Search Documents

THE THIRD INTERNATIONAL GEOCHEMICAL EXPLORATION SYMPOSIUM (Summary Account) This Symposium, co-sponsored by the Canadian Institute of Mining and Metallurgy and the Society of Economic Geologists, was held in Toronto, Canada in April, 1970. Over 700 delegates attended from 26 countries. Ninety papers were presented at the symposium and another 18 papers were read by title. The programme included: An Opening Session, Five General Sessions, a session on Remote Sensing Methods, a session on Geochemical Prospecting for Petroleum and Natural Gas, a session on Primary Halos and Lithogeochemical Methods, and a session on Statistics and Evaluation of Geochemical Data. The delegates were welcomed by Dr J. M. Harrison, President of the Canadian Institute of Mining and Metallurgy and Dr C. H. Smith, Regional Vice-President, North America of the Society of Economic Geologists. Dr D. R. Derry of Toronto delivered the opening address to the Symposium entitled 'Geochemistry-the link between ore genesis and exploration'. Dr Derry considered the various hypotheses on the origin of economic mineral deposits and expressed his belief that the next ten years will show evidence of an increased proportion of ore bodies that owe their origin, at some stage in time, to supergene agencies. He stressed that 'there are no sharp divisions between processes that form and destroy ore bodies at or near surface and those that form or destroy them at a depth of 20 kilometres in the earth's crust. The more we understand about the migration and concentration of metals the more accurately we can apply this knowledge to searching for unknown concentrations, whether at rock surface or at depth. To learn more about these processes of ore genesis we must rely on geochemical studies co-ordinated with field observations'. The five general sessions included accounts of progress in geochemical prospecting in different countries of the world, case histories describing the application of soil, stream sediment, geobotanical and biogeochemical techniques, papers on the behaviour of different elements under varied environmental conditions, discussions on analytical methods and the use of stable isotopes in mineral exploration. It is anticipated that the proceedings of the Symposium will be published late in 1970 or early in 1971 as a Special Volume of The Canadian Institute of Mining and Metallurgy. All registrants at the Symposium will receive a copy of this publication and copies will be available for purchase. At a special meeting called during the Symposium, charter members of the Association of Exploration Geochemists approved a constitution and elected an interim Council which will organize procedure and formulate policy during the coming year. The interim president of the Association is J. Alan Coope, Newmont Mining Corporation of Canada Limited, Toronto, Canada. More information on the constitution and membership in the Association will be distributed to learned societies and technical magazines in the near future. Membership will be open to exploration geochemists in all countries of the world. SOUTH AFRICAN COUNCIL FOR PROFESSIONAL ENGINEERS Report on Registration The Professional Engineers Act (Act 81 of 1968) came into force on the 14th February, 1969. At the time it was recognised that the success of the Act would depend in large measure on the extent to which engineers in South Africa would become registered professional engineers in terms of the provisions of the Act. The promulgation of the Act and its provisions relevant to registration were the subject of considerable publicity during 1969. This has resulted in a rate of application for registration far beyond the capacity of the very active committees set up for this purpose by the South African Council for Professional Engineers (SACPE). To give some idea of the task before these committees and before SACPE itself, which must ratify each case,

By I. O. Flores, A. Anani, H. Li

Current technological advancement has increased the exploitation of deeper ore bodies using underground methods. In certain cases, the mineral deposit starts near the surface and continues deep within the earth's crust. Such deposits are best mined with both underground and surface methods. Two main techniques are used to determine the optimal transition depth from surface to underground - a disintegrated approach and an integrated approach. Both methods have limitations in their use to determine the optimal transition depth. The objective of this research is to investigate the conditions in which an integrated approach to the transition depth problem is superior to a disintegrated approach. Three binary integer linear programming models are developed for this purpose: a surface and underground model for the disintegrated instance and an integrated model. A case study is performed to validate the models, with a comparative sensitivity analysis to obtain operational insights.

Sep 1, 2021

By J. Hadjigeorgiou, Y. Potvin

In a benchmarking paper published in the SAIMM Journal, Potvin and Hadjigeorgiou (2008) reviewed ground control strategies to manage large deformations in underground hard rock mines. Significant differences were identified in the design and acceptable tolerance between civil and mining engineering practice for squeezing ground conditions. Variations were also noted in ground support strategies between Australian and Canadian mines. In this paper we review progress in design methodology and ground support practice since 2008, including the availability of more effective deformation monitoring, new design tools, greater access to yielding ground support elements, and better installation practices. An improved understanding of technical and practical issues associated with squeezing conditions has led to the development of ground support guidelines for a range of squeezing ground conditions in hard rock mines.

