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By F. Yang, S. S. Long

Mixed fatty acids, such as oxidised paraffin soap, are frequently used as a substitute for oleic acid in flotation of scheelite in China. Not only because it is cheaper than oleic acid, but also because it is superior in flotation performance to oleic acid. This superiority is generally attributed to the mixed fatty acids' synergistic effect. In this paper, the synergistic effect of oxidised paraffin soap was investigated. We found it mainly consists of a series of saturated fatty acid salts, with six to nineteen carbon atoms. All the contained fatty acids were classified into four groups based on their chain length to make the research work practical. Also, the groups were labelled as 1, 2, 3, and 4 in order. The research was simplified into studying the synergistic effect of four equivalent collectors, instead of fourteen fatty acids. It is justified by the fact that neighbouring fatty acids are expected to have a similar flotation performance. The synergistic effect of the four groups of fatty acids was studied by single-mineral flotation with single groups, binary mixtures, ternary mixtures, and the full component, as collector respectively. The flotation performance index and synergy value were introduced to evaluate flotation performance and synergistic effect of groups, respectively. The results show that the mixture 1+2+3 has the strongest synergy of all followed by the mixtures 1+3 and 2+3. The mixture 3+4 and 1+2, on the other hand, have negative synergy. The synergistic effect of mixtures of groups indicate that being consecutive in length and a broad range of lengths are vital for fatty acids to enhance synergy. Group 3 is fundamental for the collecting action of 733 oxidised paraffin soap in the flotation of scheelite. The fatty acid soap in group 4 is not suitable for flotation due to its low solubility. Keywords: Mixed collectors, synergistic effect, scheelite

Jan 1, 2020

By D. Sethuram, P. G. Koppad, S. Iyengar, R. Shobha

TiB2 and CeO2 particle-reinforced Al6061 hybrid composites were manufactured using stir casting and hot rolling techniques. The base alloy and composites were hot-rolled at 500ºC and a 50% reduction was achieved through 12 passes. The effect of varying TiB2 and CeO2 particle additions on the microstructure and mechanical properties of the Al6061 matrix was studied. Scanning electron microscopy showed uniform dispersion of both the reinforcements, with good interfacial bonding. Microhardness and tensile properties like yield and tensile strength were found to be higher for hybrid composite with 2.5% TiB2 and 2.5% CeO2 compared to Al6061 alloy and other hybrid composites. The increased tensile strength is attributed to good dispersion and interfacial bonding between the particles and Al6061 matrix. Fracture analysis using a scanning electron microscope revealed ductile fracture for the Al6061 alloy and mixed characteristics of ductile-brittle fracture for hybrid composites

Oct 1, 2021

By B. McFadzean, N. Patterson, M. Becker, S. Geldenhuys

The retreatment of secondary tailings for platinum group metals recovery presents a range of potential challenges, which vary depending on the nature of the original ore and the type of pretreatment it was subjected to. These challenges include the prevalence of ultrafine particles, which promote slimes coatings on valuable minerals, hinder bubble-particle attachment, increase pulp viscosity, and lead to higher gangue entrainment; surface oxidation of minerals, which alters their floatability; and the presence of deleterious gangue minerals and residual platinum group metal species that are inherently difficult to recover by flotation. This study compares the batch flotation performance across a range of tailings samples from the eastern and western limbs of the Bushveld Complex. A complementary mineralogical analysis was conducted to gain deeper insights into mineral behaviour. The paper evaluates these findings to identify the key factors contributing to poor platinum group metal performance.

Mar 6, 2026

By Dick Stacey

Many open pit mines are now being mined at very significant depths, often at depths far greater than was originally planned. Even deeper open pits are also being planned, to depths that would be considered deep by underground standards. The heights of the resulting rock slopes are usually beyond the current experience and knowledge base. The exceptions are, perhaps, some very high and steep natural rock slopes. These natural rock slopes are also assuming greater significance owing to pressures of infrastructure development and consequent exposure of such infrastructure to the hazards of slope failure and landslides. Developments in road and rail infrastructure are also resulting in higher rock cuttings. Present understanding of the mechanisms of slope behaviour and failure for high slopes, and for slopes subjected to high in situ stress conditions, appears to be lacking. If the mechanisms of slope behaviour are not well understood, the validity of commonly applied methods of analysis of the stability of such slopes may be questionable. The papers in this specialist International Symposium, including papers on mechanisms and monitoring techniques, and case studies will contribute to the understanding of these issues. The Symposium has attracted good international participation, from both the attendance and authorship points of view. We are very grateful to all presenters and delegates for taking timeout of their very busy schedules to come and share their knowledge and we hope that all will benefit from this event. Thanks are due to the Organising Committee and to the members of our International Advisory Panel for the ideas, the contacts and the badgering, and to the Secretariat of the South African Institute of Mining and Metallurgy for the organisation.

