Faculty of Engineering and the Built Environment (ETDs)

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Optimisation of the mineral grading wind sifter separator for coal beneficiation
(University of the Witwatersrand, Johannesburg, 2024) Alade, Jimmy Joanah; Bada, Samson
The concept of wind sifting for particle separation has been successfully implemented for various concentration purposes. Diverse configurations based on this concept have been fabricated over many decades. It has been used in recycling, agriculture, electronic waste sorting, furniture, food and beverages, and mineral processing industries to some extent. The approach’s effectiveness stems from the capability of separating lighter particles from heavier ones. This study utilised an optimised version of the wind-sifter that was designed and fabricated by the author during his master's degree. The drawback experienced while testing the first prototype wind-sifting separator led to this investigation. This study used a computer simulation technique (the Lagrangian particle tracking method). This resulted in observing the effectiveness of the separation process in the newly designed separator. The design of the new separator was made flexible in its mode of operation by fabricating detachable collecting bins to the separator assembly. This means the optimised separator can be operated with or without the coal collecting bins, unlike the prototype version, which could only run with its bins. The design of the separator was done with the aid of Autodesk Inventor, and simulation was carried out using Star-CCM+TM computer software. The simulation tests were performed for different particle sizes (−6.7+3.35 mm), (−3.35+1.0 mm) and (−1.0+0.2 mm) at different airstream velocities. The optimal airstream velocities from the previous study (at a cut point of 1.6 g/cm3) were also used in this study when the separator was run with its bins. These airstream velocities were 6.0 to 4.0 m/sec, 4.2 to 2.0 m/sec and 1.7 to 1.0 m/sec for the (−6.7+3.35 mm), (−3.35+1.0 mm) and (−1.0+0.2 mm) particle sizes, respectively. A simulation was used to determine the airstream velocity ranges of the separator without collecting bins. These were 10.5 to 9.0 m/sec for the (−6.7+3.35 mm), 7.0 to 5.0 m/sec for the (−3.35+1.0 mm) and 3.5 to 2.5 m/sec for the (−1.0+0.2 mm) particles. For the –1.0 mm size faction, three particle size distributions (–1.0+0.1 mm), (–1.0+0.15 mm) and (–1.0+0.2 mm) were simulated. The best airstream velocities of 1.7 m/sec and 3.5 m/sec were achieved, respectively, for the closed and opened bins. The results of the simulation study led to the fabrication of the optimised wind sifter used in this study. From the sink and float test conducted on two sets of feed-coal (coal A and coal B), the extent to which the separator could beneficiate coal was determined. The sink and float analysis revealed that coal A has a higher ash content than coal B. Coal A, at (−1.0+0.2 mm) size iii fraction, has an ash content of 4.29% at 1.3 relative density (RD). This is followed by the (−3.35+1.0 mm) particle size with 5.55% ash content and the (−6.7+3.35 mm) size fraction with an ash content of 5.89%. At an RD of 1.5, coal A has a specific ash content of 16.65%, and coal B has an ash content of 13.56% for the (−6.7+3.35 mm) fraction. Upon separating with the wind sifter, the clean coal products from coal A have a higher ash content compared to those from coal B. Running the separator without the bins, clean coal products with cumulative ash content ranging from 22.42% to 19.44% for the (−6.7+3.35 mm), 24.61% to 21.43% for the (–3.35+1.0 mm) and 27.54% to 22.51% for the (–1.0+0.2 mm) fractions were obtained. For the particle size of (−6.7+3.3 mm) and with the bins closed, a clean coal product of 20.21% was obtained from coal A (feed coal with 37.38% ash content). A coal product with 19.55% ash content was obtained from coal B (from feed coal of 26.65% ash). A second-stage test conducted on a first-stage coal product of 23.48% ash content yielded a coal product of 21.79% ash and 80% yield for coal A at (6.7+3.35 mm). This trend was also observed for other first-stage products at the three particle sizes used in this study. The Ep values obtained from this separator ranged between 0.035 and 0.16, with the Ep values increasing as the airstream velocity was reduced. For the (6.7+3.35 mm) fraction, Ep values (Probable Error of Separation) of 0.035, 0.095, and 0.16 were obtained at 6.0, 5.0, and 4.0 m/sec air velocities, respectively. Overall, the cleanest coal product with 16.73% ash and 26.70 MJ/kg was obtained in this study from coal A at bin 2. According to the study’s results, the separator was highly adaptable. The separator could also be used for upgrading and pre- concentrating other minerals in the mineral processing industry.