Jul 5, 2023

By P. J. Le Roux

"Mining companies are under constant pressure to reduce their cost structures to sustain profitability. In mines using an open stoping mining method, dilution often has a significant effect on profitability. At Target mine in South Africa, dilution in some open stopes was found to exceed 10%, falls of ground being a major contributor to the problem. This dilution can reduce the recovered grade from 5.5 to 4.5 g/t, resulting in a potential loss of about R21 million per month based on a gold price of R240 000 per kilogram. In addition to the cost of dilution, the cost of damage to, or loss of, trackless equipment as a direct result of falls of ground in open stopes is significant. Other associated costs include transport, hoisting, secondary blasting, milling, and plant treatment of waste material. Stable open stopes are essential in order to reduce falls of ground. Back-analyses of stope instability at Target mine have indicated that conventional rock mass failure criteria are unsuitable for stope design. An alternative strain-based criterion has been developed, and has proved to be very successful, allowing the stability of open stopes to be calculated reliably. Since its implementation in 2010, dilution and equipment damage have decreased markedly, creating value for the mine. IntroductionMines that make use of an open stoping mining method aim to extract only the ore, leaving the waste behind. Many orebodies have well-defined boundaries between the ore and the waste rock. In such orebodies, the introduction of waste into the ore due to overbreak dilutes the grade. In massive disseminated orebodies, dilution is less problematic. Overblasting, falls of ground, or other causes may result in dilution. A study undertaken in Canada (Pakalnis et al., 1995) found that approximately 51% of all underground metal mines utilized open stoping mining methods and, from surveys conducted at these mines, open stoping operations experienced dilutions of up to 20%, and occasionally more. Dilution of this magnitude has a significant economic impact on any mining venture. Research carried out in Australia by Capes (2009) came to the same conclusion."

Jan 1, 2017

By A. P. L. Kotzé

Modelling and scheduling for Grootegeluk coal mine, situated in the north- western Transvaal, is by means of a series of modular systems. Modelling of the multilayered body, which is part of the Waterberg coalfield, was based on a detailed study of the behaviour of coal and waste qualities and the sub- sequent use of standard geostatistical techniques. A notable improvement on previous methods was attained. Scheduling procedures and systems were developed to model a multibench pit producing coal for several metallurgical plants as well as a power-station. Scheduling was done by producing a series of longitudinal cuts, the cuts being subdivided into increments. By allocating cuts to certain periods, the resulting calculated product tonnages were com- pared with production targets, and by iteration a final scheduling sequence was determined.

Jan 1, 1987

By Z. Leng

"After detonation of the explosive, the final blast-induced damage area around the blast-hole falls into three categories, namely crushed zone, fractured zone, and elastic deformation zone. This paper presents a modified model to calculate the size of crushed zone around a blast-hole in drill-and-blast, with the hoop compressive stress and cavity expansion effect taken into account. The material in the crushed zone was assumed to be a granular medium without cohesion, but with internal friction. On this basis, the formula for crushing zone radius was derived. The proposed approach was verified with tests reported in the literature and the simulated results from SPH-FEM coupled models. A full statistical analysis was also carried out, and the predicted values were found to be in better agreement with the test results compared with other models. A sensitivity analysis of the modified model showed that the size of the blast-induced damage area is mainly affected by the following factors: rock mass properties, in situ stress, and borehole pressure. In particular, the roles of borehole pressure and in situ stress are discussed. Finally, suggestions are made on how the size of the crushing zones can be decreased. IntroductionOver the past decades, drill-and-blast has become the most commonly used technology in rock excavation. It is well known that in rock mass fragmentation with explosives, the annular rocks around the blast-hole are converted into fines. The formation of these fines consumes a significant part of the energy of the detonation, which in general is ignored in the determination of the efficiency of detonation (Glatolenkov and Ivanov, 1992; Furtney et al., 2012). Many studies show that only 20–30% of the total explosive energy is effectively used in fragmenting the rock, and up to 50% of the energy generated by conventional charges is wasted in overcrushing of the crushed zone and the inner part of the fractured zone (Ouchterlony et al., 2004; Sanchidrian et al., 2007). How to control the crushed zone to enhance the effective utilization of explosive energy, reducing the unit explosive consumption and the engineering cost, is therefore of great significance."

