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By Abhishek Kumar, T. G. Sitharam, Surender Singh

The height of tailings pond (TP) embankments is frequently raised to accommodate the ever-increasing volume of tailings released by the mining industries. Excess pore water pressure (EPWP) may develop during the height-raising operations, which can affect the overall stability of TP. This article presents a detailed stability analysis for the embankments of an existing TP, the height of which was increased twice utilizing downstream (D/S) and upstream (U/S) construction techniques. A rigorous two-dimensional transient fully coupled-stress-pore pressure analysis is performed in the finite element-based package RS2 to examine the build-up of EPWP during different stages of construction. Furthermore, an attempt is made to investigate the feasibility of future height raising, with due consideration given to the influence of embankment raising rates. Results from the analysis show a development of higher EPWP within the tailings deposit in comparison to the embankments of TP, indicating the development of an undrained-like condition. The study further reveals that the development of EPWP is highly affected by the rate at which embankments of TP are being raised. A higher rate of embankment-raising results in the development of greater EPWP in comparison to a lower embankment-raising rate, which may lead to the ultimate collapse of TP. Furthermore, based on the stability analysis, the height of existing TP can be further raised by 4 m (two lifts of 2 m height) utilizing the U/S construction technique. A thorough cost and benefit analyses are however required before implementing the results of the current analysis since the storage capacity of TP is reduced while raising by the U/S method.

May 16, 2023

By David L. Giles

The alkalic igneous province of Montana consists of centers of laccolithic and stock-like intrusive complexes with associated sills, dikes, and breccia pipes (e.g., Judith, Highwood, Little Belt Mts.); isolated plug-like mafic bodies (e.g., Smokey and Eagle Buttes); and clusters of kimberlitic diatremes and ultrabasic dike swarms (Missouri River Breaks). The province extends in a belt throughout central Montana from the North Absaroka Range in the south to the Sweetgrass Hills on the Canadian border. Intrusive activity ranged in age from Late Cretaceous to late Miocene, peaking at about 50 m.y, ago. Diverse types of significant epithermal gold mineralization occur at many of the laccolithic centers. This mineralization took place in large part during the waning stages of, or following, igneous activity. Large remnant travertine blankets in the region attest to comparatively recent hydrothermal activity. The quartz-pyrite-gold mineralization ranges from igneous- hosted stockworks or fracture sets (Zortman-Landusky and Neihart districts) and breccia pipes (North Moccasin Mts.) to replacement zones in flanking and upwarped Madison Group limestone (Gilt Edge and Kendall districts). The latter are mostly localized by intraformational solution breccias in the upper Madison, notably near porphyry contacts. Gold mineralization in the province was accompanied by varying amounts of silver, base metals, sulfosalts, and tellurides, with quartz, fluorite, carbonate, and barite and gangue. Gold occurs as auriferous pyrite, sylvanite, or in native form. Since the 1880's, primary gold production from numerous scattered deposits in the Judith, Moccasin, and Little Rocky Mountains, along with byproduct gold from the Neihart silver district (Little Belt Mountain), has totalled around 2 million oz. The major deposits were in the 1-2 million ton range at an average gold tenor of 0.3-0.6 oz per ton. Most of the ore was mixed oxide or carbonaceous sulfide ore and was treated either by amalgamation or by roasting-cyanidation. Current activity includes heap-leach operations on bulk- tonnage low-grade (approximately 0.03 oz per ton) ores at Zortman-Landusky, and several small-scale, experimental leach or mining operations on carbonaceous replacement ores, as in the Kendall district and Spotted Horse mine. Current exploration efforts for gold are focused not only in the old established districts, but also in and around other alkalic centers, which have been unproductive to date, such as the Crazy Mountains, Sweetgrass Hills, and Bearpaw Mountains. Target concepts in these efforts are porphyry-hosted stockwork or disseminated gold ores and Carlin-type replacement lodes in the flanking Madison or other favorable carbonate units.

