Condition monitoring wind turbine gearboxes using on-line/in-line oil analysis techniques

Paper examining condition monitoring wind turbine gearboxes using on-line/in-line oil analysis techniques

Efficient use of energy

World energy demand is projected to grow by more than 50% by 2030.[21] Improving energy efficiency is one of the most economical and short to medium term ways Scotland can reduce its dependence on fossil fuels and reduce its emissions of greenhouse gases. Transportation and buildings, which account for two thirds of energy usage [16], consume far more than they need to, but even though there are many affordable energy efficient technologies that can save consumers money, current utilisation is small. To overcome this, the government must adopt policies that invest in research and development programs that target energy efficiency. Incentives schemes if properly implemented can stimulate and encourage energy efficiency which is one of Scotland's great hidden energy opportunities. This paper outlines the position of the Institution of Engineers and Shipbuilders in Scotland and makes recommendations for the Scottish Government by two separate means of improving energy efficiency; reducing wastage and providing the same end need using less energy

Development of a regenerative pump impeller using rapid manufacturing techniques

This paper presents a method of rapid manufacture used in the development of a regenerative pump impeller. Rapid manufacturing technology was used to create complex impeller blade profiles for testing as part of a regenerative pump optimisation process. Regenerative pumps are the subject of increased interest in industry. Ten modified impeller blade profiles, relative to the standard radial configuration, were evaluated with the use of computational fluid dynamics and experimental testing. Prototype impellers were needed for experimental validation of the CFD results. The manufacture of the complex blade profiles, using conventional milling techniques, is a considerable challenge for skilled machinists. The complexity of the modified blade profiles would normally necessitate the use of expensive CNC machining with 5 asis capability. With an impeller less than 75mm in diameter and a maximum blade thickness of 1.3mm, a rapid manufacturing technique enabled production of complex blade profiles that were dimensionally accurate and structurally robust enough for testing. As more advanced rapid prototyping machines become available in the study in the future, e.g. 3D photopolymer jetting machine, the quality of the parts, particularly in terms of surface finish, will improve and the amount of post processing operations will reduce. This technique offers the possibility to produce components of increased complexity whilst ensuring quality, strength, performance and speed of manufacture. The ability to manufacture complex blade profiles that are robust enough for testing, in a rapid and cost effective manner is proving essential in the overall design optimisation process for the pump

Design study of a regenerative pump using one-dimensional and three-dimensional numerical techniques

Regenerative pumps are low cost, compact, able to deliver high heads at low flow rates. Furthermore with stable performance characteristics they can operate with very small NPSH. The complexity of the flow field is a serious challenge for any kind of mathematical modelling. This paper compares an analytical and numerical technique of resolving the performance for a new regenerative pump design. The performance characteristics computed by a CFD approach and a new one-dimensional model are compared and matched to experimental test results. The approaches of both modelling techniques are assessed as potential design tools. The approaches are shown to not only successfully resolve the complex flow field within the pump; the CFD is also capable of resolving local flow properties to conduct further refinements. The flow field is represented by the CFD as it has never been before. A new design process is suggested. The new regenerative pump design is considered with a comparable duty centrifugal pump, proving that for many high head low flow rate applications the regenerative pump is a better choice

Numerical and experimental design study of a regenerative pump

This paper presents the use of a commercial CFD code to simulate the flow-field within the regenerative pump and compare the CFD results with new experimental data. Regenerative pumps are the subject of increased interest in industry as these pumps are low cost, low specific speed, compact and able to deliver high heads with stable performance characteristics. The complex flow-field within the regenerative pump represents a considerable challenge to detailed mathematical modelling. This paper also presents a novel rapid manufacturing process used to consider the effect of impeller geometry changes on the pump efficiency. Ten modified impeller blade profiles, relative to a standard radial configuration, were evaluated. The CFD performance results demonstrate reasonable agreement with the experimental tests. The CFD results also demonstrate that it is possible to represent the helical flow field for the pump which has been witnessed only in experimental flow visualisation until now. The ability to use CFD modelling in conjunction with rapid manufacturing techniques has meant that more complex impeller geometry configurations can now be assessed with better understanding of the flow-field and resulting efficiency

Design study of a novel regenerative pump using experimental and numerical techniques

This paper presents a numerical and experimental analysis of a new regenerative pump design. The complex flow-field within regenerative pumps represents a significant challenge to previous published mathematical models. The new pump design incorporates a new axial inlet and outlet port. The experimental and numerical results demonstrate that it is not only possible to resolve the flowfield for this pump type but also demonstrates this pump as a viable alternative to other kinetic rotodynamic machines. The use of the latest rapid manufacturing techniques have enabled the production of the complex geometry of the axial ports required for the new configuration

Reforming Christianity by Reforming Christians: Devotional Writings of the Late Medieval and Reformation Era