Jan 1, 2016

Slope stability is a fundamental part of a successful mining operation. It impacts directly on the safety of personnel and the economics of the mine. The Jwaneng Mine in Botswana is planning a push back of 644m depth in the south east wall. Mining will commence in 2010 and be completed in 2024. This will put the mine in the deep pit category. The mine has invested in extensive geotechnical data gathering and design programs that started as far back as 2003 for the south east wall. The south east wail of Jwaneng Mine is characterized by foliation that dips adversely into the mining faces. The orienta1ion of the foliation is variable due to intense tectonic movements that have also caused the occurrence of faults that are sub-vertical. A considerable amount of information on the characteristics of structural patterns and the rock mass has been collected. This paper presents an overview of the feasibility level geotechnical design that is about to be concluded.

Jan 1, 2010

By K. J. Craig, M. A. Swart, Q. G. Reynolds, L. Hockaday

A solar reflector soiling study was carried out at a ferromanganese smelter in South Africa to assess the soiling rates at different locations around the plant. Several meteorological parameters were monitored to give insight into the conditions that lead to increased soiling. Mineralogical characterization of dust samples collected from the reflectors and the atmosphere revealed that only a certain size fraction is of importance with regard to soiling, and that the dust can be attributed to both raw materials and smelter products. Proximity to the dust source was the primary driver for increased soiling. The site that experienced the most soiling was very close to raw material heaps; this was deemed an outlier and was excluded from the summary statistics. The secondary driver for increased soiling was location relative to the smelter dust sources and the wind’s direction and speed. The reflector set at the best location experienced 13.1% less soiling than the set at the ‘worst’ (but still feasible) location, represented by an averaged mean daily reflectance loss of 0.0186. The study revealed that while there are periods of intense soiling at this particular site, proper planning of reflector location in relation to the smelter dust sources can significantly mitigate the soiling rate.

Jun 5, 2023

By Y. J. Cao

The purpose of this study was to investigate the flotation behaviour of unburned carbon in a cyclonic-static microbubble flotation column (FCSMC). The ash sample, collected from a power station in Guangdong province of China, was characterized by size analysis, X-ray diffraction, contact angle measurements, and X-ray fluorescence. The effect of the column flotation operating variables on the removal of unburned carbon from the fly ash was systematically studied. The feasibility of separating unburned carbon and ash was determined from the removal rate of unburned carbon (RUC) and loss on ignition (LOI). Within the range studied, the optimum diesel oil dosage was 1200 g/t, abies oil dosage was 600 g/t, pulp density was 20 per cent, superficial gas velocity was 1.4 cm/s, and circulating pressure was 0.20 MPa. The results indicate that the FCSMC technique is effective in removing the unburned carbon from the fly ash, which can be attributed to the generation of microbubbles and the continuous cyclonic circulation method. Under the optimized conditions, a cleaning ash with 2.13 per cent LOI and 94.21 per cent RUC was obtained.

Jan 1, 2012

By J. Petersen, T. Moyo, J. Dinga

The leaching of chalcopyrite in ferric sulfate media is notorious for its slow and inhibited kinetics. Different methods have been proposed to improve the kinetics, including the use of organic compounds as additives to the leaching media. In this study, the enhancing effect of methanol, ethanol, 1-propanol, and 2-propanol on the leaching of chalcopyrite in aerated acid ferric sulfate solutions using different reactor systems was investigated. The results revealed a clear improvement of copper dissolution by methanol and 1-propanol relative to tests with no additives under similar conditions. Operating a continuous-flow mini-column reactor yields surprisingly good results, potentially related to the maintaining of a consistent leaching micro-environment on the mineral surface. Scanning electron microscopy studies showed that the alcohols result in the removal of surface deposits formed during the anodic dissolution, potentially thus facilitating improved cathodic reduction of the ferric ion to drive the anodic dissolution.