Jan 1, 2013

By Keith L. Harris

Buoyed primarily by growing consumer spending, the economy rebounded from a weak second quarter. According to preliminary estimates released by the Department of Commerce, real gross national product (GNP) grew $2 1.9 billion during the third quarter, producing a seasonally adjusted annual growth rate of 2.4%, compared with a rate of 0.6% in the second quarter of 1986 and 4.1% for the third quarter of 1985 (table 1). Third-quarter real personal consumption expenditures and Government purchases of goods and services rose $42 billion and $7 billion, respectively, but those gains were partially offset by the continuing decline of gross private domestic investment, off $16 billion, and the growing trade deficit, up $11 billion. Three quarters of the growth in consumer spending occurred in the durable goods sector as consumers responded to discounted financing offered by automobile manufacturers attempting to lower inventories of 1986 vehicles, Increased purchases of other durable goods, such as furniture and home furnishings, also contributed to the strength of the durable goods sector. The success of the automobile inventory reduction program as well as weak factory output led to a $20 billion decline in inventory growth. Investment for housing and producers' durable equipment expanded, however, and mitigated some of the impact of slower inventory depending on gross private domestic investment, Capital spending for nonresidential structures declined for the third consecutive quarter. The declining capital spending and the growing trade deficit continued to be significant and interrelated problems for the economy. Real capital spending for new plants and equipment during 1986 is expected to decline 2.5% after rising 8.7% in 1985 and 15.8% in 1984 (table 2). It is likely that capital expenditures bottomed out in the second quarter and that they will expand in the third and fourth quarters. The first-half decline was partially attributed to uncertainty arising from the pending tax- overhaul bill. Furthermore, there is little impetus for corporations to invest in new capacity since factories are operating at less than 80% of capacity (table 3) largely because of the continuing growth of imports. The growth rate of the trade deficit dropped sharply in the third quarter to less than half that of the previous quarter. Low oil prices, declining auto- mobile and steel imports, and increased exports of agricultural goods contributed to this decline. The continued low growth of the economy caused the Federal Reserve System to reduce the discount rate for the fourth time this year (in late August), drop ping it to 5,596, the lowest level in about 9 years. Inflation, as measured by the fixed- weighted GNP price Index, continues to remain low, but rose from the revised second-quarter level of 1.7% to 2.596, mostly because of rising food costs.

Jan 1, 1986

By V. Bondarenko

The importance and necessity of gas hydrates deposits development followed by natural gas extraction is considered in the present paper. Analysis is given to world sources focused on methane hydrates formation conditions. Information covering the most perspective gas hydrate deposit of the Black Sea is presented in the article. Two most common methods of gas hydrates development ? thermo stimulation and inhibitor injection are analyzed presenting their comparative characteristics. Basic scientific trends and developments of underground mining department in the field of gas methane extraction from gas hydrates are scrutinized. Schemes and methods of natural gas hydrates development are shown together with formulas, parameters and factors influencing the extraction process. Also the analysis is given to the possibility of gas hydrates formation from methane-air mixtures of degassing wells from coal mines of Ukraine. Improved experimental unit for gas hydrates formation under laboratorial conditions is presented with its basic characteristics. General conclusions and basic tasks requiring further research are given in the end.

Aug 1, 2013

By Erik Sundström, Magnus Nygren

Having seen significant improvements to accident rates in the last 40 years, companies in the Swedish mining industry now show a greater focus on the development of safety cultures throughout their organisations and workplaces. However, there is a lack of research examining the different safety initiatives and strategies practiced in the industry today. This study explores the potential influence and consequences such initiatives may have on the development of safety cultures in the Swedish mining industry. Twelve interviews with experts on safety initiatives from four different Swedish mining organisations were conducted and analysed in a process based on qualitative thematic analysis to identify notable connections to safety culture development. The results of these interviews highlight proclivities in the implementation and use of safety initiatives such as subjects of focus, methods and desired effects. This enables the interpretation of the conceptualisation and methods for the development of safety culture in these organisations based on their approaches to safety development. We believe the results of this study can serve as support for discussions on safety culture development in the Swedish mining industry, and be of interest for international mining industries, in addition to approaches to research in this field. However, we also believe it is important to emphasise the opportunities to approach safety culture in mining from different perspectives than those common today.

Jul 19, 2023

By Melvin W. Jackson

The study of the excavation of large spherical cavities in salt formations first became of interest in 1958 when it was recognized that a large cavity could be of value in the study of the detection or concealment of underground nuclear explosions. Previously unpublished studies are reported in this paper and other studies reviewed relating to the excavation of large cavities in salt by mining ad by solution. Special emphasis is placed on the utilization of the Tatum salt dome (about 22 miles southwest of Hattiesburg, Mississippi) for the proposed site of a large excavated cavity. The U. S. Atomic Energy Commission has recently been studying such a cavity as Project Payette, but no details have yet been published. If Project Payette is determined feasible and work funded, it would eventually involve the firing of a nuclear explosive at the center of a large cavity.

