R&D Journals for 2010 - Volume 26.
How to use the R&D Journal File Library: File Some files are large (in excess of 2MB) and may take some time to download. Scroll down to find the specific paper you seek. Click on the 'more' link to view the full title, abstract and authors. If you are not sure of the title of the paper you are searching for, try the ‘community search’ button on the top left corner of this page. Enter a keyword then select search. If the keyword you use is in the abstract, all papers that contain this keyword will show in the results of your search.
|
A Review of the Machinability of Titanium Alloys
PDF (565.78 KB)
[ more ]
[ hide ]
|
|
2010/12/10
|
TITLE: A Review of the Machinability of Titanium Alloys
AUTHORS: G.A. Oosthuizen, G. Akdogan, D. Dimitrov, N.F. Treurnicht
DATE PUBLISHED: December 2010
ABSTRACT: Titanium alloys find wide application in many industries, due to their unrivalled and unique
combination of high strength-to-weight ratio and high resistance to corrosion. The machinability of titanium alloys is impaired by their high temperature chemical reactivity, low thermal conductivity and low modulus of elasticity. In this paper, the machining fundamentals specific to titanium alloys are presented and the machining of Ti6Al4V with conventional and advanced cutting tool materials is reviewed. The experimental results from several sources are discussed and form the basis of a collaborative research project between academia and industry. The selected aerospace benchmark component is presented and milling strategies for machining performance enhancement are discussed.
|
|
Auto-ignition prediction during hot start conditio
PDF (130.54 KB)
[ more ]
[ hide ]
|
|
2010/12/10
|
TITLE: Auto-ignition prediction during hot start conditions
AUTHOR: J. Wodausch, J. Momberg, J. Roux H. Holdack-Janssen and T. van Niekerk
DATE PUBLISHED: December 2010
ABSTRACT: This paper describes the development of an empirical thermodynamic single-zone model to predict auto-ignition in an internal combustion engine. In this case the development basis is a 1.4 L multi port
injection (MPI) internal combustion engine. A model was created to calculate the probability of auto-ignition with regards to the engine design, thermodynamic laws and the carburetion of the air-fuel mixture. The theoretical model developed was verified with measurements. Adequate correlation between the predicted and measured probability results was obtained.
Additional Keywords: Knock detection modelling.
|
|
Developing a Low-cost Seven Degree of Freedom
PDF (422.31 KB)
[ more ]
[ hide ]
|
|
2010/11/22
|
TITLE: Developing a Low-cost Seven Degree of Freedom Minimally Invasive Surgical Manipulator
AUTHORS: P.J. Christiane, K. Schreve and C. Scheffer
DATE PUBLISHED: 22 Nov 2010
ABSTRACT: Minimally invasive surgery (MIS) gives surgeons the ability to operate through a few small incisions made in the patient’s body. Through these incisions, long rigid instruments are placed into the body and manipulated to perform the necessary surgical tasks. Conventional instruments are constrained, however, through having only five degrees of freedom (DOF), as well as having scaled and mirrored movements, thereby limiting the surgeon’s dexterity. Surgeons are also deprived of depth perception and hand-eye coordination through having only two-dimensional visual feedback. Surgical robotics attempt to alleviate these drawbacks by increasing the dexterity, eliminating the fulcrum effect and providing the surgeon with three-dimensional visualisation...
|
|
Engineering Principles and Medical Discoveries
PDF (525.7 KB)
[ more ]
[ hide ]
|
|
2010/11/22
|
TITLE: Engineering Principles and Medical Discoveries
AUTHOR: E.H. Mathew and L. Liebenberg
DATE PUBLISHED: 22 Nov 10
ABSTRACT: Engineering researchers often tackle problems slightly differently from medical researchers. Engineers usually try to model a phenomenon and then test its validity. Medical researchers on the other hand usually do large empirical studies and derive models from the statistical analyses. In this paper we show the value of the engineering approach as applied to the problem of carbohydrate (CHO) metabolism into blood glucose in the body. We show that the engineering approach leads to a more acceptable description than the one currently used for food labelling. It is also more practical than other detailed attempts to solve the historical problem. The CHO metabolism model is used to simulate the full blood glucose cycle, using engineering equivalents. Correct modelling of this cycle is valuable as blood glucose inter alia influences cancer, cardiovascular...
|
|
Fuel Consumption for Conventional & Electrically..