Jan 1, 2023

By H. Han, Z. Gao, Y. Gao, W. Sun, J. Wang

Strategic Ca-bearing minerals like scheelite and fluorite are usually separated by flotation, yet the separation is quite difficult due to their similar surface Ca active sites. Compared with the conventional strong collector sodium oleate (NaOL), lead nitrate-benzohydroxamic acid (Pb-BHA), complex collector shows a better selectivity for scheelite, yet its high cost hinders its wide application. Therefore, a novel collector (Pb-BHA-NaOL complex) was initially developed in this work to overcome the abovementioned dilemma. The flotation results of a single mineral showed that Pb-BHA-NaOL had a better selectivity for scheelite than Pb-BHA. Under the conditions of sequential assembly of Pb, BHA and NaOL at the molar ratio of 240:120:1 and pH 9.0, selective separation of scheelite from fluorite could be achieved without adding any depressants. In addition, for the same preferred scheelite recovery, Pb- BHA-NaOL could also save approximately 20% Pb and BHA compared with Pb-BHA. The analyses of the zeta potential measurement and X-ray photoelectron spectroscopy indicated that Pb-BHA-NaOL showed stronger adsorption on scheelite relative to fluorite. Meanwhile, Pb-BHA-NaOL showed more adsorption modes and higher utilisation of Pb and BHA on scheelite than Pb-BHA, which was due to the accelerator, NaOL. Keywords: Scheelite, fluorite, lead nitrate, benzohydroxamic acid, sodium oleate, flotation

Jan 1, 2020

By A. Y. Senchenkoa, Y. V. Kulikov

The relationships revealed between ore hardness and specific energy consumed by crushing and grinding are described in the paper. A comparison of key technical and economical parameters of SAG and HPGR circuits is made, based on testing of several ore types for greenfield projects. The comparison of results make it possible to estimate efficiency of the technologies application, depending on ore hardness and taking into account potential risks for a circuit under design. Keywords: Comminution circuits, SAG, HPGR, test results

Jan 1, 2020

By A. Yañez, J. Yianatos, P. Vallejos, R. Grau

This paper presents an evaluation of the effect that the mineral feed characteristics have on the metallurgical performance in an industrial flotation circuit. Variables such as mineralogy, particle size, solid content and mineral grade were evaluated using a flotation simulator, which was previously developed and validated using industrial data from different concentrators. The metallurgical performance was evaluated not only from the point of view of recovery and concentrate grade, but also by analysing less common variables such as froth carrying rate, froth and collection recovery, water recovery and others. Then, new data from the industrial flotation circuit was used to complement this analysis and evaluate the simulator predictability by comparing simulated and measured data. The results allowed for the quantification of the significant effect that mineralogy and particle size have on recovery and/or concentrate grade. Therefore, the grinding stage and flotation cells design become important factors to avoid a significant loss in metallurgical performance when feed mineral characteristics change in an industrial operation. In this context, an evaluation of cells design and arrangement should be performed to compensate the loss in recovery and concentrate grade in order to find an optimal operating condition. Keywords: Flotation circuits, mineral feed, modelling, particle size, liberation, mineralogy

Jan 1, 2020

By and Z. S. Abisheva, Z. B. Karshigina, Ye. G. Bochevskay, A. S. Sharipova

The production of precipitated silica in the United States is about 145,000 tons of SiO2 and its prices vary significantly (from $ 1 to $ 4.5 per kg) depending on the area of its application. One of the most important parameters is its specific surface characterising dispersion (particle size and shape, presence or absence of pores), at a certain value of which the material acquires new properties and quality. At present, a technology has been developed for processing slag from phosphorus production to produce precipitated silica (‘white soot’) with a high specific surface and the possibility of extracting valuable components such as rare-earth metals (REMs) into a product enriched with them has been shown. However, the content of impurities in the deposited silicon dioxide, such as aluminum and iron, is above acceptable limits and may affect the quality of the final products. Therefore, along with the structure and specific surface, a very important characteristic of ‘white soot’ is the chemical purity of the material. In turn, calcium oxide occupies a significant share in the concentrate of rare-earth metals, which affects the content of ΣREMs oxides, which does not exceed 17.3 %. The low content of a valuable component may affect the feasibility of further processing. For the most complete utilisation of phosphorus slag, the authors propose a method for their acid processing, which allows for minimising the conversion of impurities to finely divided silica and collective concentrate, which will improve the quality of these products. Keywords: Phosphorus slag, precipitated silicon dioxide, rare earth metals, leaching, white soot, specific surface, technology

