This paper aims to analyze the effects of combined working coils magnetorheological (MR) absorber on shock mitigation performance and verify controllability MR as applied in recoil system a field gun. A physical scale model gun is established long-stroke with four-stage parallel electromagnetic designed apply separate current each stage generate variable magnetic distribution annular flow channel. Based dynamic analysis firing stability conditions gun, ideal force-stroke profiles at...

As a renewable energy resource, the pumped storage power station has great prospects for better balancing supply and demand, particularly with further development of intermittent sources growing need an intelligent electric grid. However, pump-turbines often involve problematic S-shaped regions in their machine characteristics thus, while may solve some problems grid, pump-turbine operation control can lead to other including severe self-excited oscillation hydro-mechanical system. These...

The article provides a novel method to control the amount of unbalance propagation in precise cylindrical components assembly, which takes machining error, measurement and assembly error into account. coefficient correction factor matrices mass eccentric deviations are defined analyze by building connective model. influence on center is analyzed assembly. cumulative deviation can be reduced stage final minimized controlling angle each component. effectiveness proposed verified real...

This investigation was attempted to introduce carbon nanotubes (CNTs) onto surface of copper powders in order improve heat transfer performance matrix for engineering application electrical packaging materials. The Ni/MgO catalyst formed on the by means codeposition method. CVD technique executed fabricate uniform CNTs and effect reaction temperature morphology surveyed. results showed that products powder were distributed uniformly even if different. diameter dimension within scope 30~60...

To address the poor electronic conductivity and easily dissolved in electrolyte of polyoxometalates (POMs), considering high electrical configuration advantages crumpled graphene balls (CGBs), herein, a series POM-based coordination polymers [Cu(pyttz)2 ]PMo12 @CGB (n, n=1, 2, 3) were successfully synthesized, electrochemical lithium storage performance ion diffusion kinetics comprehensively investigated. Galvanostatic intermittent titration technique (GITT) impedance spectroscopy (EIS)...

Purpose This paper aims to provide a precision assembly method improve the aircraft engine quality of initial unbalance with purpose founding process for mass eccentricity propagation and demonstration process. The proposed can be used guidance, tolerance allocation so on, especially large number rotors requirements coaxiality in high precision. Design/methodology/approach proposes constrained optimization-build minimize assembly, which takes amount concentricity each rotor into account. A...

Herein, the effects of addition TiB 2 –TiC nanoparticles on microstructure and tensile properties as‐cast gray cast irons are investigated. The in situ nanosized –TiC/Al master alloy is added casting process. It found that presence refines graphite flakes pearlite increases yield strength, fracture strain simultaneously. strengthening mechanisms related to grain refining Orowan strengthening. toughening mechanism scattering behavior cracks by nanoparticles.

In order to analyze the performance of lunar rover, draw bar pull and motion resistance are analyzed in this paper based on terramechanics. The relationships between configuration parameters (like wheel width, bases et al.) mobility obtained from analysis. Meanwhile, sensitive factors found. Then main evaluation metrics indexes presented, which comparison LER-1 ALR (a new rover) locomotion systems is performed. method evaluating rover by simulation introduced. analysis results indicate that...

In this paper, micrometers long and 20–100 nm diameter SiC nanowires had been synthesized in the short cut fiber toughened composites (Csf/SiC) by annealing treatment. The present work demonstrated that it was possible to fabricate situ Csf/SiC annealed "vapor–liquid–solid" growth mechanism of proposed. mainly concluded grain bridging, crack deflection, debonding nanowires, which can improve fracture toughness.

Offshore wind mill is the key factor for countries over world to use ocean resource and exploit economy, also one of our national important new energy development plans. farm construction started late in country, offshore power technology need be improved practice. Due difference on distance, installed capacity, marine condition, investment capacity other conditions, selection submarine cables presented a variety ways. According typical domestic farm, China has successfully developed 220 kV...

In the operation of pumped storage plant, sudden change load in large range often happen, design reversible pump-turbine emergency closing law should satisfy limit rotation speed-rise and pressure-rise. The broken-line usually used plants is discussed based on full hydraulic characteristic pump-turbine, three stages with delayed segment designed, virtues defects are also analyzed. Numerical calculation field test indicate that water hammer plant conveyance system caused by wicket gate...

In view of the surface engineering application electrical contact materials, SiC ceramic particles were introduced into copper matrix composites by hot-press sintering method for sake enhancing service life materials. Magnetron sputtering technology was exploited to form continuous film on β-SiC powders in order improve interface wettability between powder and matrix. The SiC@Cu treated magnetron technology. Then, dynamic deposit behavior described according SEM results. phase constitution,...

For a hydropower station with longer water conveyance system, an optimum turbine's selection will be beneficial to its reliable and stable operation. Different optional turbines result in possible differences of the hydraulic characteristics hydromechanical have different effects on transients' analysis control. Therefore, premise for is fully understand properties their transients. After brief introduction simulation models computation stability analysis, at operating points...