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A contra-rotating marine current turbine has a number of attractive features: near-zero reactive torque on the support structure, near-zero swirl in the wake, and high relative interrotor rotational speeds. Modified blade element modelling theory has been used to design and predict the characteristics of such a turbine, and a model turbine and test rig have been constructed. Tests in a towing tank demonstrated the feasibility of the concept. Power coefficients were very high for such a small model and in excellent agreement with predictions, confirming the accuracy of the computational modelling procedures.High-frequency blade loading data were obtained in the course of the experiments. These show the anticipated dynamic components for a contra-rotating machine. Flow visualisation of the wake verified the lack of swirl behind the turbine. A larger machine is presently under construction for sea trials.

There is growing concern about the adverse effects of fungal bioaerosols on the occupants of damp dwellings. Based on an extensive analysis of previously published data and on experiments carried out within this study, critical limits for the growth of the indoor fungiEurotium herbariorum, Aspergillus versicolor, and Stachybotrys chartarum were mathematically described in terms of growth limit curves (isopleths) which define the minimum combination of temperature (T) and relative humidity (RH) at which growth will occur. Each growth limit curve was generated from a series of data points on a T-RH plot and mathematically fitted by using a third-order polynomial equation of the form RH =a 3T3 +a 2T2 +a 1T + a 0. This fungal growth prediction model was incorporated within the ESP-r (Environmental Systems Performance [rstands for “research”]) computer-based program for transient simulation of the energy and environmental performance of buildings. For any specified location, the ESP-r system is able to predict the time series evolution of local surface temperature and relative humidity, taking explicit account of constructional moisture flow, moisture generation sources, and air movement. This allows the predicted local conditions to be superimposed directly onto fungal growth curves. The concentration of plotted points relative to the curves allows an assessment of the risk of fungal growth. The system’s predictive capability was tested via laboratory experiments and by comparison with monitored data from a fungus-contaminated house.

The Energy Systems Research Unit within the Department of Mechanical Engineering at the University of Strathclyde has developed a novel contra-rotating tidal turbine (CoRMaT). Novel aspects of this turbine include two contra-rotating sets of rotor blades directly driving an open-to-sea permanent magnet generator. The balancing of reactive forces by the use of contra-rotation enables the use of a single point compliant mooring system for station keeping. A series of tank and sea tests have led to the deployment and demonstration of a small stand-alone next generation tidal turbine. The stability of a single-point mooring system is examined and power quality from the direct drive generator is evaluated. It is noted that good stability from a single point mooring can be achieved within a real tidal stream; however from sea testing of the turbine off the west coast of Scotland in the Sound of Islay, it is shown that some instabilities in device station keeping may have an effect on the output electrical power quality. Finally, the scaling up of the power take-off and delivery options for a 250kW production prototype are described and assessed. It was concluded that the most promising option was an enlarged version of the system already tested, namely a direct-drive contra-rotating permanent magnet generator

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A 2 nd generation, contra-rotating marine current turbine has been developed by the Energy Systems Research Unit at the University of Strathclyde. This system can be tuned to extract energy over a wide range of water depths by "flying" a neutrally-buoyant device from a flexible, tensioned mooring. After successful proof of concept turbine trials, the development programme has moved on to investigate the performance of a scaled prototype system comprising of a dual rotor, contra-rotating turbine directly coupled to a submersible contra-rotating generator; and held on station via a gravity based tensioned mooring system. The turbine/generator assembly was initially tested in a towing tank, before the entire system underwent sea trials initially at the Kyles of Bute in the River Clyde Estuary before being deployed in eth Sound of Islay of eth West Coast of Scotland. An investigation into turbine wake development (an area in which it is hoped that the contra-rotating turbine will have uniquely beneficial properties) has recently begun. Small single-rotor model turbines have been deployed in a flume. Trends observed so far are in accordance with those observed by other researchers.

The area of policy formulation for the energy and carbon performance of buildings is coming under increasing focus. A major challenge is to account for the large variation within building stocks relative to factors such as location, climate, age, construction, previous upgrades, appliance usage, and type of heating/cooling/lighting system. Existing policy-related tools that rely on simple calculation methods have limited ability to represent the dynamic interconnectedness of technology options and the impact of possible future changes in climate and occupant behaviour. The use of detailed simulation tools to address these limitations in the context of policy development has hitherto been focussed on the modelling of a number of representative designs rather than dealing with the spread inherent in large building stocks. Further, these tools have been research-oriented and largely unsuitable for direct use by policy-makers, practitioners and, ultimately, building owners/occupiers. This paper summarises recent initiatives that have applied advanced modelling and simulation in the context of policy formulation for large building stocks. To exemplify the stages of the process, aspects of the ESRU Domestic Energy Model (EDEM) are described. EDEM is a policy support tool built on detailed simulation models aligned with the outcomes of national surveys and future projections for the housing stock. On the basis of pragmatic inputs, the tool is able to determine energy use, carbon emissions and upgrade/running cost for any national building stock or subset. The tool has been used at the behest of the Scottish Building Standards Agency and South Ayrshire Council to determine the impact of housing upgrades, including the deployment of new and renewable energy systems, and to rate the energy/carbon performance of individual dwellings as required by the European Commission's Directive on the Energy Performance of Buildings (EC 2002).