Showing items 1 - 20 of 30

Anaerobic digestion for sustainable energy : a brief review

- Kumba, Tresor K., Akinlabi, Esther Titilayo, Madyira, Daniel M.

Analysis of the Zimbabwe biodigester status

- Kajau, Garikai, Madyira, Daniel M.

  • Authors: Kajau, Garikai , Madyira, Daniel M.
  • Date: 2020
  • Subjects: Organic Loading Ratio , Hydraulic Retention Time , Anaerobic and Aerobic Bioreactors
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/465134 , uj:41582 , Citation: Kajau, G. & Madyira, D.M. 2020. Analysis of the Zimbabwe biodigester status , DOI: https://doi.org/10.1016/j.promfg.2019.05.079
  • Description: Abstract: A perfectly working biogas digester is an asset .as it provides gas to the owner and also helps to save money and reduce overdependence on the national electricity grid for energy needs. A biogas digester, can be a multi-functional asset to its owner. Its purposes can include energy recovery, sanitation, waste management and fertilizer production. Equally important, is the fact that biogas is a high-quality fuel, which can be used for heating and vehicle power. This greatly reduces the overdependence on fossil fuel derived energy and ultimately results in the reduction in environmental impacts such as global warming and pollution, improve sanitation and reduce demand for charcoal for cooking. Moreover, this technology also produces a high-quality organic fertiliser. This study sought to understand the factors that affected the current status of disrepair of biogas digesters in Zimbabwe. 85% of the sampled digesters in Zimbabwe did not have the following: (a) temperature control and monitoring mechanism (b) proper gas pipes (d) gas detector sensors (e) flow meters (f) agitation mechanism (g) heating systems (h) water traps. Based on these findings, it became apparent that poor workmanship can be a major factor inhibiting digester performance.
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CFD evaluation of premixed and non-premixed models as suitable representatives of fixed-bed biomass combustor freeboard

- Lekwana, Mathope T.L., Madyira, Daniel M., Oosthuizen, Gert A., Makonese, Tafadzwa,N.

  • Authors: Lekwana, Mathope T.L. , Madyira, Daniel M. , Oosthuizen, Gert A. , Makonese, Tafadzwa,N.
  • Date: 2016
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92312 , uj:20214 , Citation: Lekwana, M.T.L. et al. 2016. CFD evaluation of premixed and non-premixed models as suitable representatives of fixed-bed biomass combustor freeboard.
  • Description: Abstract: This paper presents a comparison of the performance of two numerical (CFD) models with experimental data obtained for a fixed-bed biomass domestic cooking stove. The two numerical models are two different representations of the possible behavior of the gas region of the combustor under consideration. The one model considers the pyrolysis products emanating from the fuel bed to be premixed with the oxidant (air), while the other model supposes that the pyrolysis products combusting in the freeboard enter this region through a stream that is separate from that of the oxidant. The geometry of the combustion chamber of the stove from which the experimental data was obtained is cylindrical with l lcm diameter and 25 cm depth. The study particularly monitors the exit flame temperature of the cylindrical combustor through the use of k­ type thermocouples in the experimental case. The fuel used in the experiment is peanut shells. The premixed model achieved an exit temperature of 435K while the non-premixed model achieved an exit temperature of 747.9K. On the other hand, the highest experimentally obtained temperature is 778.lSK whereas the average experimentally obtained temperature is 641. lSK. Consequentl y the non-premixed model is chosen as the better representative of the freeboard.
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Characterizing sunflower oil biodiesel blends as alternatives to fossil diesel

