Browsing by Author "Palmer, Duncan"

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    The development of a biofuels engine testing facility
    (Stellenbosch : Stellenbosch University, 2008-12) Palmer, Duncan; Lorenzen, L.; Van der Spuy, Johan; Stellenbosch University. Faculty of Engineering. Dept. of Process Engineering.; Stellenbosch University. Faculty of Engineering. Dept. of Mechanical and Mechatronic Engineering.
    This report covers the development of a biofuels engine testing facility at Stellenbosch University. The motivation for the project was three fold: a) a desire to establish biofuels and engine testing know-how; b) to test the performance characteristics of biodiesel; and c) make a facility available for future research. The two main conclusions drawn from the initial test results are: 1) the test cell is fully operational and 2) biodiesel can be substituted for mineral diesel. To the author’s knowledge this is the first biofuel specific engine testing facility in South Africa. After a literature study the test cell was realised in three phases. • Firstly, the hardware layout was designed and the necessary equipment was sourced from respectable suppliers including the judicious use of good qaulity second hand components to minimize capital cost. • The test cell was then instrumented with new sensors. Key components among these are the K-type thermocouples, barometric pressure, humidity, oil pressure and an Allen-Bradley programmable controller to serve as a data acquisition card. Two software programs were chosen, ETA for the control of the test cell and RSLogix to program the programmable logic controller (PLC). • The complete system was then integrated, debugged and validated. The design methods and procedures have been documented throughout the project along with user manuals to facilitate further research. To determine the difference in combustion parameters between biodiesel and mineral diesel an autonomous power curve test was conducted. This revealed little difference in terms of performance between the two fuels, although biodiesel had on average a marginal 0.4% decrease in power over mineral diesel. The fuel consumption for pure biodiesel was found to be higher, which is as expected as it is has a lower calorific value than mineral diesel. As a final validation, an energy balance was conducted. Here the calculated calorific value of biodiesel was compared to the results from a calorie bomb test, and the two results were found to be within 2% of each of other.
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    The financial survival probability of living annuitants
    (AOSIS, 2013) Palmer, Duncan; Krige, Niel
    This study addresses the question of how long a given amount of capital will be able to fund a living annuitant if the following five parameters are known: expected retirement duration (i.e. years between date of retirement and date of death), return on investment, inflation, annual withdrawal amount and initial capital amount available. A model (the Pension Model) that graphically depicts the relationship between these parameters was developed. This model facilitates retirement planning by showing how retirement duration and withdrawal rates change the financial “Survival Probability” (SP), which is the probability of having enough capital to maintain a desired withdrawal rate for the expected retirement duration. The underlying model is based on long-term historical investment yields of equities, bonds and cash in South Africa using Monte Carlo simulation with Cholesky factorisation.
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    Real age-adjusted life expectancy
    (University of Johannesburg, 2013) Palmer, Duncan; Krige, Niel
    This study summarises the development of a model to determine an individual’s adjusted life expectancy based on his Real Age. The model incorporates aspects such as gender, residing province, income, HIV status, ethnic background, weight, exercise, family illness history, stress, substance abuse and diet. Predicting life expectancy is vital in retirement planning for two reasons: 1) given the diverse nature of South Africa, the national average life expectancy cannot be applied to everyone; and 2) retirement duration forms a vital part in the retirement planning process. Retirees can make more informed financial investment decisions based on their Real Age, thus increasing the probability of having sufficient funds during retirement. Three representative examples of South African Real Age-adjusted life expectancies were simulated, predicting life expectancies of 67, 72 and 87 years, notably different from the 50 year average South African life expectancy.