Jan 1, 2006

By Willem J. Marais

The management of unpaved mine road networks on large surface mines rarely results in optimal road maintenance strategies and minimised total road-user costs. This is ascribed mostly to the complex and dynamic combination of variable road networks and loading and discharge points. In a dynamic mining environment - typically those mines in which production is managed by a centralised truck dispatch system ? there is no guarantee that a particular road maintenance intervention will contribute significantly to reducing total road-user costs or increasing productivity. Most large surface mines operating ultra-heavy mine trucks rely on an integrated on-board diagnostic data collation, communication and GPS-asset location system as a real-time fleet management tool. By extending this system to incorporate a multi-sensor analytical procedure in which specific truck vital signs are monitored and filtered, a road defect can be recognised and a trigger level set to relay the location of defects on the mine haul road to the centralised truck data management system. Previous work established the feasibility of the multi-sensor approach to road defect recognition on large mine haul trucks, and outlined the defect recognition, analytical and modelling issues and system limitations. This paper presents the development of the analytical procedure used as a basis for evaluating the truck on-board data to establish maintenance priorities amongst a network of mine roads. Following an introduction to the system architecture, the results of system field trials are analysed and the results discussed in the light of defect density and traffic volume as the primary variables in an approach to prioritising road maintenance. The paper concludes that by supplementing the existing mine communication and asset management systems, road maintenance can be managed on a near real-time basis and maintenance equipment dispatched to where most immediate benefit will realised from a maintenance intervention on the network, thereby generating the maximum improvement in service and reduction in cost per ton hauled.

Jan 1, 2008

By G. P. O’Malley, A. N. Nikoloski

One of the most promising options for extraction of copper from low-grade chalcopyrite ores by heap leaching, however, chalcopyrite is refractory and suffers slow leaching kinetics and poor overall extraction due to formation of a passivation layer on the particles. The solution composition is believed to strongly affect the formation of this layer. This paper examines the effects of the major cationic species of Fe3+/2+, Mg2+, Cu2+, and Al3+ and the anionic SO42− species in acidic ferric sulfate media with a composition simulating recycle heap leach conditions. It was found that altering the sulfate, iron or aluminium concentration had significant effect on the copper extraction, the concentration of copper slightly influenced the extraction, and the amount of magnesium had no appreciable effect. Also, iron and aluminium caused a change in the sulfate concentration, and the sulfate ions had the greatest influence on the extraction of copper under recycle leach conditions

Jan 1, 2023

By S. Polansky, J. Kolacz

The new sorting system has been developed to achieve efficient separation at low mineral content levels. The system employs high resolution X-ray sensors providing multi-energy analysis, thus giving maximal information about processed materials measurable by X-ray radiography. It makes it possible to analyse the internal structure of the particles and directly detect inclusion of minerals and metals like copper or gold. The paper describes sorting application examples for zinc, lead, copper and gold ore with low metal content below 0.1% of Cu. The sorting system still allows high efficiency analysis, quantification and removal of rock particles representing waste fraction with no metal or a negligible amount being uneconomic to process. This brings a huge advantage during pre-concentration, where almost no losses of valuable minerals in the waste fraction can be achieved. The presented sorting system has been developed by Comex and X-MINE EU Project Consortium. Keywords: X-ray sorting, ore sorting, XRF analysis, XRT analysis