Performance evaluation of reduced graphene oxide incorporated dye-sensitized solar cells for stable power generation
(University of the Witwatersrand, Johannesburg, 2024) Ikpesu, Jasper Ejovwokoghene; Iyuke , Sunny E.
Dye-sensitized solar cells (DSSCs) have emerged as a promising alternative to traditional silicon-based solar cells due to their low cost, easy fabrication, and high efficiency in converting sunlight into electricity. However, the performance of (DSSCs) is limited by the charge transfer and recombination processes at the interfaces between the different components of the device. In the recent years, Graphene Oxide (GO) and reduced Graphene Oxide (rGO) have been proposed as potential interfacial components to improve the performance of DSSCs. This research looked at the performance of reduced graphene oxide in dye-sensitized solar cells for sustained power generation. Most dye-sensitized solar cells have benefited from the usage of reduced graphene oxide. This research focuses on the performance of reduced graphene oxide in dye-sensitized solar cells for sustained power generation. Most dye-sensitized solar cells have benefited from the usage of reduced graphene oxide. This is due to its characteristics such as high surface area, superior transparency in the visible region, light absorption, and charge transport. Aerosol Assisted Chemica1 Vapour-Deposition (AACVD) was used to create a fluorine doped tin oxide (FTO) layer. The Hummer's Method was applied to synthesize reduced graphene oxide (rGO). Titanium (IV) oxide – reduced graphene oxide (TiO2-rGO) composite was synthesized at the photoanode via screen printing and spin coating, then inserted in DSSC using roselle dye as a natural dye sensitizer to investigate the cell performance. X-ray diffraction (XRD), ultraviolet diffuse reflectance spectroscopy, scanning electron microscopy/energy dispersive X – ray (SEM/EDX), and profilometry were used to characterize the synthesized/fabricated samples. Using a solar simulator and air mass A.M. 1.5 (100 mw/cm2), current-voltage (I-V) measurements were obtained to determine the performance of the cells. Tin oxide thin films doped with fluorine (F:SnO2) were successfully deposited on a glass substrate using the AACVD process at various doping percentages and the optical properties of the FTO and substrate layers were investigated using absorbance spectra. A low absorption value of 12% F: SnO2 resulted in a higher transmittance of 90% were achieved. This shows that the optical and electrical properties of the DSSC were altered by fluorine doped tin oxide. The results of the developed spin coated TiO –rGO Nano composites revealed that the Hall Effect increases with thin-film thickness iv while mobility increases with carrier concentration. The optical absorption results of TiO2–rGO nanocomposites demonstrate that as dopant amount increases, the band gap energy falls from 3.6 eV to 1.4 eV. The findings indicate that there is a strong interaction between Titanium dioxide (TiO2) and reduced Graphene Oxide (rGO), which could result in better visible light absorption and consequently improve light harvesting efficiency when utilized in a dye sensitized solar cell. Open circuit voltage (0.53 V), short circuit photocurrent (0.12 mA/cm2), fill factor (0.02), and photoelectric conversion efficiency (11.52%) were the simulation results for the cell parameters obtained for the DSSC manufactured using reduced graphene oxide. Meanwhile, the open circuit voltage (0.56 V), short circuit photocurrent (0.63 mA/cm2), fill factor (0.03), and photoelectric conversion efficiency (4.70%) of the DSSC without reduced graphene oxide were obtained. The power conversion efficiency of the dye-sensitized solar cell with graphene oxide was 6.82 % greater than that of the cell without graphene oxide. A four-week stability test was also performed on the DSSC fabricated with reduced graphene oxide to measure the extent of electrolyte deterioration. After the first 24 days, the short circuit current value reduced by 39% from its original value of 0.1190 mA/cm2. Under white light irradiation, the efficiency value of the DSSCs was found to be stable for the first 12 days before gradually decreasing to 24% of its initial value. The improved performance of DSSCs with reduced graphene oxide may be ascribed to an increase in electron transport efficiency and visible light absorption. When reduced graphene oxide was used, the performance improved due to increased light absorption, a wider range of absorption wavelengths, faster electron transport, and suppression of charge recombination. Based on this research, comparing the absorbance and transmittance of fluorine- doped tin oxide (F: SnO2) at 4%, 8%, and 12% with regard to wavelengths (ℷ) at 230 nm and 1100 nm; It shows that at 12% (F: SnO2), the lowest absorbance yields better transmittance, and increasing the cell's efficiency by 11.52%. The power conversion efficiency (PCE) of DSSCs demonstrates that DSSCs fabricated with reduced graphene oxide improved cell performance and outdoor stability. Which confirm that the TiO2 - rGO is a good material for solar application.
