Measurements of flow phenomena induced by suction through perforated and partially plugged surfaces

Efforts were directed towards completing construction of the windtunnel test section, assembling instrumentation, programming the data acquisition and reduction system, adjusting the streamwise pressure gradient of the test section, calibrating the hot-wire anemometer probe, and constructing and testing a smoke generator. The test section was installed in the wind tunnel and is completely operational. The streamwise pressure gradient was adjusted to be nominally zero at a free-stream velocity of 3.05 m/s (10 ft/s). This was accomplished by adjusting the upper wall of the test section to be slightly divergent. The change in static pressure between any two streamwise locations in the test section was less than one percent of the free-stream dynamic pressure. A suitable means was found for accurately calibrating the hot-wire probe which is used to measure boundary-layer velocity profiles and fluctuating velocities

Experimental study of flow due to an isolated suction hole and a partially plugged suction slot

Details for construction of a model of a partially plugged, laminar flow control, suction slot and an isolated hole are presented. The experimental wind tunnel facility and instrumentation is described. Preliminary boundary layer velocity profiles (without suction model) are presented and shown to be in good agreement with the Blasius laminar profile. Recommendations for the completion of the study are made. An experimental program for study of transition on a rotating disk is described along with preliminary disturbance amplification rate data

Reduced-order urban wind interference

A novel approach is demonstrated to approximate the effects of complex urban interference on the wind-induced surface pressure of tall buildings. This is achieved by decomposition of the domain into two components: the obstruction model (OM) of the static large-scale urban context, for which a single computational fluid dynamics (CFD) simulation is run; and the principal model (PM) of the isolated tall building under design, for which repeatable reduced-order model (ROM) predictions can be made. The ROM is generated with an artificial neural network (ANN), using a set of feature vectors comprising an input of local shape descriptors and a range of wind speeds from a training geometry, and an output response of pressure. For testing, the OM CFD simulation provides the flow boundary condition wind speeds to the PM ROM prediction. The result is vertex-resolution surface pressure data for the PM mesh, intended for use within generative design exploration and optimisation. It is found that the mean absolute prediction error is around 5.0% (σ: 7.8%) with an on-line process time of 390 s, 27 times faster than conventional CFD simulation; considering full process time, only 3.2 design iterations are required for the ROM time to match CFD. Existing work in the literature focuses solely on creating generalised rules relating global configuration parameters and a global interference factor (IF). The work presented here is therefore a significantly alternative approach, with the advantages of increased geometric flexibility, output resolution, speed, and accuracy

The emergence of the global workplace : opportunities and barriers for building surveyors in Oceania

The Royal Institution of Chartered Surveyors (RICS) the professional body representing surveyors in the UK, has implemented a policy to globalise in order to meet the challenges and opportunities the global marketplace was creating for its members as well as protecting and serving its interests (RICS, 1999). Quantity surveyors had a presence and history of employment outside the UK, particularly in the Middle and Far East. Real estate surveyors found the transition to working in European Union (EU) countries relatively straightforward and numerous UK real estate organisations have European, Asian, North American and Oceanic offices. Additionally UK based firms establishing partnerships with overseas real estate firms expanded significantly over the previous decade. Building Surveying is different. Small numbers worked in commonwealth countries but in most countries their professional and academic qualifications were not recognised. With the changes implemented by the RICS, this paper examines the barriers and opportunities facing RICS Chartered Building Surveyors (CBS) in Oceania (taken as Australia, New Zealand, Papua New Guinea and Fiji).A desk top study reviewed the political, economic and sociological variables affecting employment opportunities and professional services which were put to the RICS Oceania Building Surveying Faculty. No previous study had been undertaken to identify the specific barriers and opportunities in Oceania for the BS and this research adopted a census survey of RICS practitioners currently employed in the region and the results form the most comprehensive picture of the current position. The findings are that some of the opportunities and barriers will change in significance over time. The main barriers to growth were perceived as lack of support from a Euro focussed RICS and the difficulties associated with being perceived as outsiders. Opportunities were perceived as emerging in new areas of professional services such as sustainability and energy efficiency.<br /

Building surveyors in Australia : an emerging profession

Australian and UK Building Codes undergo revision to improve the health and safety standards in the built environment and reflect wider social and technological changes. In the 1990s both countries changed to the option for designers to provide alternative solutions, where designers provide calculations to demonstrate that the codes are satisfied but not through the traditional deemed to satisfy route. Other social and legislative changes have had an impact on the profession. In the UK the Institute of Building Control, the equivalent of the Australian Institute of Building Surveyors responded by joining the Royal Institution of the Chartered Surveyors. Thus it has become part of the largest surveying professional body, what does that mean for the profession? This paper compares the Australian and UK professions and looks at some of the issues affecting their future direction.<br /

Office buildings and the environment : the increasing role of facility managers

The Australian commercial stock emits 12% of all greenhouse gas emissions however the commercial property market has some inherent barriers to sustainability (DSE, 2005). A substantial proportion of the stock is owned by institutional investors who are unconvinced by the need to improve their stock and pass on running costs to tenants (Callender &amp; Key, 1997). The links between the built environment and sustainability issues such as fossil fuel consumption and climate change is clear. In developed countries buildings contribute around half of all carbon dioxide emissions and offer considerable scope for a significant contribution to sustainability through ecologically aware design and increased energy efficiency (BRE, 1996). As capital values are not greatly affected by sustainability, owners react by doing little or nothing and the effect is to limit sustainability-related investment and undermine efforts to deliver sustainability in the sector. Facility managers are in an influential position to help address sustainability issues via an increased awareness of energy efficiency and CO2 emissions.Even though the efficiency of buildings is primarily focused on new stock, with an existing churn replacement rate of approximately 2-3% the existing stock must be improved if urban built environment greenhouse gas emissions are to be reduced &ndash; clearly the management of existing stock must therefore contribute to substantial savings in energy use. Much of the property and surveying research has previously adopted an illustrative case study approach advocating the benefits of ESD and energy efficiency in existing buildings. This research adopts a radically different approach and profiles the entire office stock of a global CBD, namely Melbourne, which is seeking to become a carbon neutral city by 2020 (City of Melbourne, 2003). The research also employs scenario forecasting to model future changes to the stock over a fifteen year period. This paper sets out the rationale for the research and establishes the methodological approach adopted by the research team. The results provides a unique insight into the variations between different building types and grades of office buildings, which in turn will allow facility managers to gain a better understanding of where gains in energy efficiency can be made.<br /

The structural and behaviourial barriers to sustainable real estate development

Sustainable real estate development appears, on literal translation of both terms, to be an oxymoron - however it is a concept that the real estate profession needs to embrace knowledgably. On one hand it can be argued that real estate development is required for continued economic growth and the adoption of sustainability measures is required to mitigate climate change and global warming. Over the last few years there has been growth in the number of sustainability tools available to designers and operators of buildings. For example, in the US the LEED scheme enables designers to assess the environmental impact of their design and to benchmark the sustainability of the design against industry recognised criteria. LEED follows a similar format to the UK&rsquo;s Building Research Establishment Environmental Assessment Method (BREEAM) introduced in 1990 and the Australian &lsquo;GreenStar&rsquo; introduced in 2004. Even though there are an increasing number of sustainability tools available to designers, it still remains that the degree of uptake of the tools has been sporadic. This paper discusses the barriers to sustainable real estate development. Firstly it identifies the barriers to uptake and secondly it establishes the structural barriers in the market which prevent the wider uptake of tools.<br /