Jan 1, 2020

By Y. Belloa, C. Dorfling

The presence of impurities such as Se and Te in copper sulfate leach solutions can have a detrimental effect on electrowinning efficiency. These elements can be removed from the solution by precipitation; sulfurous acid is commonly used as a precipitation reagent, while studies have also reported improved precipitation with the addition of metallic copper. This paper aimed to determine the effect of conditions used during the solution purification step on the characteristics of the precipitates that formed. Precipitation tests were performed in a batch reactor with copper sulfate leach solutions obtained from the base metal refinery of a platinum group metal producer. The effects of agitation rate (250 and 500 rpm), SO2 flow rate (4.4 and 5.8 mL/min.L), temperature (65 and 95°C) and metallic copper powder addition (0, 1 and 2 g/L) on the characteristics of the precipitates formed during the tests were determined using scanning electron microscopy. The major phases detected in the precipitates formed when using SO2 as the only precipitation reagent were elemental Se and Cu2Se. The introduction of copper powder led to the production of different sulfide phases for the experiments conducted at 65°C irrespective of the values of the other reaction parameters. At 95°C, Cu crystals, Cu2O and tiny inclusions of Cu2(Se,Te) were the prominent phases noticed in the precipitates produced from all the tests conducted with copper powder as precipitation enhancing reagent. Keywords: copper, precipitation, selenium, tellurium

Jan 1, 2020

By L. A. Cisternas, R. I. Jeldres, D. Calisaya

"Flotation of copper-molybdenum sulphide ores in seawater entails critical challenges such as selective recovery of molybdenite, effective pyrite depression, and reducing the lime addition required to reach highly alkaline conditions. It is essential that laboratory flotation tests aimed at solving these problems give reliable, reproducible results and indicate the correct approach for industrial operations. Rougher flotation of coppermolybdenum sulphide ores in seawater was investigated using two different cells: a modified Denver cell and a standard commercial cell. The effect of an organic reagent on the flotation performance was tested, and the fast/slow-floating model was used to describe the results. The modified Denver cell significantly improved the reproducibility of the flotation test results, due to technological enhancements such as the impeller being driven from below without a stator, which enables the whole froth surface to be scraped with a paddle at a constant depth and rate. Organic reagents are a promising alternative to inorganic reagents for depressing pyrite in seawater. However, further studies should be conducted to investigate their impact on molybdenite recovery, as well as to evaluate the possibility of depressing pyrite after molybdenite separation. The fast/slow-floating model was found to be appropriate for describing the flotation kinetics of the copper-molybdenum ores. The parameters are useful for comparing the performance at different conditions. IntroductionOwing to the increasing scarcity of fresh water, the use of seawater mining and mineral processing is becoming increasingly important (Cisternas and Moreno, 2014). Seawater can be desalinated by reverse osmosis, but this involves considerable costs, limiting it to the big mining companies (Akgul et al., 2008; Leidner et al., 2012; Ghaffour, Missimer, and Amy, 2013). Furthermore, desalination has environmental consequences (Lee, Arnot, and Mattia, 2011); for example, a desalination plant designed to process 2.5 m3/s requires an electrical energy supply of around 30 MJ/s. To supply this power demand, a thermoelectric plant burning bituminous/sub-bituminous coal mixtures at a thermal power generation efficiency of 35% might release around 1200– 1500 t of CO2 per day. Furthermore, the effluents from desalination plants are typically discharged into the sea, and their high temperature and ionic content inevitably modifies the marine environment, with unknown consequences. The direct use of seawater is, therefore, more attractive, but it also poses major challenges since seawater contains ions that adversely affect mineral recoveries. In particular, in the flotation of sulphide ores in seawater, the floatability of molybdenite is depressed (Castro, 2012; Laskowski, Castro, and Ramos, 2014)."

Jan 1, 2017

By J. Jacobs

The three-product cyclone was originally developed in Russia and is now extensively used in China. The cyclone has recently entered the South African coal industry, and with the obvious advantages that this item of process equipment offers our ever-evolving industry it is safe to assume that it will add value to dense medium circuits in South Africa. Some of the possible applications include: ? Producing multiple products using a single dense medium circuit. These can typically be a primary product with calorific value of 27.50 MJ/kg and a secondary (middling) product with a calorific value of 22 MJ/kg ? High-density separation with a low circulating medium density. Anglo Thermal Coal and Exxaro have pioneered the use of these units at Umlalazi and New Clydesdale respectively. Extensive test work has been performed at Umlalazi to determine the efficiency of the unit and to determine how it compares with the conventional DSM (Dutch School of Mines) cyclone. Some people in the coal industry were initially sceptical and expected the performance of the three-product cyclone to be inferior to that of the conventional dense medium cyclone. The results of the test work have, however, shown that the efficiency of the unit is comparable to that of the cyclones currently employed. A valid concern expressed is the control over the cut-point density of the second stage separation, and work is on-going to find the optimal way to control the secondary separation density. Theoretically, the secondary separation density can be manipulated by changing the orifices of the unit, especially the spigot of the secondary stage. This remains to be proven, and a series of tests is currently being planned. Whatever the result of these tests may be, the three-product cyclone definitely has a place in the South African coal processing industry as it offers a low OPEX and CAPEX solution for producing multiple products from a single circuit, as well as the ability to operate at very high separation densities, while making use of low-density circulating medium. Keywords dense medium separation, DSM, three-product cyclone, coal processing.