Jan 1, 2020

By D. J. Briggs

The use of backfill for regional and local support is receiving increasing attention in the South African mining industry. To ensure that fill materials meet the purposes for which they are intended, a test procedure to characterize the load-deformation characteristics for a particular fill was developed. The major variables identified as influencing the load-bearing proper- ties of backfill include particle size distribution, porosity, width-to-height ratio, strain rate, confinement, water content, and additives. The influence of these variables on the performance of backfill is described in relation to crushed waste, dewatered tailings and deslimed tailings. These investigations confirmed that no single test could be used to define the overall stress-strain behaviour of a selected fill. Nevertheless, resulting from this work, a preliminary standard test procedure for uncemented backfill materials, com- prising a suite of tests in unconfined and confined compression, has been formulated. This test procedure is a significant advance towards a more meaningful evaluation of fill materials. Test results will also provide numerical information for input use in computer programs for the design of mine layouts incorporating backfill.

Jan 1, 1988

By K. B. Le Bron, T. van Aard

The empirical pillar strength formulae have been widely, and in most cases successfully, applied to design underground pillars for mines in the Bushveld Igneous Complex (BIC). This paper presents the case for combining the empirical method with numerical modelling when it comes to crush pillar stability analyses. The benefits include an understanding of potential failure mechanisms, which may then be accounted for in the designs. In addition, the impact of weak layers, such as shear zones, the impact of the dip of the orebody, differences in layouts, such as holing widths and the presence of advanced strike gulleys (ASGs) immediately adjacent to the crush pillars, and stress regime (k-ratio) may be studied using numerical modelling, as it is not accounted for in the empirical method.

Mar 5, 2025

By U. Atici, R. Comakli

"Understanding rock properties is of vital importance in mining and civil engineering. Rock properties are generally determined through laboratory tests, which require a large number of uniformly shaped samples and technicians who use indirect methods to determine rock properties. The texture coefficient (TC), which represents various textural parameters including the size, shape, orientation, and relative proportions of grains and the matrix, is an efficient means for indirectly evaluating the mechanical behaviour of rocks. In this study, 12 different rocks (ten granites, one diorite, and one gabbro) were collected and their engineering properties. including specific gravity, porosity, P- and S-wave velocities, Schmidt rebound hardness, uniaxial compressive strength, and elasticity modulus, were investigated. Relationships between TC and these measured properties were assessed. Statistically significant (at the 95% confidence level) correlations were found between the TC and compressive strength, elasticity modulus, sound velocity (both compression and shear waves for dry and saturated samples), but no significant correlation was found with Schmidt rebound hardness. The results suggest that it is possible to use the relationships between TC and the mechanical properties of rocks in rock classification. IntroductionIn every aspect of rock engineering, knowing rock properties is essential for determining and predicting the behaviour of rocks and rock masses. Mechanical properties of rocks are important parameters in mining, geology, and engineering, and they are affected by textural characteristics such as grain size, grain shape, cement type, degree of cementation, mineral content, and the ratio of the grain area to the matrix area. The effects of textural properties on the physical and mechanical properties of rocks have been investigated for a long time, and previous studies revealed close relationships between single parameters related to rock texture and mechanical properties of rocks (Akesson et al. 2001; Gunsallus and Kulhawy 1984; Merriam, Rieke, and Kim, 1970: Onodera and Kumara 1980; Prikryl 2006; Ulusay, Tureli, and Bider, 1994; Tugrul and Zarif 1998). Rock properties are usually determined using mechanical tests, which require uniformly shaped and relatively large samples. However, it is not always possible to obtain such samples. Furthermore, rocks with similar textural and structural properties may exhibit different mechanical behaviour. Howarth and Rowlands (1987) developed a texture coefficient (TC) that expresses all the main textural parameters of a rock in a single dimensionless quantity based primarily on statistical assessment. The TC makes it possible to understand the effects of a rock’s textural properties on its mechanical properties using thin sections instead of large, uniform samples. Ersoy and Waller (1995) investigated the relationship between strength and TC for limestone, sandstone, and siltstone; they also examined the effect of rock properties and TC on drilling performance. Ozturk, Nasuf, and Bilgin (2004) explored the relationship between rock quality and TC by evaluating the uniaxial compressive strength (UCS) values of limestone, basaltic andesite, and tuff. Gupta and Sharma (2012) evaluated TCs as well as the petrophysical and mechanical properties of quartzite from the lower and higher Himalayas and found a strong relationship between TC and UCS. Similarly, Ozcelik, Bayram, and Yasitli (2013) investigated the relationship between TC and various parameters in marble by applying the statistical analyses developed by Ozturk, Nasuf, and Kahraman (2014)."