- Madyira, Daniel M., Nkomo, Zanele, Akinlabi, Esther Titilayo

  • Authors: Madyira, Daniel M. , Nkomo, Zanele , Akinlabi, Esther Titilayo
  • Date: 2012
  • Subjects: Fossil diesel , Sunflower oil , Biodiesel
  • Type: Article
  • Identifier: uj:4666 , ISBN 978-988-19252-2-0 , http://hdl.handle.net/10210/10046
  • Description: This paper reports on investigation into the feasibility of using sunflower oil based biodiesel blends as alternatives to fossil diesel fuel. The current global reliance on fossil fuels is coming to an end. This is driven on one hand by the dwindling global fossil fuel reserves and the understanding of the consequences of carbon accumulation in the atmosphere on the other. Dwindling reserves continue to drive global fuel prices upwards with negative effects on economic performance. Continued accumulation of carbon dioxide in the atmosphere is perceived to be responsible for the Greenhouse Gas (GHG) effect. This dual problem can be addressed by using alternative renewable fuel sources, which guarantee continued supply while maintaining global carbon neutrality. Biofuels are now largely recognized as viable options. Some of the challenges of using biodiesel in conventional diesel engines are their low density, which leads to low calorific value and acidity levels that threatens the structural integrity of the engine. Blending biodiesel with petroleum diesel can mitigate these effects and lead to better performing fuels. Fuel characterization is therefore essential to establishing notable similarities and differences between biodiesel and fossil diesel, and in determining optimum blending proportions for more effective use of biodiesels. In this investigation, biodiesel was produced from commercial sunflower cooking oil using the batch trans-esterification process with methanol in the presence of Sodium hydroxide catalyst. The characterization of the biodiesel was then conducted using Nuclear Magnetic Resonance (NMR), bomb calorimetry, acidity and flash point analysis, sulphur content tests and Gas Chromatography (GC). Blends ranging between 5% and 50% biodiesel concentration in Ultra-Low Sulphur Diesel (ULSD), in increments of 5% were analyzed. Results obtained confirmed that biodiesel has lower calorific value than ULSD, implying higher fuel consumption. The high flash point, almost at a temperature twice as high as that of ULSD, though advantageous for storage and transportation, results in poor ignition. The results also suggest that an increase in concentration of biodiesel leads to larger difference in properties between the blend and the ULSD. The pH value of biodiesel was found to be lower than that of ULSD which compromises engine structural integrity. Biodiesel’s chain length was found to contain an average of 19 carbons which makes it a viable option when compared to ULSD. Despite the relatively inferior properties measured, biodiesel still remains one of the most attractive fuel options.
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Design of chilled ceiling displacement ventilation for direct expansion HVAC system

- Madyira, Daniel M., Kaymakci, Abdullah

  • Authors: Madyira, Daniel M. , Kaymakci, Abdullah
  • Date: 2016
  • Subjects: HVAC , Displacement ventilation , Chilled ceiling
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92201 , uj:20201 , Citation: Madyira, D.M. & Kaymakci, A. 2016. Design of chilled ceiling displacement ventilation for direct expansion HVAC system.
  • Description: Abstract: Displacement ventilation is a low cost ventilation technique used in distributing conditioned air in Heating, Ventilation and Air Conditioning (HVAC) systems. This is a ventilation strategy well suited to significantly reduce building energy consumption in this age of high energy costs, global warming and climate change. This is achieved through the leveraging of natural buoyancy driven flow in the conditioned space in a way that minimizes energy expenditure in supply and extraction fans. In addition, the conditioned air is supplied at higher temperature implying lower energy demand for cooling units. The global legislative move towards greener buildings demands the use of sustainable and energy efficient air conditioning systems of which displacement ventilation makes a major contribution. One of the challenges in using displacement ventilation is the stratified temperature distribution in the conditioned space. The temperature gradients between the ceiling and the floor can lead to decreased comfort conditions. One approach to overcome this problem is to use the chilled ceiling. How does one size the chilled ceiling system in such cases? The purpose of this paper is to present a detailed design analysis of a displacement ventilation chamber that includes chilled ceiling. The chamber utilizes an under floor air supply system into a conditioned space configured to represent typical office space. The construction and performance testing of the displacement ventilation testing chamber is then reported in a subsequent paper.
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Design of the bio-digester for biogas production : review

- Ramatsa, Ishmael M., Akinlabi, Esther Titilayo, Madyira, Daniel M., Huberts, Robert

  • Authors: Ramatsa, Ishmael M. , Akinlabi, Esther Titilayo , Madyira, Daniel M. , Huberts, Robert
  • Date: 2014
  • Subjects: Biogas digesters
  • Type: Article
  • Identifier: uj:5016 , http://hdl.handle.net/10210/13156
  • Description: This review is a summary of different aspects of the design and operation of biogas digesters. Three types of digesters were reviewed, that is, the plug flow, floating drum and the fixed dome digester. Biogas is one of the products formed during the anaerobic digestion process. Anaerobic digestion is dependent on several factors such as the pH value, feeding material, temperature, pressure, organic loading rate, retention time and the Carbon-to-Nitrogen (C/N) ratio. The shape of the digester and the material for construction are also considered important during design stage.
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Determining optimum parameters for manual compaction of loose biomass