Jan 1, 1969

By Orlando C. Gaspar

The textures of the ores, the fine mineral intergrowths, the complex distribution of the deleterious minor elements, and the low base metal contents in some ore types, pose many technological problems to the beneficiation of the volcanogenic massive sulphides occurring in the Iberian Pyrite Belt. In particular fine intergrowths of the base metal sulphides with pyrite impose extremely fine liberation sizes (Kao=15 to 25um). The mineralogical, textural and metallogenic studies have provided an understanding of the distribution of vertical and lateral metal zoning in the ore bodies. Mapping of the ore types, carried out by mine geologists, and the metal zoning patterns computed from data base have shown that ore types are distributed as ore lenses, and that vertical and lateral base metal zoning exists in several orebodies. Since ore processing efficiency is affected by ore textures, and because the same mineral often shows different textural features, a relationship between the textures of the feed ores and those of the middlings must be established for all ore types defined at the deposit scale. For supplying, on time, the information needed for the optimization of the concentration processes, empirical methods of determining the mineralogical and textural characteristics of the several ore types have been developed.

Jan 1, 1995

By Hugh M. Roberts

DEVELOPMENT at Steep Rock lake has given rise to renewed interest in the geology of the iron ore deposits in the Lake Superior Region and has implications of no small moment bearing upon methods of exploration in the Precambrian Shield generally. Following upon the Regional Lake Superior meeting of the American Institute of Mining and Metallurgical Engineers in August, 1941, the authors prepared a paper on the Steep Rock deposits, which appeared in the A.I.M.E. publication, Mining Technology, for January, 1943. Between Januar7 and April, 1943, exploration at Steep Rock was continued by means o vertical, Mesabi-type churn-drill holes put down from the ice. This drilling has enlarged the tonnage of ore previously known and has disclosed further facts relating to the origin of the ore. The added evidence, we believe, goes to support the hypothesis that the deposits were formed by a process of replacement due to upward-moving, iron-bearing solutions which came in as igneous after-effects. Accordingly, in presenting the subject to the Canadian Institute of Mining and Metallurgy, it seems best not to change our first explanation, but to prefix the original paper with an interpretation of the results of the more recent explorations completed after its publication.

Jan 1, 1943

The Bureau of Mines is the engineering arm of the Government for mineral resources. Its mission is to carry out laboratory and field studies that will assure the wise and effective development and use of our Nation's minerals, fuels, and underground domain in order to preserve the security and enhance the welfare of our people. Specifically, studies are directed to the means by which current and emerging demands may be met, the real cost of such achievements, and the assessment of related social and economic factors. Ways are sought to fulfill our material needs in a manner that minimizes occupational hazards to workers in the industry, reduces waste, and ensures that mineral raw materials are supplied and mineral-based products are used and are disposed of efficiently, without objectionable social and environmental costs. The headquarters of the Bureau of Mines is located in Washington, D.C. The Bureau's research and development program, however, is conducted at 19 research centers and laboratories located throughout the United States.

Jan 1, 1971

By M. B. Sizgoric

Quantitative mineralogy is used in a study done on an Inco Metals Company nickel sulfide occurrence from 'the Thompson area in Northern Manitoba. The study included: a) determination of the variations in chemical composition of the ore minerals; b) determination of the liberation of the ore minerals for the various types of ore and for different feed grinds; c) assessment of the preliminary mill test results by comparing the mineral distribution in the different tailings. Preliminary mill test results had outlined three main problem areas: 1) unacceptabiy low grade concentrate with, 2) very high weight recovery and, 3) low pyrrhotite rejection resulting in a high sulfur concentrate. The mineralogical study readily explained these results by showing that: 1) between 20 and 40% of the nickel in the feeds and 55 and 75% of the nickel lost in the tailings is associated with pyrrhotite. This accounts in part for the low grade of the concentrates obtained at high recoveries: 2) hexagonal nonmagnetic pyrrhotite constitutes over 90 percent of pyrrhotite. Since hexagonal pyrrhotite floats more readily than monoclinic pyrrhotite, this could be part of the reason for the undesirable high pyrrhotite recoveries into the concentrates. Further test work to establish both the optimal grind and the best conditions for pyrrhotite rejection is therefore mandatory.

