To reveal the force chain evolution and dynamic state under granular flow lubrication
an analytical model of granular flow lubrication between sheared parallel plates is established based on the discrete element theory of continuum mechanics. Using this analytical model
the contact force distribution rule
the force chain evolution rule and dynamic state
as well as the force chain distribution and its influence on the granular flow lubrication system
are studied. Numerical analytical results show that the probability distributions of normal contact force
tangential contact force
and contact between granular lubrication medium all obey the power law; the load bearing and dynamic characteristics of granular lubrication system are mainly influenced by normal contact force; and the dynamic state of granular lubrication medium can be transformed into four states of jamming state
quasi-static state
slow flow and fast flow. Under these four flow states
the magnitude of total force chain is large in the jamming state
quasi-static state and slow flow state
but small in the fast flow state. When the dynamic state of granular lubrication medium transforms from fast flow state to slow flow state or quasi-static state
the number of weak force chains is deceased and the number of strong and super force chains is increased. And in the meantime
the flow speed of granular lubrication medium as well as the deconstruction and reconstruction speeds of force chains slows down.
WANG Wei, LIU Xiaojun, JIAO Minghua, et al. Influences of several slider's parameters on particles flow lubrication characteristics [J]. Journal of Mechanical Engineering, 2009, 45(7): 101-107.
TIMMA K, MYANT C, SPIKS H A, et al. Particulate lubricants in cosmetic applications [J]. Tribology International, 2011, 44(12): 1695-1703.
IORDANOFF I, BERTHIER Y, DESCARTES S, et al. A review of recent approaches for modeling solid third bodies [J]. Journal of Tribology, 2002, 124(10): 725-735.
HESHMA H. The rheology and hydrodynamics of dry powder lubrication [J]. Tribology Transactions, 1991, 34(3): 433-439.
WANG Wei, KONG Junchao, GU Wei, et al. Experimental study on macro and micro characteristics of powder lubricant layer in frictional warm interface [J]. Tribology, 2016, 36(2): 233-239.
MENG Fanjing, LIU Kun, WANG Wei. Flow pattern and lubrication features in particulate lubrication interface [J]. China Mechanical Engineering, 2014, 25(19): 2562-2567.
WANG W, LIU Y, ZHU G Q. Using FEM-DEM coupling method to study three-body friction behavior [J]. Wear, 2014, 318(1/2): 114-123.
ELKHOLY K N, KHONSARI M M. Experimental investigation on the stick-slip phenomenon in granular collision lubrication [J]. Journal of Tribology, 2008, 130(2): 021302.
SUN Qicheng, WANG Guangqian. Force distribution in static granular matter in two dimensions [J]. Acta Physica Sinica, 2008, 57(8): 4667-4674.
SAZZAD M M, SUZUKI K, RAZAVI A M F. Macro-micro responses of granular materials under dif-ferent b values using DEM [J]. International Journal of Geomechanics, 2012, 12(3): 220-228.
CUNDALL P A, STRACK A. A discrete numerical model for granular assemblies [J]. Geotechnique, 1979, 29(1): 47-65.
CAO Miaoyan, DONG Guojiang, ZHAO Changcai. Research on pressure-transfer characteristics in the solid granule medium forming based on the discrete element method [J]. Journal of Mechanical Engineering, 2011, 47(14): 62-69.
GU X Q, YANG J, HUNAG M S. DEM simulations of the small strain stiffness of granular soils: effect of stress ratio [J]. Granular Matter, 2013, 15(3): 287-298.
CAMPBELL C S. Granular material flows-an overview [J]. Powder Technology, 2006, 162(3): 208-229.