The possibility of applying a high-pressure hydro-jet for renewal of the grinding wheel cutting ability was presented.This work was conducted in the internal cylindrical grinding process of the Titanium Grade 2 alloy,...The possibility of applying a high-pressure hydro-jet for renewal of the grinding wheel cutting ability was presented.This work was conducted in the internal cylindrical grinding process of the Titanium Grade 2 alloy,which belongs to the group of hard-to-cut materials.The analysis shows that the impact on the erosion effectiveness of the grinding wheel active surface(GWAS)depends upon the hydro-jet inclination angle and working pressure.Experimental results reveal that application of hydro-jet working pressure of 25 MPa allows for effective cleansing of the grinding wheel surface.Depending on the initial GWAS condition and the level of its smearing with chips of machined material,it is possible to increase the number of grinding wheel unevenness apexes by as much as 4.5 times.展开更多
Experimental investigation was conducted to investigate the impingement heat transfer performance of a synthetic jet driven by piston actuator on a constant heat flux surface. Effects of jet formation frequency, nozzl...Experimental investigation was conducted to investigate the impingement heat transfer performance of a synthetic jet driven by piston actuator on a constant heat flux surface. Effects of jet formation frequency, nozzle-to-surface spacing ratio and con- jugation of cross flow were considered. The synthetic jet is of stronger penetration and heat transfer capacity when the piston reciprocates at relatively high frequency. Similar to the continuous jet impingement, nozzle-to-surface spacing ratio plays an important role in the heat transfer enhancement of synthetic jet. The optimum nozzle-to-surface spacing ratio corresponding to maximum heat transfer enhancement is considerably high in the synthetic jet, as compared to that in a continuous jet, which indicates that the synthetic jet introduces a stronger entrainment and more vigorous penetration in the surrounding fluid. The convective heat transfer capacity is enhanced significantly under the conjugate action of a synthetic jet and cross flow in com- narison with their individual action.展开更多
文摘The possibility of applying a high-pressure hydro-jet for renewal of the grinding wheel cutting ability was presented.This work was conducted in the internal cylindrical grinding process of the Titanium Grade 2 alloy,which belongs to the group of hard-to-cut materials.The analysis shows that the impact on the erosion effectiveness of the grinding wheel active surface(GWAS)depends upon the hydro-jet inclination angle and working pressure.Experimental results reveal that application of hydro-jet working pressure of 25 MPa allows for effective cleansing of the grinding wheel surface.Depending on the initial GWAS condition and the level of its smearing with chips of machined material,it is possible to increase the number of grinding wheel unevenness apexes by as much as 4.5 times.
基金supported by the National Natural Science Foundation of China (Grant Nos. 50276028,51106073)
文摘Experimental investigation was conducted to investigate the impingement heat transfer performance of a synthetic jet driven by piston actuator on a constant heat flux surface. Effects of jet formation frequency, nozzle-to-surface spacing ratio and con- jugation of cross flow were considered. The synthetic jet is of stronger penetration and heat transfer capacity when the piston reciprocates at relatively high frequency. Similar to the continuous jet impingement, nozzle-to-surface spacing ratio plays an important role in the heat transfer enhancement of synthetic jet. The optimum nozzle-to-surface spacing ratio corresponding to maximum heat transfer enhancement is considerably high in the synthetic jet, as compared to that in a continuous jet, which indicates that the synthetic jet introduces a stronger entrainment and more vigorous penetration in the surrounding fluid. The convective heat transfer capacity is enhanced significantly under the conjugate action of a synthetic jet and cross flow in com- narison with their individual action.