- Madyira, Daniel M., Kaymakci, Abdullah

  • Authors: Madyira, Daniel M. , Kaymakci, Abdullah
  • Date: 2016
  • Subjects: Briquetting , Loose biomass , Optimum parameter introduction
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92227 , uj:20205 , Citation: Madyira, D.M. & Kaymakci, A. 2016. Determining optimum parameters for manual compaction of loose biomass.
  • Description: Abstract: Significant amounts of loose biomass are produced annually through agricultural and forestry activities. It is common practice to burn these loose biomass deliberately after harvesting or in accidental veld fires in the case of forestry. This energy could be harnessed for cooking and heating. The challenge with the use of loose biomass lies in its low density and hence low energy content which can be improved through densification. The aim of this paper is to determine the optimum densification parameters that can be used to develop manual briquetting technologies to empower poor communities to harness the energy available in loose biomass that they dispose annually. This forms part of a larger project aimed at developing off grid biomass value chain technologies. Using loose grass and loose leaves, experimental data revealed an optimum density of 1250 kg/m3 and a corresponding densification pressure of 40 MPa. In addition, a comparison of the thermal profile of solid round and round hollow briquettes showed more superior performance of the round hollow briquette based on recorded maximum combustion temperatures. Briquettes with a hole in the middle are therefore preferred to solid briquettes.
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Development of a validated numerical model of an unreinforced T-section pipe for large dams

- Naicker, Ashley, Madyira, Daniel M., Mashinini, Peter M.

Development of container based community factories

- Madyira, Daniel M.

  • Authors: Madyira, Daniel M.
  • Date: 2016
  • Subjects: Community factories , Container factories , Home lighting system
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/216957 , uj:21578 , Citation: Madyira, D.M. 2016. Development of container based community factories.
  • Description: Abstract: The main obstacle to electrification in Africa is not constructing power stations and building overhead power lines. It is working out how to help the region's households acquire sustainable energy with limited and irregular cash flows, little collateral and no access to credit. They cannot afford to pay for the huge investment needed to bring electricity to them. Even if the electricity was brought to them, most can barely afford to pay for usage. This problem can only be addressed by providing tools that bring wealth to the communities. After water, food and shelter comes the need of lighting to extend the productive hours of the day. The Department of Mechanical Engineering at the University of Johannesburg, in collaboration with ! Ecovest, a South African upcoming small scale enterprise, developed an innovative solar home lighting solution that can be manufactured off the grid in a community based container factory. Solar lighting is significant for many without electricity and the developed solution allows the Sun to pay to eradicate expensive unsustainable on-grid energy. The container based solution empowers the community to create jobs and generate wealth while producing affordable and durable products due to reduced distribution and marketing costs. In existing and emerging markets, the gross product cost includes the costs of distribution which is well developed in existing markets but poorly developed in the emerging African market. Additionally, existing markets innovate incrementally (features of products) whilst emerging markets innovate radically (sustainable technology). Moving users from hazardous and expensive open flame solutions like candles to solar home systems, provides a more sustainable st! andard of living for off grid living.
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Development of the loose biomass briquetting value chain

- Madyira, Daniel M.

  • Authors: Madyira, Daniel M.
  • Date: 2016
  • Subjects: Agricultural residue , Biomass , Loose biomass
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/217127 , uj:21601 , Citation: Madyira, D.M. 2016. Development of the loose biomass briquetting value chain.
  • Description: Abstract: Biomass (roundwood, agricultural residues, forestry residues, organic municipal waste) has the largest carbon reserve with potential to replace unsustainable fossil energy sources. Furthermore, off grid communities produce significant amounts of loose biomass through agricultural and forestry activities. These include maize stalks, tobacco stalks, ground nut leaves and stalks, tree leaves, elephant grass etc. These are traditionally burnt in fields after harvesting. In addition, annually, forestry residues such as elephant grass, yellow thatching grass, dry tree leaves etc. are destroyed in perennial veld fires. Such loose biomass can be harnessed for cooking and heating and thus minimise the use of round wood, which results in defor! estation that cause desertification if not done sustainably. The major challenge in harnessing energy from loose biomass is their low energy density. This can be overcome by developing loose biomass briquetting technologies. This paper reports on the development of loose biomass briquetting technologies at the University of Johannesburg over the past five years. These include shredding, pre-treatment, compaction, off grid solar drying, and combustion. Briquetting required the selection of good feed stock and binders. Cow dung and cactus leaves were found to be good binders producing briquettes with good combustion behaviour. The developed loose biomass briquettes were tested for moisture content, energy content and combustion behaviour and were found to be adequate for domestic cooking and heating requirements.
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Effect of HHO on four stroke petrol engine performance

- Madyira, Daniel M., Harding, Wayne G.

