Dynamic Flow Characteristics of Liquefied Sand Under the Extrema Large Deformation in the Cyclic Torsional Shear Tests

2018 ◽  
pp. 318-330
Author(s):  
Haiyang Zhuang ◽  
Qifei Liu ◽  
Xuchao Xue ◽  
Guoxing Chen
Keyword(s):  
Large Deformation ◽  
Flow Characteristics ◽  
Dynamic Flow ◽  
Shear Tests ◽  
Torsional Shear

Numerical Investigation of Positive Displacement Rotary Lobe Pump With Twisted Rotors

2014 ◽  
Author(s):  
Xiaojun Jiang ◽  
Yi Li ◽  
Zhaohui He ◽  
Cui Baoling ◽  
Wenlong Dong
Keyword(s):  
Flow Structure ◽  
Stokes Equations ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Dynamic Flow ◽  
Flow Fluctuation ◽  
Flow Field Characteristics ◽  
Lobe Pump ◽  
The Impact

The three-dimensional flow field characteristics are obtained by performing numerical simulation of flow in a lobe pump with twisted rotors. The relationship between the dynamic flow structure and the flow fluctuation is explored. Actually, the viscous incompressible Navier-Stokes equations are solved within an unsteady flow model. The dynamic mesh technique is applied to obtain the dynamic flow structure. By comparing the simulated results of straight rotor with those of twisted rotor, the effect of rotor shape on the flow fluctuation was revealed. Finally, the impact of the lobes number of rotors on flow pulsations is discussed. The results show that there is an intrinsic relationship between the flow fluctuation and the vortex in the lobe pump. The use of twisted rotors can effectively improve the internal flow characteristics of lobe pump and reduce flow fluctuation. With the increase of the number of lobes, the lobe pump output is more stable and capacity has been improved.

scholarly journals UNDRAINED CYCLIC TORSIONAL SHEAR TESTS ON LIQUEFACTION RESISTANCE OF SAND UNDER SEQUENCED EARTHQUAKE MOTIONS

2016 ◽  
Vol 72 (2) ◽  
pp. I_366-I_371
Author(s):  
Takaaki KOBAYASHI ◽  
Shinji SASSA ◽  
Keita WATANABE ◽  
Hiroyuki YAMAZAKI
Keyword(s):  
Shear Tests ◽  
Liquefaction Resistance ◽  
Torsional Shear

Post-cyclic volumetric strain of calcareous sand using hollow cylindrical torsional shear tests

2019 ◽  
Vol 124 ◽  
pp. 162-171 ◽  
Author(s):  
Habib Shahnazari ◽  
Reza Rezvani ◽  
Mohammad Amin Tutunchian
Keyword(s):  
Volumetric Strain ◽  
Shear Tests ◽  
Calcareous Sand ◽  
Torsional Shear

Torsional Shear Tests on Laminated Veneer Lumber Using a Universal-Type Test Machine

2013 ◽  
Vol 25 (12) ◽  
pp. 1979-1983 ◽  
Author(s):  
Zhuo Yang ◽  
Peggi L. Clouston ◽  
Alexander C. Schreyer
Keyword(s):  
Test Machine ◽  
Shear Tests ◽  
Laminated Veneer Lumber ◽  
Torsional Shear ◽  
Type Test

scholarly journals On the Measurement and Modeling of High-Pressure Flows in Poppet Valves Under Steady-State and Transient Conditions

2017 ◽  
Vol 139 (7) ◽  
Author(s):  
Stephan Mohr ◽  
Henry Clarke ◽  
Colin P. Garner ◽  
Neville Rebelo ◽  
Andrew M. Williams ◽  
...  
Keyword(s):  
Steady State ◽  
Transient Flow ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Valve Lift ◽  
Transient Pressure ◽  
Dynamic Flow ◽  
Steady State Flow ◽  
State Flow ◽  
Piston Cylinder

Flow coefficients of intake valves and port combinations were determined experimentally for a compressed nitrogen engine under steady-state and dynamic flow conditions for inlet pressures up to 3.2 MPa. Variable valve timing was combined with an indexed parked piston cylinder unit for testing valve flows at different cylinder volumes while maintaining realistic in-cylinder transient pressure profiles by simply using a fixed area outlet orifice. A one-dimensional modeling approach describing three-dimensional valve flow characteristics has been developed by the use of variable flow coefficients that take into account the propagation of flow jets and their boundaries as a function of downstream/upstream pressure ratios. The results obtained for the dynamic flow cases were compared with steady-state results for the cylinder to inlet port pressure ratios ranges from 0.18 to 0.83. The deviation of flow coefficients for both cases is discussed using pulsatile flow theory. The key findings include the followings: (1) for a given valve lift, the steady-state flow coefficients fall by up to 21% with increasing cylinder/manifold pressure ratios within the measured range given above and (2) transient flow coefficients deviated from those measured for the steady-state flow as the valve lift increases beyond a critical value of approximately 0.5 mm. The deviation can be due to the insufficient time of the development of steady-state boundary layers, which can be quantified by the instantaneous Womersley number defined by using the transient hydraulic diameter. We show that it is possible to predict deviations of the transient valve flow from the steady-state measurements alone.

New Methods of Assessing Static and Dynamic Flow Characteristics of Textiles

2000 ◽  
Vol 70 (1) ◽  
pp. 53-58 ◽  
Author(s):  
Krzysztof Gniotek ◽  
Pawel Tokarski
Keyword(s):  
Flow Characteristics ◽  
Dynamic Flow ◽  
New Methods
Sign in / Sign up

Export Citation Format

Share Document