TORQUE CAPACITY AND CONTACT EFFICIENCY OF A HALF TOROIDAL CONTINUOUSLY VARIABLE TRANSMISSIONS

The automotive industry is seeking new concepts for a continuously variabletransmission (CVT) in the driveline. One possible solution for a CVT design is half toroidaltraction drive, providing a high torque capacity with quick ratio change. An analytical study on thecontact points of the half toroidal CVT has been detailed. The shapes of the contact areas amongthe input disk, power roller and output disk are considered ellipses. Mathematical equations forestimating the torque capacity, power loss due to spin action, and contact efficiency of theelliptical contacts of the half toroidal CVT are formulated and expressed in the form of integralswhich can be readily evaluated by numerical scheme. The contact efficiency calculations of the halftoroidal CVT have been developed for the proper spin point locations under the effect of systemparameters. Numerical results are presented hi graphical forms for considered parameters, which canhelp the designer to select the proper system parameters to minimize the undesirable spin effects.

Flow dynamics and contact efficiency in a novel fast-turbulent fluidized bed with ring-feeder internals

The flow dynamics in a novel fast-turbulent fluidized bed （FTFB） with middle-upper expanding structure and two different ring-feeder internals （mixed and vortex ring-feeder） were studied to achieve a reduction in gasoline olefin production, Compared with a conventional circulating fluidized bed, the novel FTFB displayed unique characteristics and advantages. A higher solids holdup and more uniform solids holdup distribution existed in the diameter-expanding region, especially for the FTFB with vortex ring-feeder structure, A probability density distribution analysis indicated that the novel fluidized bed could reduce gas-solids segregation and enhance gas-solids interaction. A constant carbon dioxide tracer system was used to simulate the reactant gas distribution. The gas-solids contact efficiency was defined according to the solid dispersibility and the amount of gas covering the solid surface. Novel FTFB risers, especially those with vortex ring-feeders, have a much higher gas-solids contact efficiency than that of traditional risers.

Facile preparation and efficient MnxCoy porous nanosheets for the sustainable catalytic process of soot

The pursuit of high-performance is worth considerable effort in catalysis for energy efficiency and environmental sustainability. To develop redox catalysts with superior performance for soot combustion, a series of Mn_(x)Co_(y) oxides were synthesized using MgO template substitution.This method greatly improves the preparation and catalytic efficiency and is more in line with the current theme of green catalysts and sustainable development. The resulting Mn_(1)Co_(2.3) has a strong activation capability of gaseous oxygen due to a high concentration of Co^(3+) and Mn^(3+). The Mn doping enhanced the intrinsic activity by prompting oxygen vacancy formation and gaseous oxygen adsorption. The nanosheet morphology with abundant mesoporous significantly increased the solid–solid contact efficiency and improved the adsorption capability of gaseous reactants. The novel design of Mn_(1)Co_(2.3)oxide enhanced its catalytic performance through a synergistic effect of Mn doping and the porous nanosheet morphology, showing significant potential for the preparation of high-performance soot combustion catalysts.

Influence of Structure Parameters on Performance of the Thermoelectric Module

A numerical model of thermoelectric module （TEM） is created by academic analysis,and the impacts of the resistance ratio and thermoelement size on the output power and thermoelectric efficiency of the TEM are analyzed by the MATLAB numerical calculation.The numerical model is validated by the ANSYS thermal,electrical,and structural coupling simulation.The effects of the variable physical property parameters and contact effect on the output power and thermoelectric efficiency are evaluated,and the concept of aspect ratio optimal domain is proposed,which provides a new design approach for the TEM.

Constructing robust all-inorganic contacts enable stable perovskite solar cells with efficiencies over 20%

Developing photovoltaic(PV)cells for harvesting renewable and clean solar energy is a promising strategy to meet the growing energy demand.Perovskite solar cells(PSCs),as a new player in the photovoltaic field,exhibit rapid development with an original power conversion efficiency(PCE)of 3.81%in 2009,a promising PCE of over 20%in 2014 and a record PCE of 22.1%in

Experimental study on reactor performance of gas-solids low-velocity fluidized beds

Reactor performance of bubbling fluidized bed(BFB)and turbulent fluidized bed(TFB)was carefully examined and systematically compared using catalytic ozone decomposition as a model reaction,based on a complete mapping of local flow structures and spatial distributions of ozone conversion and solids holdup.TFB clearly has a higher conversion and shows better reactor performance than BFB as a result of the vigorously turbulent flow and the relatively homogeneous gas–solids mixing in TEB.Besides,the intensive interaction between gas and solids in TFB leads to greater gas–solids contact efficiency of TFB over that of BFB.Due to gas bypassing and backmixing caused by bubbling behaviours and two-phase structure,BFB deviates significantly from a plug flow reactor and sometimes from a continuously stirred tank reactor.The flow structures essentially dictate the reactor performance in the low-velocity fluidized beds.