Jan 1, 1981

By J. Fu

"Since it was first identified in 1817, selenium has received considerable interest. Native selenium and a few selenium minerals were discovered several decades later. With the increasing number of selenium minerals, the occurrence of selenium minerals became the focus of much research. A great number of selenium deposits were reported all over the world, although few independent selenium deposits were discovered. Selenium is obtained mainly as a byproduct of other metals, and is produced primarily from the anode mud of copper refineries. This paper presents a comprehensive review of selenium minerals, as well as the treatment of copper refinery anode slimes for the recovery of selenium. Our focus is on the selenium minerals, including their discovery and occurrence, and the distribution of selenium resources. In addition, the main methods of recovering selenium from copper anode slimes are summarized. IntroductionSelenium (Se) was first observed in 1817 in a laboratory (Greenwood et al., 1984). The discovery of selenium was made by the Swedish chemist J.J. Berzelius and J.G. Gahn, who isolated selenium from a red residue in sulphuric acid from pyrite mined at Fahlun, Sweden. Selenium was named from the Greek word selene (moon), since it resembled tellurium, which had been discovered a few years earlier and named from the Latin word tellus (Earth).After the first observation of selenium in the laboratory, selenium received considerable interest. In 1954, E.P. Kaiser pointed out that Se is enriched in sulphide ores and often associated with Bi, Co, Sn etc. (Kaiser 1954). In 1959, Hawley and Nichol investigated selenium in Canadian sulphide minerals, and presented the content of selenium in sulphide from several deposits of different types. They also proposed that Se is enriched in lowtemperature hydrothermal pyrite (Hawley and Nichol, 1959). The thermodynamic conditions for forming native selenium and selenium minerals in sedimentary rocks were discussed, as well as geochemical behaviour of selenium near the oxidation zones of sulphides in the 1970s (Howard III, 1977; Zhu et al., 2003). Zhu et al. examined the morphology, features, and genesis of native selenium from Yutangba, Enshi City, Hubei Province, China in 2004, and pointed out, from the different forms of native Se, that selenium can be activated,transformed, remobilized, and enriched at sites such as in the unsaturated subsurface zone or in the saturated zone (Zhu et al., 2005). The transport and deposition of selenium in felsic volcanic-hosted massive sulphide deposits of the Yukon Territory, Canada was studied and reported by Layton- Matthews et al. (2005)."

Jan 1, 2016

By J. D. T. Steyl

Anglo American Corporation and the University of British Columbia have developed a medium-temperature oxygen pressure leaching process for the extraction of copper from chalcopyrite concentrates in an acid-sulphate system (AAC/UBC process). Leaching is performed at 150°C and surfactants are added to disperse molten elemental sulphur from the unreacted sulphide surface to prevent liquid sulphur occlusion. Copper extractions of over 95% and elemental sulphur yields of around 60% were observed over a 2-hour average residence time in a continuous pilot autoclave. Sporadic blockages occurring under continuous conditions were found to be caused by the accumulation of molten elemental sulphur mixed with unreacted sulphide mineral. A batch programme of experimentation was undertaken to establish the reason for this phenomenon. Batch experiments were conducted at low pulp densities on concentrate samples with narrow size distributions and at similar solution compositions to those experienced in the pilot autoclave. The overall rate of chalcopyrite oxidation was shown, under approximately constant solution composition, to be a strong function of the total available mineral surface area. Initial copper extraction rates followed the shrinking particle kinetic model under intrinsic surface control. Deviation from shrinking particle kinetics was however observed after a certain oxidation time. Secondary electron images identified small (typically less than 20 µm) sulphur conglomerates at the point of deviation, which 'collected' unreacted chalcopyrite mineral particles and lowered the total mineral surface area available for oxidation. These sulphur clusters are thought to be the precursor for blockages experienced in the continuous pilot autoclave. These results emphasised the importance of fine grinding (P80 5-20 µm) and suggest that shorter residence times may minimise the formation of sulphur conglomerates in a continuous autoclave operating at medium temperature.

