Dr Ognjen Orozovic

Dr Ognjen Orozovic

Research Associate

School of Engineering

Career Summary

Biography

Dr Orozovic completed a Bachelor degree in Mechanical Engineering at the University of Newcastle (2008-2012). During this time, as part of an industry scholarship program, Dr Orozovic worked on a wide range of materials handling projects through TUNRA Bulk Solids. The exposure to the field of gas-solid flows sparked an interest, which resulted in an honours thesis on the transient modelling of granular dense phase pneumatic conveying systems. After graduating, a continuation of his honours work resulted in a PhD project on the measurement, characterisation and modelling of granular dense phase pneumatic conveyors through the key parameters of the flow.
 
Since completing his PhD in 2017, Dr Orozovic has been a Research Associate with the University of Newcastle and has worked on industry related projects and an ARC Discovery grant in pneumatic conveying, which is further examining the dynamics of granular dense phase via the implementation of in-situ inertial measurement units within the flow.

Qualifications

  • Doctor of Philosophy, University of Newcastle
  • Bachelor of Engineering (Mechanical), University of Newcastle

Keywords

  • Mechanical Engineering
  • Gas-Solid Flow
  • Dense Phase Conveying
  • Pneumatic Conveying

Languages

  • Serbo-Croatian/Yugoslavian, so described (Mother)

Fields of Research

Code Description Percentage
090406 Powder and Particle Technology 50
091399 Mechanical Engineering not elsewhere classified 50

Professional Experience

UON Appointment

Title Organisation / Department
Research Associate University of Newcastle
School of Engineering
Australia
Casual Academic University of Newcastle
School of Engineering
Australia
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Publications

For publications that are currently unpublished or in-press, details are shown in italics.


Journal article (3 outputs)

Year Citation Altmetrics Link
2014 Lecreps I, Orozovic O, Jones MG, Sommer K, 'Application of the principles of gas permeability and stochastic particle agitation to predict the pressure loss in slug flow pneumatic conveying systems', POWDER TECHNOLOGY, 254 508-516 (2014) [C1]
DOI 10.1016/j.powtec.2014.01.056
Citations Scopus - 7Web of Science - 5
Co-authors Mark Jones
2014 Lecreps I, Orozovic O, Eisenmenger M, Jones MG, Sommer K, 'Methods for in-situ porosity determination of moving porous columns and application to horizontal slug flow pneumatic conveying', Powder Technology, 253 710-721 (2014) [C1]

Two methods were developed to investigate the porosity of moving slugs in situ during horizontal slug flow pneumatic conveying. The first method consists in applying a permeabilit... [more]

Two methods were developed to investigate the porosity of moving slugs in situ during horizontal slug flow pneumatic conveying. The first method consists in applying a permeability model in combination with measurements of pressure loss and fluid velocity along the slugs. A review of existing models describing the resistance of porous structures to fluid flow revealed that the semi-empirical model of Ergun is particularly suitable to investigate the porosity profile along moving slugs. The second method consists in a direct determination method involving a slug-catcher able to catch a moving slug in a fraction of a second and simultaneously separate it into three horizontal layers. Those two methods were applied to analyse the porosity of naturally occurring slugs during pneumatic transport of polypropylene pellets. It was found that in contrast to common belief, slugs are slightly fluidised structures that do not display any porosity gradient over the pipe cross-section height. The slug porosity appeared independent of the gas conveying velocity, all slugs displaying an average porosity around 0.41, which is slightly higher than the bulk porosity of 0.38. Most of the slugs displayed a rear that is denser than the front. However, some slugs had a front that is denser than the rear while other slugs displayed a relatively constant porosity over the entire length. Those unique results refuting the commonly used hypothesis that slugs are compact structures give a new incentive to the area of slug flow pneumatic conveying. While bulk solids mechanics can no longer be applied to explain the stresses induced by moving slugs, the validity of other theories that imply that slugs are fluidised structures should be investigated. © 2013 Elsevier B.V.