Nov 1, 2013

By O. K. H. Sheff

An editorial in the April 1990 edition of Mining Magazine is worth a wider audience in South Africa, particularly as the SAIMM enters its own centenary decade and the process of change in the minerals industry world-wide makes increasing demands on the professionalism of its leaders. The editorial considers the changing status of engineers, who up to the 1880s had been held in high regard by society. Alumina and bauxite Economists forecast a slower economic growth rate in 1990, but expect continued increase in demand for aluminum at a 3 per cent annual rate during the decade. Structural and numerical analysis Struceng & Femcad (structural analysis and finiteelement method) is a conference and exhibition that is to be held in Grenoble (France) on 17th and 18th October, 1990. It is sponsored by the Institute for Industrial Technology Transfer (ITT-International).

Jan 1, 1990

By C. Birch, M. Katuruza

"The purpose of this study was to demonstrate unmanned aircraft system (UAS) technology in opencast highwall mapping using the experience at Isibonelo Colliery in Mpumalanga Province of South Africa. In opencast mines, geological mapping has evolved over time and there have been challenges in extracting valuable information from exposed highwalls due to restricted access for safety reasons. A UAS was used at Isibonelo Colliery to conduct highwall mapping, using drone-based digital photogrammetry techniques. A demonstration survey was undertaken during February 2018. The highwall flyover demonstration was planned for two areas (North and South pits) where field control points were placed by the mine survey department. A contractor used a DJI Phantom 4 (Pro) for the highwall mapping. Raw data was processed within 48 hours and a 3D model of the mapped pit area was produced. Further data extraction included obtaining updated weathering and lithological contact elevations and thicknesses for use in short-term planning. The results showed a good correlation between the resource model and the UAS data model. The project was considered a success and highwall flyover mapping and is now standard practice at Isibonelo Colliery.IntroductionDetailed geological mapping is crucial to the understanding of the structure of any mineral deposit. Several mapping methods may be applied depending on the available exposure/outcrop and nature of the orebody; for example, coal deposits typically suboutcrop only, therefore an opencut highwall provides the best exposure for mapping the geology. Mapped information, when incorporated into a resource model (generated from exploration borehole data), improves the understanding of the orebody or coal seam. This research paper focused on the use of unmanned aircraft system (UAS) technology for pit highwall mapping to generate data for updating geological models and avail the latest information to mine planning to improve the short-term plans."

Mar 1, 2019

By Ri McCrindle

"Analytical Chemistry is moving rapidly towards a concept where technicians have to do no more than press a button and print the result from an instrument that is a featureless ""black box"". In this environment we must ask how much traditional ''wet chemistry"" is still required for undergraduate students.Methods that can be fully automated will become increasingly important. An example of such a method is that of the slurry nebulisation and ICP-OES analysis of precious metal concentrate. Grinding the sample and adding Triton X100 as dispersant, complete analysis time is in the order of 90 min as apposed to the traditional Carius tube method which could take as long as 24 h. For most of the elements studied, the results using ""in-house"" reference material for calibration and as samples as well were within the 95% confidence level. Elements of low concentration in the sample (As, Bi and Se) were not within that level."