Flammability, corrosion resistance, and environmental friendliness of coal composites produced from various coal fines
(University of the Witwatersrand, Johannesburg, 2024) Vatsha , Mhlawakhe; Bada, Samson O.
The concept of recycling carbon-containing waste into secondary raw materials is highly promising for fostering a resource-efficient and circular economy, given the increasing scarcity of natural resources and growing population. The effectiveness of coal tar modified by air- blowing technique as a binder “pitch” for coal fines in the production of structural composites is highlighted in this study. In addition, the feasibility of commercial dimethylpolysiloxane as a binder for coal carbon composite production was assessed and compared to that produced using coal tar-pitch. The two coal fines (GG1 and GS) used in this study have an ash content of 84.02% and 62.27%, respectively, and can be classified as rock. Their fixed carbon content ranges between 5.44% and 16.27%, compared to coal tar (35.23%). The coal tar has a volatile matter content of 64.50%, and with the air-blowing pretreatment, the tar was converted to pitch with a low volatile matter content of 11.27%. A pitch with the highest fixed carbon content of 87.68% and total carbon content of 96.01% was produced. Various ASTM standard test methods were used in the investigation to characterise and evaluate samples, including mineral phases and functional groups in the raw and coal composites produced. The composites were fabricated using a circular mould with a diameter of 30 mm and a 40 mm square mould. In the study, it was found that composites with a low H/C atomic ratio had low water absorption. Additionally, composites with high volatile matter content had high water absorption. However, the sample with the highest water absorption (19%) was the GG1 50/50 coal tar pitch 400-composite, which falls within the range (0-25%) for building materials. The composites with an intense O-H group had high compressive and flexural strengths ranging from 106.58 to 344.71 MPa and 48.75 to 159.30 MPa, respectively. The flammability of all composites was low. The highest flammability mass ablation rate and linear ablation rate were found to be 0.008 g/sec and 0.00983 mm/sec, respectively. In terms of the corrosion rate, the GS 80%/20% dimethylpolysiloxane coal composite had the highest corrosion rate (0.081 μmpy), which is minimal compared to some commercial ceramic tiles. The composites' environmental friendliness was determined by leaching them at various pH levels. The test was conducted by comparing the concentration of heavy toxic elements in the solution to the leachable concentration threshold for waste management standards (NEM WA Act No. 59 of 2008). All composites were environmentally friendly, meeting the moderate risk leaching concentration threshold. The composites that were produced in this study from South iii African discard coal can be used in large quantities in the environment without any danger or hazards, as demonstrated. Based on this study's overall results, repurposing South African discard coal as carbon/ceramic composites for building materials could play a role in the country's Just Transition initiatives. In addition to waste reduction, this strategy could reduce operational emissions, improve circularity, and address associated environmental risks.
Development and Application of activated carbons from Avocado waste: Resource recovery for sustainable applications
(University of the Witwatersrand, Johannesburg, 2023) Mohale, Lehlohonolo; Mulopo, Jean
This research sought to produce activated carbons that could be used for hydrogen storage. The effect of hydrothermal pretreatment of the char, the effect of varying the activation ratio of KOH as the activation agent and the effect of activation temperature in producing these activated carbons were evaluated. Hydrothermal pretreatment of the char enhanced the properties of the resulting activated carbons. The best performing activated carbon was produced from the hydrochar pretreated at 200℃. It was observed that activation improved with increased activation agent concentration and activation temperature, to a point, and the best activated carbon was produced at 1:3 activation ratio and 800℃ activation temperature. This activated carbon had the highest total pore and micropore volumes of 1.45cm3/g and 1.16 cm3/g, respectively. The highest surface area of 2529.8m2/g was obtained, which is relatively higher than previously reported surface areas obtained from activated carbons created from coal or biomass. The porosity and the high surface area show well developed activated carbons that have desirable gas adsorption performance. The activated carbons had oxygen containing functional groups that aid in hydrogen sorption, the highest hydrogen sorption at 77K and 1 bar was 352 cm3/g, which supports the use of the produced activated carbons in the hydrogen economy. These activated carbons enable the circular economy. Well developed micropores were observed in the activated carbons produced through this work and their gravimetric capacity meets the DOE targets for hydrogen storage.