During the late medieval and Reformation era in Europe, a series of Christian devotional works were created that stressed a deeper personal relationship with Christ, rather than ritual and public devotion alone. These works span the time period from the early fifteenth century through the early seventeenth century and prepared the way for and shaped the Protestant and Roman Catholic reformations alike. The devotional works addressed here were created in the quest for reform, of both the individual and the Church. This occurred as the importance of developing a better relationship with Jesus was taking on a new urgency for both pre-Reformation and post-Reformation Catholics as well as for Protestants. For all denominations an important social common denominator was the emergence of a larger group of educated, literate laity confronting very difficult times. In the end, Latin Christianity would not survive the new approaches to Christianity intact, although varying branches of Christianity would find the reform and direction they craved—albeit at the price of religious and cultural unity that continues to influence (and trouble) European civilization to this day

The Effectiveness of Aeration and Potassium Permanganate Oxidation and Filtration on Removal of Iron and Manganese from Ground Water

The United States Public Health Service (USPHS) established water quality standards in 1946 and revised them in 1956 and 1962. In these standards the maximum recommended concentrations of iron and manganese were 0.03 and 0.05 mg/l respectively. Because trace amounts of these elements are essential for proper nutrition of both plants and animals, the recommended limits are not based on any physiological or environmental considerations. Rather, the presence of iron and manganese in water is objectional because the precipitation of these metals alters the appearance of the water, turning it a turbid yellow brown to black. The Brookings, South Dakota East Water Treatment Plant is primarily an iron and manganese removal plant. Present operation of the facility includes aeration, lime softening, alum coagulation, re-carbonation, potassium permanganate oxidation, filtration, chlorination and fluoridation. Iron and manganese in the plant effluent are within the USPHS recommended standards. The purpose of this investigation was to determine if comparable iron and manganese removal can be achieved using only aeration, potassium permanganate oxidation and filtration. In this investigation, removal efficiencies and water stability were used as parameters of comparison. A pilot unit was used in these investigations to avoid disruption of the East Plant operations. This pilot unit was included the same units and filter media as the East Plant and was operated at the same detention times and filter rates. Both the East Plant and pilot unit received raw water from Well 1

Propaganda and the presidency : an analysis of Lyndon B. Johnson's media relations, 1963-1968