Jan 1, 2019

Mr G. Maude was educated at Huish's Grammar School (Taunton) and Leeds University. He graduated in 1961 with a B.Sc. degree in Mining. Mr E.B. Crocker was educated at Florida Park High School, Witwatersrand Technical College, and the University of the Witwatersrand.

Jan 1, 1985

By A. Tosun

"The size distribution of the muckpile formed as a result of open pit blasting operations has a considerable effect on the efficiency of loading, hauling, and crushing. Various researchers have developed specialized computer software that uses image analysis methods for determining the size distribution of the muckpile. However, these methods have some limitations. One of the most important of these limitations is that the very fine fragments in the muckpile cannot be used in the size distribution calculation. In this study, 18 test blasts in total were carried out in two limestone quarries belonging to Batiçim Corp. in Izmir, Turkey. A new model was developed in order to ensure that very fine fragments are used in the size distribution calculation. The size distributions of the test blasts were calculated by both the Wipfrag computer program and the new model. Correlations were established between the muckpile size distributions determined by both methods and the parameters determining the efficiency of the loader. IntroductionThe size distribution of the muckpile formed as a result of open pit blasting operations has a considerable effect on the efficiency of loading, hauling, and crushing. Various researchers have established certain correlations for predicting the efficiency of the operations according to the muckpile size distribution so that production can be carried out economically (Tunstall and Bearman, 1997; Nielsen and Kristiansen, 1996; Workman and Eloranta, 2004; Michaud and Blanchet, 1996; Frimpong, Kabongo, and Davies, 1996; Osanloo and Hekmat, 2005; Molotilov et al., 2010). In these studies, the 50% passing size (X50) is generally used. These methods rely on the correct measurement of the size distribution of the muckpile formed by the blast. The most reliable measurement method would be to subject the entire muckpile to a sieve analysis, but this is obviously impracticable. Therefore, computational method based on image analysis have been developed. These include IPACS (Dahlhielm, 1996), Tucips (Havermann and Vogt, 1996), Fragscan (Schleifer and Tessier, 1996), Cias (Downs and Kettunen, 1996), GoldSize (Kleine annd Cameron, 1996), Wipfrag (Maerz, Palangio, and Franklin, 1996), Split Desktop (Kemeny, 1994), PowerSieve (Chung and Noy, 1996), and Fragalyst (Raina et al., 2002). In these methods, the size limits of the fragments forming the material are determined by image analysis on photographs of the muckpile. However, the computer software has some limitations. It does not take into account the third dimension of the muckpile, nor the size distribution of very fine fragments. In particular, the fragment size ranges below 2.5 to 3 cm cannot be determined, and therefore these cannot be included in the muckpile size distribution. However, the muckpile formed by a bench blast contains a wide range of particle sizes (Tosun et al., 2015)."

Oct 1, 2018

By X. Chen, G. Wang, D. Wan

Computational fluid dynamics have been applied for detailed modelling of particle-bubble collisions. The most accurate approach in the previous work is using the point particle method to treat particles and bubbles. Nevertheless, the sizes of particles and bubbles are generally bigger than the Kolmogorov scale in the high turbulence of the flotation environment, which makes the point particle method inappropriate. This paper describes particle-resolved direct numerical simulation on the collisions between particles (denoted as heavy particles) and bubbles (denoted as light particles) in a homogeneous isotropic turbulent flow field, and a comparison with the point particle method.. A largescale stochastic forcing scheme was implemented within the mesoscopic multiple-relaxation-time LBM approach to maintain turbulence intensity at targetted levels. Both kinematic and dynamic collision kernels were evaluated to study the correlation of total collision events and turbulent kinetic energy (TKE) dissipation rate. The results show that collisions between particles increase with the TKE dissipation rate as radial relative velocities between particles increase with it. In the particle-resolved simulations, the dynamic collision kernels were found to not match with the kinematic collision kernels as in the point particle method. Quantitatively, they were approximately 4 to 10 times smaller than the corresponding dynamic collision kernels. Therefore, it is not reasonable to estimate the kinematic collision kernel in particle-resolved simulations as its rationales are not valid. However, the collision behaviour can still be accounted for by means of the dynamic collision kernel since it is obtained from the direct statistical analysis of the collision events. Keywords: Lattice Boltzmann Method; particle-resolved simulation; multiphase flow; collisions

Jan 1, 2020