Fuelling change: Harnessing water hyacinth for Bio-Fuel, a catalyst for changein Hartbeespoort
(University of the Witwatersrand, Johannesburg, 2023) Shippon, Angelique; Goncalves, Kevin
The Hartbeespoort community has long grappled with the invasive water hyacinth, a menace causing ecological and economic harm to the man-made Hartbeespoort Dam since the 1970s. After research and interviews, it’s clear that trapped pollution is the core issue, rendering conventional control methods insufficient. In response, this architectural thesis presents Fuelling Change, an innovative solution merging agro-industry, natural water purification, and tourism through 5 sub-programs. The primary objective is to transform the water hyacinth challenge into a self- sustaining ecosystem that both generates income for management and enhances water quality. This involves a digester plant to control hyacinth growth through utilization, collaborating with local farmers to establish a closed-loop nutrient cycle, and rejuvenating the social fabric with a promising Waterfront initiative. Employing an Emancipatory research approach empowers the community, while integrating critical regionalism and biophilic design ensures authenticity and alignment with the area’s identity. The proposed design converts an ecological crisis into a catalyst for positive change, fostering socio-economic regeneration in Hartbeespoort. Agro-industry: industry connected with agriculture. Emancipatory research: define & add to list [ ii ] ABSTRACT
Bodies of cunicularity in supersonic flow
(University of the Witwatersrand, Johannesburg, 2024) Myburgh, Sabrina Gabrielle; Law , Craig
Prior studies outlined the success of using randomised High Porosity Cellular Material cyl- inders both numerically and experimentally, however showed limited applicability to real-life aerodynamics applications. The primary effect of supersonic flow over porous media is to attenuate the bow wave by reducing the angle of incidence and redistributing the flow field, significantly reducing wave drag. The aim of this work was to investigate the drag-reduction effect of organised porosity within conic bodies of revolution on the supersonic flow field. Various organised porous cone-cylinders were developed to investigate the effect of the porous structure on the flow field, including shock waves, momentum changes and flow structures in and around the por- ous body. Several conic profiles were investigated. A numerical and experimental investigation was carried out in steady, supersonic flow at Mach 3.5 (Re = 3.9 × 10−5). The conic models had a porosity of ≈ 60%. The blow down supersonic wind tunnel facility at the University of the Witwatersrand was used for the exper- imentation, where schlieren photographs were captured along with drag force measurements of the solid and porous baseline cones. Numerical CFD simulations were carried out for a wider range of porous configurations using ANSYS Fluent R22.2. The numerical, experi- mental and literature Cd and flow visualisation were used to validate the numerical method, showing good agreement across data sets. Certain cunicular arrangements effectively reduced the drag in some shapes, while others worsened the drag. The greatest drag reduction of 40% was achieved in the cunicular BS4 Ellipsoid. The change in drag was associated with three sources, namely wave drag, jet v interaction, and momentum addition by the jet. These changes resulted from the flow inter- actions occurring within the inlet, internal and venting structures. Changes in drag depended on several factors, including vent geometry, expansion ratio, exit angle, inlet geometry and the crossflow condition, to name a few. Wave drag reduction was dependent on shock at- tenuation and reducing the wave angle, which was generally ensured by the conic surface pores absorbing energy from the bow wave. The jet interaction and momentum recovery were dependent on vent expansion ratio, exit angle and crossflow condition. The jet interaction had the greatest increase on the drag of the system, however, the effects of this were mitigated by using low vent angles with correct expansion ratios to maximise momentum recovery from the jet. The effect of the combined system was specific to the particular case, where the solid cone shape greatly influenced the overall performance. The effect on drag reduction was cumulative, sensitive and highly dependent on the individual case. The cunicular system is a viable drag reduction mechanism in conic bodies, however careful balancing of the porous inflow, outflow, bow wave and venting conditions is required in order to achieve significant drag reduction.