Jan 1, 2004

By Hans von Michaelis

There has been a renaissance in gold and silver extraction and recovery that has taken place over the last fifteen years, since the price of gold was freed from the $3510~ level. Despite major advances in such areas as carbon adsorption processes for gold recovery, refractory gold ore treatment, crushing and grinding, process control, etc., there still remain several gold and silver mineral processing frontiers. Frontiers related to environmental management present significant challenges especially in the USA. More than ever it is appropriate to optimize total economics by adopting a "systems approach" that integrates mining, mineral processing and environmental management.

Jan 1, 1993

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Jan 1, 1980

By Frank E. Lathe

During the war the National Research Council at Ottawa sent out questionnaires to the managers of nearly all the industrial plants in Canada. Inquiry was made as to the research equipment possessed, the number of research workers employed and the nature of the research problems which still remained unsolved. Practically all the companies reported that they had no special facilities for research, had no re-search workers and did not require the assistance of the National Research Council-because they had no research problems. Perhaps we have here one of the chief reasons why certain of our manufacturers find themselves unable to meet foreign competition. For hundreds of years the Indian tribes of northern Chile worked, in a small way, the copper deposits at Chuquicamata. They had no research problems and made no striking success of their mining operations. Then came an American company with a research problem, which they proceeded to solve. To-day the stock of that company has a market value of about $140,000,000.

Jan 1, 1926

By Brian Gettinger, Jared Barber, Richard Weatherly, Shannon Dunne, Jeff Masek, Chuck Wolf, Fazle Rabbi, Jack Canfield

During Hurricane Harvey over 60% of the 39 WWTPs, including the low-lying 25 MGD Sims North WWTP, and one third of the 382 lift stations owned and operated by the City of Houston were flooded resulting in extensive facility damage, loss of service and uncontrolled release of untreated wastewater into bayous and creeks. In response, the City has embarked on an effort to improve system resiliency by consolidating at-risk facilities with a network of deep sewer tunnels. These tunnels will provide secondary benefits to the collection system of augmenting the capacity of the existing 6,000 miles of sewer mains and lowering the collection system profile in poor performing areas. Investigations on the cost to mitigate the flood damages by raising the liquid stream processes at the Sims North WWTP is estimated at nearly $450 million. Instead of spending $450 million to raise the plant, the funds will be directed to providing a more robust and resilient wastewater system for the Sims basin area of Houston. The backbone of this new system is a 4.5-mile-long, 110 inch diameter deep gravity sewer tunnel that will convert a system heavily reliant on distributed lift stations to a majority gravity system with a deep consolidated lift station at the Sims South WWTP. This will also allow the City to address the flood prone infrastructure at Sims North and consolidate its operations into a single permitted outfall for this collection system. This approach is the outcome of a team effort focused on maximizing system resiliency and sustainability for the next 100 years. By thinking outside the box, the City of Houston will not only mitigate the flooding risk at Sims North WWTP, but also solve regulatory and operational challenges throughout the sewershed and deliver a winwin on multiple levels.

Jun 13, 2021

By Fiona Woody

Lime and calcium products are essential building blocks to the modern world, used to purify drinking water, preserve foods, control pollution, improve crop yields, stabilize soil, pave roads and support the production of steel, cement, glass and many other industrial processes. While lime is essential to society, it also has a sizable carbon footprint. Approximately 30 percent of the scope 1 greenhouse-gas emissions generated during lime production are related to fuel combustion, while the remaining 70 percent are created by the unavoidable chemical reactions during calcination.

Feb 1, 2026

By W. Kempson

"As has been noted on numerous occasions, the vertical shafts being sunk around the world are all tending to get deeper as we seek to take advantage of higher grades of minerals which can sometimes be found at greater depths. One of the challenges with these deeper shafts is the requirement to supply services to the mine’s operations at depth as well as the requirement to dewater the mine. Both the supply of water and the dewatering of mines is generally done using piping. With the greater shaft depths, this piping is now required to contain higher pressures as well as to accommodate changes in temperature resulting from normal mine operations. This paper will discuss the requirements for the design of high pressure piping in deep vertical shafts. The discussion will start with the general definition of the systems and the detailed design requirement. Once this is clearly outlined, we will discuss the options available for fulfilling these requirement as well as the advantages and disadvantages of each of the systems. We will finish with the installation recommendations and provide a basis for the maintenance of these systems. INTRODUCTION Piping in vertical shafts is used to provide a number of services in underground workings. These services vary depending on geographical location and the type of the ore body which is being mined. For example, in the Zambian Copper mines, one of the largest requirements for in shaft piping is for dewatering. Similarly in the Gold deposits in the West Wits basin as well as the deep level Copper deposits in Arizona, one of the largest uses for the piping is the supply of a cooling medium to underground workings to create a safe working environment (this can in the form of water or of glycol depending on the application). In South Africa, systems were installed which used the hydrostatic head which is generated from supplying chilled water to mines whose depths exceeded 2,000 m below surface. This chilled water was supplied as a closed system, allowing for high pressures to be generated which was then used to supply useful work (for example, Rock Drills, Face Cleaning and other ancillary services) whose power was traditionally supplied by compressed air or electricity. This system was initially researched by Chamber of Mine in South Africa. The design pressure range of these systems is 14 MPa to 18 MPa."