DOI 10.1016/j.powtec.2013.12.023
Citations Scopus - 6Web of Science - 5
Co-authors Mark Jones
2014 Lecreps I, Orozovic O, Erden T, Jones MG, Sommer K, 'Physical mechanisms involved in slug transport and pipe blockage during horizontal pneumatic conveying', Powder Technology, 262 82-95 (2014) [C1]

Moving slugs of plastic pellets were investigated in-situ during low velocity pneumatic conveying in horizontal pipelines. Slug characteristics including the profile of pressure, ... [more]

Moving slugs of plastic pellets were investigated in-situ during low velocity pneumatic conveying in horizontal pipelines. Slug characteristics including the profile of pressure, pressure gradient, particle velocity, porosity, radial and wall shear stresses, aspect and behaviour were combined to obtain a complete picture of moving slugs. The objective was to gain unique knowledge on the physical mechanisms involved in slug formation, transport, and decay and the occurrence of pipe blockage. Slugs in both stable and unstable states were analysed. A strong correlation between particle velocity and wall stresses was found, which suggests that the stresses responsible for the high pressure loss characterising slug flow may result mostly from the transfer of particle impulses to the pipe wall. Most slugs were found to be denser at the rear where particle velocity was the highest, thus leading to slug shortening over time. This phenomenon was successfully modelled using both Newton's 2nd law and the ideal gas law and prediction of particle velocity showed good agreement with experimental values. In contrast, other slugs were found to extend due to the particles at the front moving faster than the particles at the rear. Pipe blockage was found to result from insufficient permeation of the slug by the conveying gas, indicating that sufficient material permeability is a condition for slug flow to occur. © 2014 Elsevier B.V.

DOI 10.1016/j.powtec.2014.04.058
Citations Scopus - 7Web of Science - 7
Co-authors Mark Jones

Conference (3 outputs)

Year Citation Altmetrics Link
2016 Orozovic O, Williams KW, Jones MG, 'The evolution of slug porosity characteristics in horizontal slug flow pneumatic conveying', 12th International Conference on Bulk Materials Storage, Handling and Transportation (ICBMH 2016), Darwin, Australia (2016) [E1]
Co-authors Mark Jones, Ken Williams
2016 Orozovic O, Williams KW, Jones MG, 'Investigations and modeling of the layer fraction in horizontal slug flow pneumatic conveying', ICBMH2016 Conference Proceedings, Darwin, Australia (2016) [E1]
Co-authors Ken Williams, Mark Jones
2015 Orozovic O, Williams K, Jones M, 'A model for the layer fraction in horizontal slug flow pneumatic conveying and comparison to the model of konrad', CHoPS 2015 - 8th International Conference for Conveying and Handling of Particulate Solids (2015) [E2]

The stationary layer of material between slugs in horizontal slug flow pneumatic conveying is an important reflection on the state and dynamics of a system. The gas-liquid analogy... [more]

The stationary layer of material between slugs in horizontal slug flow pneumatic conveying is an important reflection on the state and dynamics of a system. The gas-liquid analogy model of Konrad has been shown to accurately predict the layer fraction for a range of cases but the model breaks down near blockage conditions and does not consider material properties. A new model based on the rate of change of the layer fraction with respect to slug velocity was developed that accounts for material properties and is applicable at blockage conditions. Results from tests on polypropylene pellets were compared to the new model and the model of Konrad with both models satisfactorily predicting the layer fraction in the range of slug velocities that were observed for the material. At the higher extremity of slug velocity the new model predicted an earlier onset of a change in flow types than the model of Konrad which was supported by experimental observations but not enough data was obtained on the test material to compare predictions near blockage conditions. A material dependent constant in the new model was found for polypropylene pellets with further investigations needed to explore this constant as a predictive or classifying tool for materials and their ability to slug.

Co-authors Mark Jones, Ken Williams

Thesis / Dissertation (1 outputs)

Year Citation Altmetrics Link
2017 Orozovic O, Observations and Modelling of Flow Parameters: Reflected Insights into the Flow Mechanisms of Horizontal Granular Dense Phase Pneumatic Conveying, University of Newcastle (2017)
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Grants and Funding

Summary

Number of grants 6
Total funding $197,020

Click on a grant title below to expand the full details for that specific grant.


