scholarly journals Dynamic method of stiffness identification in impacting systems for percussive drilling applications

2016 ◽  
Vol 80 ◽  
pp. 224-244 ◽  
Author(s):  
Maolin Liao ◽  
James Ing ◽  
Mukthar Sayah ◽  
Marian Wiercigroch
Keyword(s):  
Dynamic Method ◽  
Percussive Drilling ◽  
Stiffness Identification ◽  
Impacting Systems

Selectivity coefficients of some simple and complex inorganic ions for Spheron DEAE

1984 ◽  
Vol 49 (10) ◽  
pp. 2349-2354 ◽  
Author(s):  
František Vláčil ◽  
Karel Koňák
Keyword(s):  
Ion Exchange ◽  
Mobile Phase ◽  
Dynamic Method ◽  
Precious Metals ◽  
Inorganic Ions ◽  
Chromatographic Determination ◽  
Chloride Ions ◽  
Chloro Complexes ◽  
Selectivity Coefficients

The selectivity coefficients of the nitrate and chloride ions and of anionic chloro complexes of Au(III), Rh(III), Pd(II), and Pt(IV) for ion exchange on Spheron DEAE in the chloride form are determined by the dynamic method. the complex anion species formed are identified and the ion exchange nature of the sorption of precious metals on this sorbent is confirmed based on the elution order of the precious metals as determined previously by the column chromatography on Spheron DEAE using hydrochloric acid as the mobile phase. The effect of the presence of perchlorate in the mobile phase during the liquid chromatography of precious metals and during the chromatographic determination of nitrate traces is explained.

Extra-Column Effects in Determination of Rate Parameters by the Chromatographic Method

1996 ◽  
Vol 61 (6) ◽  
pp. 844-855 ◽  
Author(s):  
Olga Šolcová ◽  
Petr Schneider
Keyword(s):  
Chromatographic Method ◽  
Dynamic Method ◽  
Axial Dispersion ◽  
Transport Parameters ◽  
Porous Particles ◽  
Loop Detector ◽  
Single Pellet ◽  
Set Up ◽  
Extra Column Effects

It was shown that the sampling loop, detector and connecting elements in the chromatographic set-up for determination of transport parameters by the dynamic method significantly influence the response peaks from columns packed with porous or nonporous particles. A method, based on the use of convolution theorem, was developed which can take these effects into account. The applicability of this method was demonstrated on the case of axial dispersion in a single-pellet-string column (SPSR) packed with nonporous particles. It is possible to handle also responses from columns packed with porous particles by a similar procedure.

scholarly journals Pool Boiling Heat Transfer Coefficients in Mixtures of Water and Glycerin

Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 830
Author(s):  
Viktor Vajc ◽  
Radek Šulc ◽  
Martin Dostál
Keyword(s):  
Heat Transfer ◽  
Dynamic Method ◽  
Water Mass ◽  
Heat Fluxes ◽  
Static Method ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
Mean Relative Error ◽  
Mixture Effects ◽  
Mass Fractions

Heat transfer coefficients were investigated for saturated nucleate pool boiling of binary mixtures of water and glycerin at atmospheric pressure in a wide range of concentrations and heat fluxes. Mixtures with water mass fractions from 100% to 40% were boiled on a horizontal flat copper surface at heat fluxes from about 25 up to 270kWm−2. Experiments were carried out by static and dynamic method of measurement. Results of the static method show that the impact of mixture effects on heat transfer coefficient cannot be neglected and ideal heat transfer coefficient has to be corrected for all investigated concentrations and heat fluxes. Experimental data are correlated with the empirical correlation α=0.59q0.714+0.130ωw with mean relative error of 6%. Taking mixture effects into account, data are also successfully correlated with the combination of Stephan and Abdelsalam (1980) and Schlünder (1982) correlations with mean relative error of about 15%. Recommended coefficients of Schlünder correlation C0=1 and βL=2×10−4ms−1 were found to be acceptable for all investigated mixtures. The dynamic method was developed for fast measurement of heat transfer coefficients at continuous change of composition of boiling mixture. The dynamic method was tested for water–glycerin mixtures with water mass fractions from 70% down to 35%. Results of the dynamic method were found to be comparable with the static method. For water–glycerin mixtures with higher water mass fractions, precise temperature measurements are needed.

scholarly journals Simulation on compound percussive drilling: Estimation based on multidimensional impact cutting with a single cutter

2021 ◽  
Vol 7 ◽  
pp. 3833-3843
Author(s):  
Yumei Li ◽  
Tao Zhang ◽  
Zefang Tian ◽  
Yiming Zheng ◽  
Zengmin Yang
Keyword(s):  
Percussive Drilling ◽  
Impact Cutting

Numerical simulation of impact on pneumatic DTH hammer percussive drilling

2009 ◽  
Vol 20 (5) ◽  
pp. 868-878 ◽  
Author(s):  
Changgen Bu ◽  
Yegao Qu ◽  
Zhiqiang Cheng ◽  
Baolin Liu
Keyword(s):  
Numerical Simulation ◽  
Percussive Drilling

Safety Analysis of Static & Dynamic Method in Foundation Pit Considering Unsaturated Seepage

2013 ◽  
Vol 444-445 ◽  
pp. 946-950
Author(s):  
Yi Hong Zhou ◽  
Xiu Wen Li ◽  
Yun Feng Peng ◽  
Ting Zhang
Keyword(s):  
Slope Stability ◽  
Dynamic Analysis ◽  
Unsaturated Zone ◽  
Dynamic Method ◽  
Soil Consolidation ◽  
Main Study ◽  
Dynamic Boundary Conditions ◽  
Foundation Pit ◽  
Consolidation Settlement ◽  
Unsaturated Seepage

In order to study whether foundation pit is stable or not after excavation, the article adopted the Duncan E-B model to make static analysis for the excavation scheme which considering the soil consolidation settlement and to make dynamic analysis under the action of earthquake wave of EL Centro. To make a slope stability of foundation pit analysis by calculating static and dynamic boundary conditions which further coupled with the Newmark method. The main study is the foundation settlement and earth-rock dams, slope stability of foundation pit conditions that considering unsaturated zone seepage conditions of earth-rock dams after the excavation. The results indicated that: in the static & dynamic analysis, the distribution about settlement is reasonable, earth-rock dam and foundation pit slope is in the steady state, the excavation scheme is reasonable and feasible.

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