  
Wei Zhang ◽  
Ming-long Du ◽  
...  
Keyword(s):  
Spray Characteristics ◽  
Swirl Injectors ◽  
Gelled Propellants

scholarly journals Study on dynamic characteristics of leaf spring system in vibration screen

2021 ◽  
pp. 146134842110229
Author(s):  
Jiacheng Zhou ◽  
Chao Hu ◽  
Ziqiu Wang ◽  
Zhengfa Ren ◽  
Xiaoyu Wang ◽  
...  
Keyword(s):  
Dynamic Characteristics ◽  
Vertical Direction ◽  
Maximum Amplitude ◽  
Exciting Force ◽  
Mode Shapes ◽  
Leaf Spring ◽  
Amplification Factors ◽  
Simulation And Experiment ◽  
Exciting Forces ◽  
Spring System

By studying dynamic characteristics of the leaf spring system, a new elastic component is designed to reduce the working load and to a certain extent to ensure the linearity as well as increase the amplitude in the vertical and horizontal directions in vibration screen. The modal parameters, amplitudes, and amplification factors of the leaf spring system are studied by simulation and experiment. The modal results show that the leaf spring system vibrates in horizontal and vertical directions in first and second mode shapes, respectively. It is conducive to loosening and moving the particles on the vibration screen. In addition, it is found that the maximum amplitude and amplification factor in the horizontal direction appear at 300 r/min (5 Hz) while those in the vertical direction appear at 480 r/min (8 Hz), which are higher than those in the disc spring system. Moreover, the amplitude of the leaf spring system increases proportionally with the increase of exciting force while the amplification factors are basically the same under different exciting forces, indicating the good linearity of the leaf spring system. Furthermore, the minimum exciting force occurs in the leaf spring system under the same amplitude by comparing the exciting force among different elastic components. The above works can provide guidance for the industrial production in vibration screen.

Modal Strain Energy based Crack Inspection in Mono Composite Leaf Spring

2021 ◽  
Author(s):  
N. I. Jamadar ◽  
S. B. Kivade ◽  
K. K. Dhande ◽  
Khaleefah Manhal ◽  
Rakesh Roshan
Keyword(s):  
Strain Energy ◽  
Leaf Spring ◽  
Modal Strain Energy

scholarly journals Individual stiffness optimization of dorsal leaf spring ankle–foot orthoses in people with calf muscle weakness is superior to standard bodyweight-based recommendations

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Niels F. J. Waterval ◽  
Merel-Anne Brehm ◽  
Jaap Harlaar ◽  
Frans Nollet
Keyword(s):  
Muscle Weakness ◽  
Energy Cost ◽  
Activity Level ◽  
Calf Muscle ◽  
Leaf Spring ◽  
Foot Orthoses ◽  
Ankle Foot Orthoses ◽  
The Individual ◽  
Optimal Stiffness ◽  
Walking Energy Cost

Abstract Background In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle–foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness. Methods Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected. Results In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s, p = 0.003). Additionally, a larger ankle range of motion (+ 1.3 ± 0.3 degrees, p < 0.001) and higher ankle power (+ 0.16 ± 0.04 W/kg, p < 0.001) were found with the experimentally optimized stiffness compared to the supplier recommended stiffness. Conclusions In people with calf muscle weakness, current supplier’s recommendations for the CA7 stiffness level result in the provision of DLS-AFOs that are too stiff and only achieve 80% of the reduction in energy cost achieved with an individual optimized stiffness. It is recommended to experimentally optimize the CA7 stiffness in people with calf muscle weakness in order to maximize treatment outcomes. Trial registration Nederlands Trial Register 5170. Registration date: May 7th 2015. http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=5170.

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