TUNRA Bulk Solids Technical Articles


Analysis of Silo Asymmetry Normal Pressures due to Eccentric Discharge using DEM Simulation

Silos are widely used for storage of bulk solids in the mining, chemical and agricultural industries. The consideration of loads acting on a silo wall is a particularly important aspect of silo design and performance to ensure the integrity of the silo structure. The eccentric discharge of bulk solids from a silo can lead to asymmetry in the normal pressure distribution around the silo walls. The non-uniformity and eccentricities of the wall loads, causing bending stresses in the circumferential direction at various levels, can have serious structural consequences. Understanding how the wall loads are affected by eccentric discharge is an aspect of silo design of major importance. This article examines a range of discrete element modelling (DEM) simulations to investigate wall loads during eccentric discharge for a coal silo with only one of two outlets in operations. For further reading:

Analysis of silo asymmetry normal pressures due to eccentric discharge using DEM simulation (Australian Bulk Handling Review Jul/Aug 2019)


Investigation of Loads Acting on Flow Isolating Gates in Bulk Solids Storage Bins

Storage bins for bulk solids handling operations rely on flow isolating gates to prevent outflow of bulk solids during initial bin filling condition, as well as during periods of stoppages in the plant operation. Professor Alan Roberts combines an analytical review of gate load determination with an experimental study employing a large, pilot scale Train Loadout Bin handling iron ore to examine the design of TLO for train loading. For further reading:

Investigation of loads acting on flow isolating gates in bulk solids storage bins (Australian Bulk Handling Review Jan/Feb 2020)


On the Path to 100% Reliability in the Materials Handling Chain

The bulk materials handling supply chain consists of multiple transportation and storage operations for receiving, stacking, reclaiming, and transporting raw and processed iron ore materials. TUNRA Bulk Solids worked with Roy Hill to solve several materials handling challenges by using the Discrete Element Method (DEM), site experience and extensive knowledge on bulk behaviour. For further reading:

On the path to 100% reliability in the materials handling chain (Australian Bulk Handling Review Mar/Apr 2020)


A Case Study of Stacker Chute Analysis using DEM and Scale Modelling

The performance of bulk handling plants depends on all equipment that comprise the system operating efficiently without interruption, and poorly designed transfer chutes often become a costly bottleneck and maintenance nightmare even though the chute itself may appear to be only a small or low-cost part of the plant. In this case study, TUNRA Bulk Solids model a stacker chute in a stacker reclaimer using Discrete Element Method (DEM) and scale modelling. For further reading:

A case study of stacker chute analysis using DEM and scale modelling (Australian Bulk Handling Review Jul/Aug 2020)


45 Years of Bulk Solids Handling Research, Education and International Engagement

The ABHR looks back at the work TUNRA Bulk Solids has done for the bulk solids handling industry in Australia and around the world since it began in 1975. For further reading:

45 years of bulk solids handling research, education and international engagement (Australian Bulk Handling Review Sept/Oct 2020)


TUNRA’s Ten Commandments for Reliable Transfer Chute Design

One of the most popular topics in the bulk solids handling world is the appropriate design of transfer chutes for effective plant operation and reduced downtime. Transfer chute problems are by far the most common we deal with in our engineering projects, which involve the design or re-design of transfers and associated work, including material characterisation tests, calibration tests and DEM computational modelling. The engineers at TUNRA Bulk Solids have put together a summary with considerations for transfer chute design. For further reading:

TUNRA’s Ten Commandments for reliable transfer chute design (Australian Bulk Handling Review Nov/Dec 2020)


The Influence of Bulk Density Measurements on Stockpile Capacity Estimation

Stockpiles are some of the most common means of storing large quantities of bulk materials in industry sectors including mining and steelmaking plants, as well as in the fertiliser industry, ports, and others. They are normally used for surge capacity either to store material that will be processed later or to account for differences in throughputs along the handling chain. In this article TUNRA Bulk Solids explain the important considerations when determining bulk density, the difference between bulk density and compressibility, the development of improved testing methods and application to stockpile mass estimation for inventory purposes. For further reading:

The influence of bulk density measurements on stockpile capacity estimation (Australian Bulk Handling Review Jan/Feb 2021)


Approaches to Calibrating DEM Models of Cohesive Bulk Materials

In this article, Shaun Reid from TUNRA Bulk solids gives TUNRA’s take on the current state of DEM application to industrial bulk materials handling problems. Shaun discusses both the advantages and limitations of the method and shares key tips to ensure that DEM users are getting the most out of their analysis. For further reading:

Approaches to calibrating DEM models of cohesive bulk materials (March/Apr 2021)


In The Modern Environment are Tailing Dams Viable?

Tailing dams have been an essential part of the mineral’s extraction process. However, history shows that serious environmental and safety issues are associated with tailing dams. Dr Thomas Bunn from TUNRA Bulk Solids writes about options that can solve these problems and may be economically viable in the longer term. For further reading:

In the modern environment are tailing dams viable? (Australian Bulk Handling Review May/June 2021)


Dust in Bulk Handling Operations: Sources, Testing and Passive Control through Effective Design

There is no doubt that the creation and management of dust is an ongoing challenge. In recent times, there has been an increased focus on environmental and health concerns related to dust emissions in mining and mineral processing activities. Understanding the behaviour of dry bulk materials in different handling operations is of utmost importance for the design of ‘dust-free’ facilities. Dust remains a key challenge in designing and operating specific links in the materials handling chain. TUNRA Bulk Solids shares some of the testing and design strategies it has learned through research and collaboration to prevent dust emissions. For further reading:

Dust in bulk handling operations: sources, testing and passive control through effective design (Australian Bulk Handling Review Jul/Aug 2021)


Evaluating the Indentation Rolling Resistance Performance of Conveyor Belt Covers

As conveying distances and belt speeds continue to increase, greater emphasis is being placed on energy efficiency in belt conveyor design. As a result, TUNRA Bulk Solids has seen an increasing number of inquiries which focus on the testing and analysis of higher energy-efficiency conveyor belts and idlers. For further reading:

Evaluating the Indentation Rolling Resistance Performance of Conveyor Belt Covers (Australian Bulk Handling Review Sept/Oct 2021