Jan 1, 2014

For practical reasons all basic input data for the gold mines of the Anglovaal Group conform to a regular grid of averages of sample values within 25-ft squares in the plane of the ore body; individual sample values with their metric co-ordinates are input and converted by a computer program to the basic 25-ft square averages. At the Prieska copper mine the bore- hole data are forced on to a regular grid of 15-m squares corresponding to the coordinates of the grid points nearest to the actual borehole intersections. As for the gold mines the Prieska ore body, although some 3 to 30 m thick, is also dealt with on a two-dimensional basis (Krige, 1973). On the gold mines the data subjected to geostatistical analysis cover: gold values (in cm g/t), uranium values (cm kg/t), and channel widths (cm). The gold and uranium values are normalised on the basis of log (value plus constant) and all the geostatistical analyses are performed on these transformed values. The channel widths usually conform reasonably well to the normal distribution and are, therefore, not transformed. At Prieska the metal grades analysed cover the two main products, copper and zinc, as well as the impurities lead and bismuth; in addition the specific gravity values and the hanging- and foot-wall deviations from a projection plane are also handled. These were all previously used on an untransformed basis but because of problems associated with the proportional effect the lognormal-de Wijsian model is now used for some of the grade variables. The key computer pro- grams can be summarised briefly as follows:

Jan 1, 1981

By H. C. Voges

The concentration of cassiterite at Iscor's Uis Mine is described, and information is given on aspects of the concentration of iron ore at Thabazimbi and Sishen Mines. At Uis, a very Iow-grade tin ore is concentrated by three-stage jigging, spiral concentration, and tabling to give a high-grade concentrate with a recovery of 80 per cent of the tin. A Iow-grade tantalite-columbite concentrate is also produced. The possibility of recovering mica, the use of sluice boxes instead of spirals, and the recovery of cassiterite from minus 45 µm material are being investigated. At the two iron-ore mines, heavy-medium separation is applied to size fractions larger than 0,5 mm. The types of ferrosilicon and the circuits used for the recovery of ferrosilicon from the various dilute-medium circuits are described. The spiral-concentration plant being installed at Thabazimbi for the treatment of the minus 0,5 mm portion of the ore is described.

Jan 1, 1982

The influence of Harold Hotelling?s work in the field of mineral economics is both unusual and outstanding. In the 66 years since its development, theory surrounding the economics of exhaustible resources has only been significantly researched since the early 1970s. At that time a wave of research into the economics of exhaustible resources arose from the threat of global resource scarcity and continued into the late 1990s. Current East Asian and global demand for natural resources as well as mineral and metal commodities, has stimulated interest in the optimal and sustainable exploitation of exhaustible resources to the point that the subject is worthy of review. Hotelling?s theory and the assumptions that he made in establishing a model for the optimal exploitation of mineral resources at the industry level and at the level of the individual mine owner, are examined. He showed that the rate of increase inexhaustible resource prices should be equivalent to the market rate of interest and that in a market with rising prices the rate of extraction should be constant. In markets where demand is stable optimal exploitation requires that the rate of extraction should decline over time, while in a monopoly market he showed that the rate of extraction is retarded. In addition, the effects of cumulative production on costs and prices, the uncertainty associated with estimates of the resource stock, the impact of exploration and issues of intergenerational equity are examined. An analysis of the optimal price path, extraction costs and mineral rents at an industry level is presented as a model. An analysis of the rates of production and optimal benefits at the individual mine level including total, average and marginal costs on the optimal rate of production, is considered. Optimal extraction rates for a mine with a clearly defined concave positive cost equation vary according to the position on the marginal cost curve. The influence of discount rates and the size of the ore reserves on the rates of mineral extraction are also examined and could define the frontier of usefulness for the ?economics of exhaustible resources?.

Jan 1, 2007

By F. M. L. Mulaudzi

Metal dusting is a corrosion phenomenon that occurs in strongly carburizing gas atmospheres at elevated temperatures. Reaction kinetics and product characterizations of Alloys 602CA and 800 were examined by scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX) and X-ray diffraction (XRD).The results showed that Alloy 602CA is more resistant to metal dusting than Alloy 800. Visual examination and SEM surface analysis showed that Alloy 800 suffered metal dusting attack after a relatively short exposure period. The amount of coke deposits increased on Alloy 800 with increased exposure from 96 to 336 hours. X-ray diffraction on the reacted surfaces identified graphite and austenite in both alloys and some iron oxides/spinel for Alloy 800.