  • Authors: Madyira, Daniel M. , Harding, Wayne G.
  • Date: 2014
  • Subjects: Hydrogen gas , Spark ignition , Internal combustion engines , Greenhouse gas emissions
  • Type: Article
  • Identifier: uj:4774 , http://hdl.handle.net/10210/11957
  • Description: Contemporary research into alternative sources of energy for transportation focuses mainly on electric/battery, hybrid and hydrogen powered vehicles. Such focus assumes that the current technology has to be discarded and cannot be improved. However, it is possible to introduce interim technology to alleviate the current challenges arising from continued reliance on fossil fuels. Such challenges include increased greenhouse gas (GHG) emissions with consequent global warming and climate change impacts. The purpose of this research work is to determine if the partial inclusion of hydrogen gas (HHO) in a petrol fuelled spark ignition (SI) internal combustion (IC) engine would improve engine performance. If this is possible, old SI technology can be modified to reduce GHG emissions and improve utilisation of fossil fuels which are expected to dominate the transport energy source for at least the next half century. An HHO generator was designed, constructed and mounted in the engine compartment of a 1989 Ford Laser vehicle. This system allowed partial inclusion of HHO gas on demand into the combustion process through the air supply stream. Detailed and comprehensive experimental investigations were conducted for engine speeds ranging from 1000 to 3500 rpm while parameters such as the power output, exhaust gas emissions and fuel consumption were monitored. Results obtained indicated a decrease in hydrocarbon emissions and an increase in power output with an increase in the HHO gas for certain engine operating conditions. However, performance improvement cannot be claimed for all operating conditions, especially under higher loads where the engine ran with a rich fuel mixture. Hence, further work is required, through HHO generator refinement alongside better engine management, to improve the experimental performance and hence further understanding of this technology.
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Effect of HHO on four stroke petrol engine performance

- Madyira, Daniel M., Harding, Wayne G.

  • Authors: Madyira, Daniel M. , Harding, Wayne G.
  • Date: 2014
  • Subjects: Hydrogen as fuel , Alternative fuel vehicles , Environmental responsibility
  • Type: Article
  • Identifier: uj:6150 , http://hdl.handle.net/10210/13711
  • Description: Contemporary research into alternative sources of energy for transportation focuses mainly on electric/battery, hybrid and hydrogen powered vehicles. Such focus assumes that the current technology has to be discarded and cannot be improved. However, it is possible to introduce interim technology to alleviate the current challenges arising from continued reliance on fossil fuels. Such challenges include increased greenhouse gas (GHG) emissions with consequent global warming and climate change impacts. The purpose of this research work is to determine if the partial inclusion of hydrogen gas (HHO) in a petrol fuelled spark ignition (SI) internal combustion (IC) engine would improve engine performance. If this is possible, old SI technology can be modified to reduce GHG emissions and improve utilisation of fossil fuels which are expected to dominate the transport energy source for at least the next half century. An HHO generator was designed, constructed and mounted in the engine compartment of a 1989 Ford Laser vehicle. This system allowed partial inclusion of HHO gas on demand into the combustion process through the air supply stream. Detailed and comprehensive experimental investigations were conducted for engine speeds ranging from 1000 to 3500 rpm while parameters such as the power output, exhaust gas emissions and fuel consumption were monitored. Results obtained indicated a decrease in hydrocarbon emissions and an increase in power output with an increase in the HHO gas for certain engine operating conditions. However, performance improvement cannot be claimed for all operating conditions, especially under higher loads where the engine ran with a rich fuel mixture. Hence, further work is required, through HHO generator refinement alongside better engine management, to improve the experimental performance and hence further understanding of this technology.
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Effect of plunge depth on weld integrity of friction stir welds of dissimilar aluminium and copper

- Ewuola, Oluwatoyin O., Akinlabi, Esther Titilayo, Madyira, Daniel M.

Effect of wire EDM on microstructure and fracture toughness of 7075-t6511 aluminum alloy

- Madyira, Daniel M.