Assessment of Quality Management in Major Projects in the Mining Industry in Botswana
(University of the Witwatersrand, Johannesburg, 2024) Pitswe, Odirile Boniface; Sunjka, Bernadette
While project performance is generally evaluated in terms of schedule, cost and quality performance, guidelines for project quality management are lacking, (Steyn and Nicholas, 2008). The Botswana mining industry is faced with problems of engineering projects which don’t meet the expected outcomes and most of the problems emanate around quality management and quality defects. This research project involved the assessment of quality management in major engineering projects in the Botswana mining industry by evaluating the level of adoption and implementation of quality management systems in major engineering projects, identifying the major causes of project failure, and evaluating the effectiveness of quality management system as employed in major capital projects. The research was focused mainly on Debswana Diamond Mining company as the major mining house in the country, with an objective to assess the maturity level of the company’s quality management system (QMS) and identify opportunities for improvement. A mixed method approach was used which involved archival research and survey research, the results of which were triangulated to corroborate the findings and remove bias. Archival research was conducted using the company document repository to review project retrospect reports, (Lessons learnt reports) and identify problems experienced during the implementation of different projects. These were correlated with common causes of project failures as identified in the critical literature review and cross referenced against survey results to further confirm them. The results indicated that the maturity level of the Quality Management system is at level 4 (quantitatively managed), where processes are measured and controlled. Gaps were identified that if rectified would move the maturity to level 5 (optimizing), where the focus would now be on process improvement. The gaps are mainly around operationalisation, lower-level employees training on quality management, optimisation of shared resources especially subject matter experts like project engineers, key stakeholder management, involvement and participation from end users and operational teams. The study came up with the top five (5) major causes of project failure being: 1. Shared resources and subject matter experts get overstretched between different projects and end up neglecting quality assurance. 2. Poor stakeholder management. 3. Lack of stakeholder involvement and participation in the project. 4. Inexperienced project team. 5. Unclear statements of expected quality outcomes.
Measurement of combustion airf low into burners in coal fired plants
(University of the Witwatersrand, Johannesburg, 2024) Manqele, Gladwell Sizwe; Schmitz, Walter
This research study is aimed at achieving accurate measurement of mass flow rates in large square industrial square ducts at Eskom’s boiler plants. For safe and efficient operation of Fossil Fuel Firing Boiler Plants, the utility has put in place the Fossil Fuel Firing Regulation Standard which requires that the Total Combustion Air flow be measured at exit from the air heaters, into the ducts. In this study, a sophisticated airflow measuring probe was acquired, herein the current study referred to the 14-hole Omniprobe. The accuracy was found to be within 5% in a free stream flow field. A Five-hole probe was calibrated in the free-stream wind tunnel. The calibration process enabled the derivation of the probe specific polynomials of Pitch, Yaw, Total Pressure, Static Pressure coefficients and velocity components. A prototype air duct was designed for the study to simulate air flow through square ducts with a 90⁰ bend as an abrupt flow disturbance. To achieve the objectives of the study, 6 planes were identified where air flow velocity profiles were generated using the equal area method. The modeling of the velocity profiles was conducted numerically, using CFD (Ansys Fluent), and experimental, using Pitot-static probe, Omniprobe, and a Five-hole probe. The mass flow rates as measured by the Pitot-static tube were found to be consistent at planes 1, 2, 5, and 6. The mass flow rate as calculated from the Pitot-static probe varied by 2.1% through the duct. This justified the selection of the Pitot-static probe as the reference for this study. The velocity profiles generated from the traverse measurements using the 14-hole Omniprobe showed an error in velocity measurements which are in the proximity of the wall. This can be attributed to the the wall effect. The mass flow rates of air calculated from the Five- hole probe measurements were found to be within 4% of the mass flow rate as calculated from the results of the reference probe in the 1st and 2nd planes upstream of the bend. After the 90⁰ flow disturbance bend, the accuracy drops to 13% at plane 5 and improved slightly at plane 6 to 11.7%. This is attributed to complex flow pattern at these planes. The study concludes that the Pitot-static tube remains the preferred instrument for use in measuring flow rates using the equal area method in large square ducts. The Five-hole probe can be applied where the flow field is not distorted in conjunction with CFD. The Omniprobe’s accuracy in measuring the velocity magnitude, and the angularity of the flow field was verified in an open stream wind tunnel. This study recommends exploring the use of an L-type 14-hole Omniprobe for application in large square industrial ducts.
Distributed Electric Propulsion on a Joined-Wing Air-Taxi
(University of the Witwatersrand, Johannesburg, 2024) Brand, Darren Mark; Schekman, S.