PDF (309.41 KB)
[ more ]
[ hide ]
|
|
2010/08/24
|
TITLE: Fuel Consumption for Conventional & Electrically Driven AC Compressors
AUTHORS: C. Marais, H. Holdack-Janssen and T. van Niekerk
DATE PUBLISHED: 2 June 2010
ABSTRACT: The emergence of hybrid vehicle technology also sparked the development of different electrical systems that were made viable by the higher onboard voltage systems employed in hybrid vehicles. One of these developments is the electrical air conditioning
compressor for use in automobile applications. The question arises whether it would be feasible and sensible to employ an electrical air conditioning system in conventional combustion engine vehicles from an overall fuel consumption and vehicle emissions point of view. This study attempts to answer this question by making use of simulation tools to represent an average combustion engine vehicle. The simulation is constructed in such a way that it is possible to simulate the vehicle without an air conditioning system and then provides the opportunity to...
|
|
Development of a Thermal Energy Storage for the I
PDF (574.34 KB)
[ more ]
[ hide ]
|
|
2010/06/15
|
TITLE: Development of a Thermal Energy Storage for the Integration Solar Energy Project
AUTHORS: S.A. Sulaiman and F.L. Inambao
DATE PUBLISHED: 31 May 2010
ABSTRACT: Large percentages of the South African population have no access to grid power and are located at distances that make provision for such facility uneconomical. Also traditional fuels are under pressure. Most areas in South Africa receive 300 days of sunshine per year. The proposed solar system addresses the needs of such communities.
The main objective of the paper is the development of a solar thermal energy storage system utilizing phase change material (PCM). The system allows for sensible heat storage as well as latent heat storage using PCM, which melts at sufficiently high temperatures for cooking a variety of food types. The right choice of a suitable PCM to take advantage of the latent heat absorbed during phase changes is important. The system can overcome the time mismatch between solar available...
|
|
Performance Evaluation of Aluminium Alloy 7075
PDF (563.17 KB)
[ more ]
[ hide ]
|
|
2010/06/15
|
TITLE: Performance Evaluation of Aluminium Alloy 7075 for Use in Tool Design for the Plastics Industry
AUTHORS: A.G. Buys, V. Cain and R.D. Knutsen
PUBLISHED: 1/2/2010
ABSTRACT: The performance of a high-strength aluminium alloy AA7075 as a candidate injection mould material has been assessed. Particular attention has been focused on the thermal and wear performance of the AA7075 alloy compared to a standard EN19 tool steel alloy. In view of the fact that aluminium often fails due to poor wear resistance, surface treatment of the aluminium alloy was implemented by hard anodising. The assessment was performed by manufacturing three mould insert sets of identical design from each of the materials, namely EN19 steel, AA7075 and AA7075 in the hard anodised state. Each insert set was subjected to 10 000 shots in an injection moulding machine. The core temperature of the inserts was measured during moulding and wear was assessed by comparing profile measurements of the mould cavities...
|
|
An Evaluation of Simplified Methods to Model the p
PDF (587.99 KB)
[ more ]
[ hide ]
|
|
2010/11/22
|
FULL TITLE: An Evaluation of Simplified Methods to Model the performance of Axial Flow Fan Arrays
AUTHORS: S.J. van der Spuy, T.W. von Backström and D.G. Kröger
DATE PUBLISHED: 7 June 2010
ABSTRACT: This paper investigates two simplified methods to model axial flow fans in a multiple fan operating environment using computational fluid dynamics. . The application of the two methods are explained and illustrated, after which they are applied to a multiple fan CFD model. The CFD results are compared to experimental results to illustrate the applicability of the methods. It is concluded that the simplified presentation of an axial flow fan is particularly helpful in predicting the system volumetric effectiveness of multiple fan installations subjected to adverse inlet flow conditions, particularly during windy periods.
|