  • Authors: Madyira, Daniel M.
  • Date: 2016
  • Subjects: Wire EDM , Compact tension specimen , Fracture toughness
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92015 , uj:20175 , Citation: Madyira, D.M. 2016. Effect of wire EDM on microstructure and fracture toughness of 7075-t6511 aluminum alloy.
  • Description: Abstract: This paper reports on an investigation conducted to establish the influence of Wire Electrical Discharge Machining (WEDM) on the fracture toughness of aluminum 7075-T6511. The main objective was to determine if WEDM can be used to introduce a pre-crack into a compact tension specimen instead of the ASTM E-1820-11 specified fatigue pre-crack method. Fracture tests were conducted on four specimens which were pre-cracked using the WEDM technique. The rest of the fracture toughness evaluation followed the ASTM E-1820-11 guidelines. Results obtained from the experimental data were found to be inconsistent with the theoretical expectations. The fracture toughness was found to be significantly dependent on the effect of the WEDM on the material. The WEDM introduced a Heat Affected Zone (HAZ) on the surface of the pre-crack which modifies the fracture behavior of the material. It was concluded that WEDM is not a viable alternative to create a pre-crack in a compact tension specimen to perform fracture toughness testing of aluminum 7075-T6511.
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Effects of wire electrical discharge machining on fracture toughness of grade 5 titanium alloy

- Madyira, Daniel M., Akinlabi, Esther Titilayo

  • Authors: Madyira, Daniel M. , Akinlabi, Esther Titilayo
  • Date: 2014
  • Subjects: Titanium alloys , Electrical discharge machining , Fracture toughness , Compact tension
  • Type: Article
  • Identifier: uj:4752 , ISSN 2078-0958 , http://hdl.handle.net/10210/11738
  • Description: Grade 5 titanium (Ti6Al4V) is considered as the workhorse material when it comes to automotive and aerospace applications. It is widely referred to as an aerospace alloy and is relatively a new engineering material. The main attraction of this material is its high strength to weight ratio when compared to such common engineering materials such as steel and aluminum alloys. One of the major challenges in the use of this aerospace material is its machinability. Its high strength which is maintained at elevated temperatures, low thermal conductivity, low elastic modulus and high reactivity with oxygen is a perfect recipe for machining challenges. This leads to high tool wear and long production times. Such challenges are sometimes overcome by electrical discharge machining (EDM). Given that titanium is usually applied to mission critical components (gears, shafts, wing sections), it is important to understand the possible effect of wire EDM on their structural performance. One of the structural integrity indicators in such applications is fracture toughness. Fracture toughness is widely used for damage tolerance analysis of aerospace components in which critical crack sizes are computed for given loading conditions to arrive at safe inspection and maintenance intervals. It is therefore the purpose of this paper to conduct a study on the effect of wire EDM on the fracture toughness of this aerospace material. Standard test procedure using compact tension (CT) specimen is used to measure the fracture toughness. Four specimens are produced using wire EDM. This includes the pre-crack which is usually produced by fatigue cycling. Obtained results indicate a slight decrease in fracture toughness compared to that reported in literature. In addition, it can also be concluded that wire EDM can be used as an alternative to fatigue pre-cracking in fracture toughness testing of titanium alloys.
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Emissions Comparison of loose biomass briquettes with cow dung and cactus binders

- Shuma, Reuben, Madyira, Daniel M.

Emissions testing of loose biomass in Limpopo province of South Africa

- Shuma, Mikateko R., Madyira, Daniel M., Oosthuizen, Gert A.

Energy content and combustion behaviour of loose biomass available in Limpopo

- Shuma, Rueben M., Madyira, Daniel M., Makonese, Tafadzwa, Oosthuizen, Gert A.