20183 grants / $59,240

Technical Assistance to Develop and Specify Materials Handling Simulation Design Criteria$33,000

Funding body: BHP Billiton Iron Ore Pty Ltd

Funding body BHP Billiton Iron Ore Pty Ltd
Project Team Doctor Dusan Ilic, Associate Professor Kenneth Williams, Doctor Jayne O'Shea, Doctor Jie Guo, Doctor Peter Robinson, Doctor Ognjen Orozovic
Scheme Research Gant
Role Investigator
Funding Start 2018
Funding Finish 2018
GNo G1800591
Type Of Funding C3111 - Aust For profit
Category 3111
UON Y

Iron ore blending operations and homogeneity improvement assessment$20,000

Funding body: Vale Metals (Shanghai)

Funding body Vale Metals (Shanghai)
Project Team Doctor Dusan Ilic, Doctor Jayne O'Shea, Doctor Peter Robinson, Doctor Jie Guo, Doctor Ognjen Orozovic, Associate Professor Kenneth Williams
Scheme Research Consultancy
Role Investigator
Funding Start 2018
Funding Finish 2018
GNo G1800670
Type Of Funding C3211 - International For profit
Category 3211
UON Y

Concept development for a novel iron ore pneumatic vacuum extraction system$6,240

Funding body: Scott Automation and Robotics Pty Ltd

Funding body Scott Automation and Robotics Pty Ltd
Project Team Associate Professor Kenneth Williams, Emeritus Professor Alan Roberts, Professor Mark Jones, Doctor Ognjen Orozovic, Doctor Dusan Ilic
Scheme Small Research Consultancy
Role Investigator
Funding Start 2018
Funding Finish 2018
GNo G1800740
Type Of Funding C3111 - Aust For profit
Category 3111
UON Y

20173 grants / $137,780

Validation and optimisation of the ShoulderMaster operation and design$50,000

Funding body: Department of Industry, Innovation and Science

Funding body Department of Industry, Innovation and Science
Project Team Associate Professor Craig Wheeler, Associate Professor Phil Clausen, Doctor Wei Chen, Associate Professor Kenneth Williams, Professor Mark Jones, Doctor Ognjen Orozovic
Scheme Entrepreneurs' Programme: Innovation Connections
Role Investigator
Funding Start 2017
Funding Finish 2017
GNo G1700557
Type Of Funding C2110 - Aust Commonwealth - Own Purpose
Category 2110
UON Y

Validation and optimisation of the ShoulderMaster operation and design$50,000

Funding body: Department of Industry, Innovation and Science

Funding body Department of Industry, Innovation and Science
Project Team Associate Professor Craig Wheeler, Associate Professor Phil Clausen, Doctor Wei Chen, Associate Professor Kenneth Williams, Professor Mark Jones, Doctor Ognjen Orozovic
Scheme Entrepreneurs' Programme: Innovation Connections
Role Investigator
Funding Start 2017
Funding Finish 2017
GNo G1700589
Type Of Funding C2110 - Aust Commonwealth - Own Purpose
Category 2110
UON Y

Pneumatic conveying research on the transportability parameters for stone dust conveying to the coal long wall$37,780

Funding body: Oaky Creek Coal Pty Ltd

Funding body Oaky Creek Coal Pty Ltd
Project Team Associate Professor Kenneth Williams, Doctor Ognjen Orozovic, Doctor Dusan Ilic, Professor Mark Jones, Doctor Jie Guo, Doctor Jayne O'Shea
Scheme Research Grant
Role Investigator
Funding Start 2017
Funding Finish 2018
GNo G1701626
Type Of Funding C3111 - Aust For profit
Category 3111
UON Y
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Research Supervision

Number of supervisions

Completed0
Current1

Total current UON EFTSL

PhD0.5

Current Supervision

Commenced Level of Study Research Title Program Supervisor Type
2017 PhD Modelling of Slug Pneumatic Conveying with an In-situ Microprobe Sensor PhD (Mechanical Engineering), Faculty of Engineering and Built Environment, The University of Newcastle Principal Supervisor
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Dr Ognjen Orozovic

Positions

Research Associate
TUNRA Bulk Solids
School of Engineering
Faculty of Engineering and Built Environment

Casual Academic
TUNRA Bulk Solids
School of Engineering
Faculty of Engineering and Built Environment

Contact Details

Email ognjen.orozovic@newcastle.edu.au
Phone (02) 4033 9026

Office

Room A711
Building NIER
Location Callaghan
University Drive
Callaghan, NSW 2308
Australia
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