Jan 1, 2012

By J J. Pretorius, G M. Hoffmann

Utilisation of lower-grade (<60 per cent Fe) resources, not utilised in the current products, is crucial to ensure optimal resource utilisation and maintaining/improving future profit margins by reclassifying low-grade material to ore. The purpose of the Sishen Expansion Project (?SEP?) is therefore to investigate the technical and financial viability of producing up to an additional 10 Mtpa of new products at Sishen from material currently classified as low-grade materials. Jigging technology has progressed to a point where Sishen?s 50 to 60 per cent Fe run of mine (?ROM?) material, once considered as waste, can be beneficiated to produce a saleable 64 per cent Fe product. This has been confirmed through appropriate beneficiation testwork. Consequently, Sishen can now produce saleable product from material not currently included in the resource definition, increasing the resource base of the mine significantly and ensuring higher resource utilisation. Mine Planning utilised the geological models to produce detail planning schedules, reflecting the current and SEP plants separately, optimised to comply with product specifications of both the current and SEP plants and to confirm the viability of the low-grade resources identified as SEP feed material. The SEP products specifications have been derived by optimally matching iron ore market requirements with the revised resource base. A 64.0 per cent Fe lump product and a 63.5 per cent Fe fine product are the optimal SEP products. The SEP plant will be able to produce 10Mtpa at an average yield of 60 per cent and a lump to fine ratio of 62 to 38. The plant consists of five major sections namely crushing, material preparation, beneficiation, final product handling and quality control services. Maximum integration with the current Sishen plant was considered. Kumba currently has an agreement with Transnet to rail up to 23.5 Mtpa through the Sishen Saldanha Iron Ore Export Channel (?IOEC?). Transnet and Sishen Iron Ore Company have signed a Definitive Agreement that deals with the expansion of IOEC?s capacity, which increases Kumba?s entitlement from 23.5Mtpa to 35.0Mtpa. The detailed enviro-legal impact assessments for the SEP indicated that the project has low enviro-legal risk as a result of it being a brownfields project incorporated into the current Sishen operations.

Jan 1, 2006

By R. Letsaole, H. Mabowa, J. Sehat, J. Tshilongo, T. Rampfumedzi, N. Ntsasa, A. Mkhohlakal1

This study explores the use of co-collectors to enhance the recovery and determination of rhodium during fire assay with lead collection, followed by acid dissolution using conventional hot plate methods. Rhodium, a critical platinum group metal, poses analytical challenges due to its low natural abundance and complex chemistry. Among the co-collectors tested, palladium and tellurium demonstrated significantly improved rhodium recoveries, ranging between 100% and 120%, whereas silver resulted in poor recovery and higher error margins. These findings highlight that co-collectors can enhance the efficiency and sensitivity of platinum group metal analysis, although their effectiveness is dependent on the chemical interaction with the target element. Acid dissolution was essential to ensure complete digestion of prills prior to analysis, enabling accurate quantification of rhodium. Overall, the findings suggest that palladium and tellurium are effective co-collectors for rhodium determination in fire assay, while silver and lead flux alone are unsuitable. This work provides important insight into optimising fire assay procedures for reliable rhodium analysis, with potential benefits for platinum group metals recovery and economic evaluation.

Mar 6, 2026

By S. Purushotham, Y. R. Murthy, M. Narasimha, S. K. Tripathy, M. Kumar

Spiral concentrators are gravity-based separators widely used to beneficiate coal, heavy minerals and beach sand. It consists of a helicoid trough that spirals downward in the helical configuration around an axial column. The particle segregation takes place based on size and density under the influence of gravity as the particles spiral down within the thin water layer. In the last century, most design modifications of this equipment were based on trial and error based lab-scale experimentations and empirical approach. The use of Computational Fluid Dynamics (CFD) has gained interest in the past two decades to understand the underlying flow physics in the spiral concentrators. In this paper, we used CFD to model the fluid flow and investigate the particle segregation inside a conventional LD9 spiral concentrator. Firstly, the Volume of Fluid model was used to resolve the liquid-air interface. The liquid depth and flow field predictions for varying flowrates were validated against the experimental literature data. One-way coupled VOF-LPT model was then used to describe the particle dynamics in the spiral flow field assuming dilute particulate flow. Moderate dense particulate flow (20 vol.%) was then modelled using the Algebraic Slip Mixture (ASM) model. Four particle-phases representing particles of different sizes of dual-density were simulated, and the component particle segregation was analysed. Keywords: Spiral concentrator, two-phase flow, multiphase, discrete phase model, ASM model

Jan 1, 2020