  • Authors: Shuma, Rueben M. , Madyira, Daniel M. , Makonese, Tafadzwa , Oosthuizen, Gert A.
  • Date: 2015-03-31
  • Subjects: Renewable energy , Solid biomass , Combustion
  • Type: Article
  • Identifier: uj:5150 , ISBN 9781479979127 , http://hdl.handle.net/10210/14220
  • Description: Solid biomass continues to be the primary energy source for a significant proportion of Sub-Saharan African society. It is estimated that 80% of energy for heating and cooking in this subcontinent is derived from round wood biomass resulting in estimated annual rate of deforestation of 0.7%. This is unsustainable. This is despite the existence of a substantial resource of loose biomass (forest and agricultural residues) that is produced and disposed of annually. However, one major challenge in harnessing loose biomass as a source of energy is low energy density and poor combustion behaviour. Biomass briquetting technologies can be deployed to improve energy density and combustion behaviour of loose biomass. This requires understanding of the energy content in locally available loose biomass sources. This paper investigates the calorific values (energy content) and combustion behaviour of loose biomass collected from a region in the Limpopo Province of South Africa. The aim of the investigation is to understand the energy value and hence viability of using such loose biomass with the overall goal of developing recipes for biomass briquetting in the region. Calorific values were measured for 12 samples of loose biomass and their combustion behaviour analysed. Certain loose biomass sources are then identified as potential briquetting candidates.
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Energy content and combustion behaviour of loose biomass available in Limpopo

- Shuma, Reuben M., Madyira, Daniel M., Makonese, Tafadzwa N., Oosthuizen, Gert A.

  • Authors: Shuma, Reuben M. , Madyira, Daniel M. , Makonese, Tafadzwa N. , Oosthuizen, Gert A.
  • Date: 2016
  • Subjects: Renewable energy , Solid biomass , Loose biomass
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92337 , uj:20217 , Citation: Shuma, R.M. et al. 2016. Energy content and combustion behaviour of loose biomass available in Limpopo.
  • Description: Abstract: - Solid biomass continues to be the primary energy source for a significant proportion of Sub-Saharan African society. It is estimated that 80% of energy for heating and cooking in this subcontinent is derived from round wood biomass resulting in estimated annual rate of deforestation of 0.7%. This is unsustainable. This is despite the existence of a substantial resource of loose biomass (forest and agricultural residues) that is produced and disposed of annually. However, one major challenge in harnessing loose biomass as a source of energy is low energy density and poor combustion behaviour. Biomass briquetting technologies can be deployed to improve energy density and combustion behaviour of loose biomass . This requires understanding of the energy content in locally available loose biomass sources. This paper investigates the calorific values (energy content) and combustion behaviour of loose biomass collected from a region in the Limpopo Province of South Africa. The aim of the investigation is to understand the energy value and hence viability of using such loose biomass with the overall goal of developing recipes for biomass briquetting in the region . Calorific values were measured for 12 samples of loose biomass and their combustion behaviour analysed. Certain loose biomass sources are then identified as potential briquetting candidates .
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Experimental and numerical analysis of load transfer over a steel composite bonded joint

- Hluyo, Munyaradzi, Madyira, Daniel M., Janse van Rensburg, Nickey, Hurter, Warren

  • Authors: Hluyo, Munyaradzi , Madyira, Daniel M. , Janse van Rensburg, Nickey , Hurter, Warren
  • Date: 2016
  • Subjects: Carbon fibre composites , Adhesive bonded joint , Load transfer
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92090 , uj:20185 , Citation: Hluyo, M. et al. 2016. Experimental and numerical analysis of load transfer over a steel composite bonded joint.
  • Description: Abstract: The current quest for low weight structures has led to a significant increase in the use of adhesive bonded joints more so for applications involving fibre reinforced composite materials. Adhesive bonded joints have major advantages over conventional joining methods such as riveting and bolting; and the nature of composite materials precludes use of other conventional methods such as welding, brazing and soldering. These advantages include lower structural weight due to lower density of the adhesive compared to traditional structural joining materials, lower fabrication costs, resistance to environmental degradation, better aesthetic appeal, lower stress concentrations, noise and vibration isolation capabilities and relative ease of use. Incorporating adhesive bonded joints into mechanical component design requires a higher level of understanding of adhesive joint behaviour. In particular it is important to understand the load transfer and joint failure mechanisms operative in the adhesive bonded joints. A lot of design information is available on conventional joining methods while information on design of bonded joints remains restricted to specialised applications such as automotive and aerospace . The aim of this paper is to investigate the effect of bond thickness on the load transfer between a steel insert and tubular glass fibre reinforced composite component under axial loading. A finite element analysis model is developed to analyse the behaviour of the joint . The model is validated using experimentally measured tensile response data for a selected insert length and adhesive layer thickness . The obtained results show the close relationship between the load transfer distances with adhesive elastic modulus. Furthermore the stress distribution along the adhesive bond layer was found to be independent of adhesive layer thickness. Adhesive layer thickness also has insignificant contribution to stress levels and load transfer distance.
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