Lyndon Johnson's presidency saw a great shift in the balance of domestic politics in the United States. While there was great merit to many of his domestic aspirations the erosion of his own credibility damaged the standing of the Democratic Party and ensured that the Republicans swept back into office in 1968. The Democrats saw only one president - Jimmy Carter - elected between 1968 and 1992 following Johnson's presidency and four of the subsequent five presidents were Republicans; Richard Nixon, Gerald Ford, Ronald Reagan and George H. W. Bush.;The failure of the Great Society and subsequent inflation crisis caused in part by spending on domestic concerns and Vietnam were influential on a general upswing in conservatism, and although it should not be argued that the Johnson administration was wholly responsible for this, there is at least some evidence to suggest that a grassroots rise in conservatism happened under Johnson's watch. The legacy of the administration was to usher in an era of suspicion and mistrust of the presidency, which would ultimately culminate in the Watergate Scandal under his successor Nixon.;Robert Dallek perhaps best summed up the Johnson presidency when he said, 'Whatever impulse future historians may have to pigeonhole Johnson as a near great, average, or failed President, I am confident that a close review of his time in office will leave them reluctant to put a single stamp on his term.' This is certainly true. Johnson is incredibly difficult to categorise as a president, with possibly the best description of his immediate legacy coming from Newsweek columnist Charles Roberts, following his death in 1973:;He leaves office a man whose epitaph will some day defy the confines of even a Texas-size tombstone: the most militant civil-rights advocate ever to occupy the White House, reviled by negro militants; a Southerner scorned by Southerners as a turncoat; a liberal despised by liberals despite the fact he achieved most of what they sought for thirty years; a friend of education rejected by intellectuals; a compromiser who could not compromise a war ten thousand miles away; a consensus-seeker who in the clutch abandoned his consensus rather than his convictions; a power hungry partisan politician who, in the end, shunned power and partisanship to achieve national unity.;There is no question that Lyndon Johnson is an important president, and his achievements with Medicare, civil rights legislation and anti-poverty acts were monumental. His influence on the presidency and politics in the years following his time in office should not be underestimated. What he was not however, was a man who could use the press to his advantage. Johnson presided over an era of changing attitudes and a more open and technologically advanced press than had existed in America prior to the 1960s. As we have seen, he consistently showed a short-term, reactive strategy toward dealing with press coverage and sliding approval ratings, and with each reaction and each ill-thought-out response to political problems, he created further issues for himself as his presidency went on.;This was evident in his planning for the 1964 election, when he positioned himself as the anti-war candidate against Barry Goldwater's hard-line views, even while he knew that escalation in Vietnam was assured. It was apparent in 1965, when James Greenfield criticised the administration for only meeting the crisis of the moment and not looking further ahead. It was clear in 1966, when the press openly reported on the credibility gap between Johnson and the people. By the time the administration took note and conducted what might be termed as a public relations offensive in late 1967, it was too late. In their assessments of how well the country was doing, they failed to look forward and see what reports already told them; the Tet Offensive of January 1968 was already being foreshadowed by enemy actions.;Tet shattered the goodwill that Johnson earned with his most pro-active strategy, and permanently ruined his credibility with the American people. While there is undoubtedly an argument to be made that external circumstances and the political volatility of the 1960s had an effect on how pro-active the president could be in his press dealings, the administration failed to effectively organise a strategy to propagandise the policies of the presidency and ultimately that failure lay chiefly with Lyndon B Johnson, himself.Lyndon Johnson's presidency saw a great shift in the balance of domestic politics in the United States. While there was great merit to many of his domestic aspirations the erosion of his own credibility damaged the standing of the Democratic Party and ensured that the Republicans swept back into office in 1968. The Democrats saw only one president - Jimmy Carter - elected between 1968 and 1992 following Johnson's presidency and four of the subsequent five presidents were Republicans; Richard Nixon, Gerald Ford, Ronald Reagan and George H. W. Bush.;The failure of the Great Society and subsequent inflation crisis caused in part by spending on domestic concerns and Vietnam were influential on a general upswing in conservatism, and although it should not be argued that the Johnson administration was wholly responsible for this, there is at least some evidence to suggest that a grassroots rise in conservatism happened under Johnson's watch. The legacy of the administration was to usher in an era of suspicion and mistrust of the presidency, which would ultimately culminate in the Watergate Scandal under his successor Nixon.;Robert Dallek perhaps best summed up the Johnson presidency when he said, 'Whatever impulse future historians may have to pigeonhole Johnson as a near great, average, or failed President, I am confident that a close review of his time in office will leave them reluctant to put a single stamp on his term.' This is certainly true. Johnson is incredibly difficult to categorise as a president, with possibly the best description of his immediate legacy coming from Newsweek columnist Charles Roberts, following his death in 1973:;He leaves office a man whose epitaph will some day defy the confines of even a Texas-size tombstone: the most militant civil-rights advocate ever to occupy the White House, reviled by negro militants; a Southerner scorned by Southerners as a turncoat; a liberal despised by liberals despite the fact he achieved most of what they sought for thirty years; a friend of education rejected by intellectuals; a compromiser who could not compromise a war ten thousand miles away; a consensus-seeker who in the clutch abandoned his consensus rather than his convictions; a power hungry partisan politician who, in the end, shunned power and partisanship to achieve national unity.;There is no question that Lyndon Johnson is an important president, and his achievements with Medicare, civil rights legislation and anti-poverty acts were monumental. His influence on the presidency and politics in the years following his time in office should not be underestimated. What he was not however, was a man who could use the press to his advantage. Johnson presided over an era of changing attitudes and a more open and technologically advanced press than had existed in America prior to the 1960s. As we have seen, he consistently showed a short-term, reactive strategy toward dealing with press coverage and sliding approval ratings, and with each reaction and each ill-thought-out response to political problems, he created further issues for himself as his presidency went on.;This was evident in his planning for the 1964 election, when he positioned himself as the anti-war candidate against Barry Goldwater's hard-line views, even while he knew that escalation in Vietnam was assured. It was apparent in 1965, when James Greenfield criticised the administration for only meeting the crisis of the moment and not looking further ahead. It was clear in 1966, when the press openly reported on the credibility gap between Johnson and the people. By the time the administration took note and conducted what might be termed as a public relations offensive in late 1967, it was too late. In their assessments of how well the country was doing, they failed to look forward and see what reports already told them; the Tet Offensive of January 1968 was already being foreshadowed by enemy actions.;Tet shattered the goodwill that Johnson earned with his most pro-active strategy, and permanently ruined his credibility with the American people. While there is undoubtedly an argument to be made that external circumstances and the political volatility of the 1960s had an effect on how pro-active the president could be in his press dealings, the administration failed to effectively organise a strategy to propagandise the policies of the presidency and ultimately that failure lay chiefly with Lyndon B Johnson, himself

A one-dimensional numerical model for the momentum exchange in regenerative pumps

The regenerative pump is a rotor-dynamic turbomachine capable of developing high heads at low flow rates and low specific speeds. In spite of their low efficiency, usually less than 50 %, they have found a wide range of applications as compact single-stage pumps with other beneficial features. The potential of a modified regenerative pump design is presented for consideration of the performance improvements. In this paper the fluid dynamic behaviour of the novel design was predicted using a one-dimensional model developed by the authors. Unlike most one-dimensional models previously published for regenerative pumps, the momentum exchange is computed numerically. Previous one-dimensional models relied on experimental data and correction factors; the model presented in this paper demonstrates accurate prediction of the pump performance characteristics without the need for correction with experimental data. The validity of this approach is highlighted by the comparison of computed and measured results for two different regenerative pump standards. The pump performance is assessed numerically without the need of correction factors or other experimental data. This paper presents an approach for regenerative pumps using a physically valid geometry model and by resolving the circulatory velocity in peripheral direction