Jan 1, 2019

By J. E. Dreier, R. E. Scheffel, A. Guzman

"This paper outlines a comprehensive, cost-effective testing program for the acid-ferric sulfate heap leaching of oxide, supergene and primary copper ores. It is based on extensive experience in copper heap leaching and uses the many technological advances in the field developed over the past several decades. The approach described requires firstly a detailed resource evaluation, then a hydrodynamic characterization of representative samples and, finally, a focused metallurgical testing program. The principles communicated here can be applied to other acid leachable minerals. The program varies considerably from conventional testing in its disciplined, orderly, step-by-step approach, its application of hydrological and chemical principles to leaching, and its reliance on fewer, more tightly controlled column tests. The purpose of the test program is to optimize the financial, time and other resources devoted to the program, while minimizing the financial risks to the development company or companies and the project funding providers. IntroductionThe major goal of any process development testing program should be the successful implementation of the project. With respect to heap leaching, the metallurgical testing program plays a critical role in the larger objective, as described in Scheffel (2013, 2014). McNulty’s series of papers (1998, 2004, 2014) confirm that the success of any project is directly proportional to the extent and quality of the testing program on which the process is designed.Therefore, a key development objective is to conduct a well-focused metallurgical test program. While the primary focus of this paper is copper, the acid leaching of any substance would benefit from a similar approach.This paper addresses primarily the sulfate system, which is compatible with the bioleaching of sulfide minerals. Nicol et al. (2011) described the advantages of the chloride leaching of copper sulfide minerals. United States patents Nos. US 2009/0173188 A1, US 8,597,933 B2 and US2015/0232963 A1, assigned to BHP Chile Inc. and BHP Billiton S.A. Ltd, describe methods for both the oxidative and nonoxidative leaching of primary and secondary copper sulfides. Reyes (2013) and Ipinza and Flaquer (2014) described commercial applications of chloride-based heap leaching. The testing disciplines discussed in this paper will also apply to the development of an acidic chloride leaching system."

Jan 1, 2016

By A. J. Paul, K. O. Yu

"Today, foundries are moving towards the use of models and design tools to gain a competitive advantage in producing castings of high desired quality. This leads to a growing alliance between foundries, software developers and researchers seeking to model, visualize and understand the phenomena taking place during the casting process. In addition, there is a need to develop affordable techniques to produce parts in small lot sizes. This leads to the development of a Flexible Manufacturing System consisting of: (1) up-front computer-aided engineering; (2) computer integrated proto typing with solid freeform fabrication; and (3) fabrication of the actual mold and related equipment to cast the part.This paper discusses some of the developments that are taking place today in the areas of modeling the physical phenomena during the casting process as well as towards developing a Flexible Manufacturing System for producing cast parts. Areas that require most work involve prediction of defects and mechanical properties using simplified analyses. In addition, electronic data sharing for collaborative engineering between geographically dispersed team members is also discussed. Case studies are presented showing successes as well as failures.IntroductionCasting, one of the oldest forms of metalworking, has recently seen a flurry of developments in the area of solidification modeling. These developments have come about after the realization that, in order to stay competitive, foundries need to reduce their scrap rate and production costs, and increase casting quality. Even though this is not new knowledge for foundry engineers, the tools to help them achieve this goal are just being developed and put in place for use by foundries. Several state-of-the-art software packages are currently available to analyze the solidification behavior in complex shaped castings. These packages make use of several different approaches for solving the various problems associated with casting processes. The overall architecture of a comprehensive solidification modeling system is shown in Figure 1."

Jan 1, 1994