Urban Air Mobility (UAM) is a form of aerial transportation within urban areas with the main intention of easing traffic congestion. Electric Vertical Take-off and Landing (EVTOL) air-taxis are currently in development, but no single configuration has been identified as superior for UAM. There is still scope for alternate designs to be explored. A major obstacle to successful UAM operations is the combination of high energy requirements for VTOL and low battery energy densities, thereby affecting operational aircraft range. Aerodynamic efficiency has been identified as a critical factor for achieving maximum flight range while electric battery technology is matured. It is proposed that an air-taxi which combines Distributed Electric Propulsion (DEP) with a joined-wing may achieve superior aerodynamic efficiency compared to other air-taxi designs. A joined-wing air-taxi capable of carrying four passengers and a pilot has been developed with four alternative DEP configurations. These aircraft are herein investigated and compared against one another. A computational approach was followed using STAR- CCM+ to evaluate the flow characteristics and forces around the aircraft for both climb and cruise conditions. It was found that a “Non-DEP” configuration with four proprotors can achieve up to 5% higher aerodynamic efficiency than a DEP variant. However, this configuration suffers with poor lifting capability at high angles of attack. The sensitivity of aerodynamic efficiency to changes in the number of proprotors and their spacing was seen to be negligible according to this investigation.
Aerodynamic Force Variation on a Trailing MotoGP Motorcycle in a Corner
(University of the Witwatersrand, Johannesburg, 2024) Shaw, Craig Byrne; Boer, Michael
Motorcycle racing is a popular form of motor racing. The MotoGP category produces exciting and competitive races due to motorcycles following each other so closely. This has led to significant aerodynamic advancements being made in the MotoGP category over the past decade. Motorcycles and riders often race within the wake of a leading motorcycle as a result of this competitive racing. Racing in the wake provides an advantage on a straight due to the reduced drag force. This allows for greater acceleration and an opportunity to overtake the leading motorcycle. The effect of the wake on a trailing motorcycle in a corner has not been explored in depth. This research was focused on the aerodynamic force variation on a trailing motorcycle in the wake of leading motorcycle. The optimal position for the trailing motorcycle to gain an advantage over the leading motorcycle was determined subsequently. This was achieved using Computational Fluid Dynamics (CFD). The geometry of the motorcycle was obtained using 3D scans of a 1/18th scale model 2018 Repsol Honda RC213V. The geometry of the rider was drawn using CAD. Initial CFD models were created simulating the motorcycle and rider in a straight line to compare to existing published data for validation. The CFD cornering methodology was developed by Queens University in association with Siemens. The method makes use of rotating reference frames. This simulates the motorcycle and rider cornering at a constant velocity around a constant radius corner. Models were created for a singular motorcycle and rider at varying lean angles between 40 and 60 degrees with matched velocities and corner radii. The aerodynamic forces of drag, lift and side force were analysed on the motorcycle and rider for each case. The trends for these forces were determined relative to the changing lean angles. The drag on the motorcycle and rider increased non-linearly as the lean angle increased with the side force following a similar trend. The lift on the motorcycle and rider also increased non-linearly as the lean angle increased. These same CFD models were recreated with a second motorcycle and rider following a leading motorcycle to determine the effect the wake had on the aerodynamic forces. The second motorcycle and rider were positioned 1 characteristic length behind the leading pair on the same racing line. The drag on the trailing motorcycle and rider decreased as the lean angle increased. The lift on the trailing motorcycle and rider followed a similar trend to the leading pair with it increasing as the lean angle increased and the side force fluctuates as the lean angle increased. This resulted in the trailing motorcycle having a negative allowable change in forward acceleration relative to the leading motorcycle at lean angles lower than 60 degrees. The optimal position for a trailing motorcycle in a corner was determined by positioning the motorcycle and rider on various racing lines and following distances behind the leading motorcycle and rider. This created a grid pattern of the tested trailing positions. Two smaller racing line radii, three larger racing line radii and three different following distances were tested. The optimal trailing position at a 50 degree lean angle was found to be 1 characteristic length behind and on a racing line 1 characteristic width larger than the leading motorcycle. This position resulted in a positive allowable change in forward acceleration relative to the leading motorcycle around a corner radius of 125.86 m at 38.36 m/s. This iii position was tested around another two corner radii of 75 m and 150 m. This resulted in a negative allowable change in forward acceleration of around the 75 m radius corner and a greatly improved positive change in forward acceleration around the 150 m radius corner. From these results it was concluded that this optimal position is only viable around larger radius corners. It was approximated that this optimal position provides the trailing motorcycle an advantage around corner with radii larger than 86.8 m.

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