A previously developed turbine modelling methodology, requiring minimal blade passage information, produced a customizable turbine stage component. This stage-by-stage turbine nozzlemodel component was derived from the synthesis of classical turbine theory and classical nozzle theory enabling the component to accurately model a turbine stage. Utilizing Flownex, a thermohydraulic network solver, the turbine stage component can be expanded to accurately model any arrangement and category of turbine. This project focused on incorporating turbine blade passage geometrical information, as it relates to the turbine specific loss coefficients, into the turbine stage component to allow for the development of turbine models capable of predicting turbine performance for various structural changes, anomalies and operating conditions. The development of turbine loss coefficient algorithms as they relate to specific blade geometry data clusters required the investigation of several turbine loss calculation methodologies. A stage-by-stage turbine nozzle-model incorporating turbine loss coefficient algorithms was developed and validated against real turbine test cases obtained from literature. Several turbine models were developed using the loss coefficient governed turbine stage component illustrating its array of capabilities. The incorporation of the turbine loss coefficient algorithms clearly illustrates the correlation between turbine performance deviations and changes in specific blade geometry data clusters.

In the year 2006, the energy performance directive 2002/91/EG was passed by the European Union, according to this directive the Swedish building code was supplemented by a key measure of energy use intensity (EUI). The implemented EUI equals some energy use within a building divided by its floor area and must be calculated in new housing estate and shown when renting or selling housing property. In order to improve the EUI, energy efficiency refurbishments could be implemented. Building energy simulation tools enables a virtual view a building model and can estimate the energy use before implementing any refurbishments. They are a powerful resource when determine the impact of the refurbishment measure. In order to obtain a correct model which corresponds to the actual energy use, some adjustments of the model are often needed. This process refers to as calibration. The used EUI has been criticized and thus, the first objective in this work was to suggest an alternative key measure of a buildings performance. The results showed that the currently used EUI is disfavoring some districts in Sweden. New housing estate in the far north must take more refined actions in order to fulfill the regulation demand, given that the users are behaving identical regardless where the house is located. Further, the suggested measure is less sensitive to the users’ behavior than the presently used EUI. It also has a significance meaning in building design as it relating the building shape and thermal properties and stating that extreme building shapes must undergo a stricter thermal construction rather than buildings that are more compact. Thus, the suggested key measure also creates a communication link between architects and the consultant constructors. The second objective of this thesis has been to investigate a concept of calibration using the data normally provided by energy bills, i.e. some monthly aggregated data. A case study serves to answer this objective, by using the building energy simulation tool IDA ICE 4.7 and a building located in Umeå, Sweden. The findings showed that the used calibration approach yielded a model considered as calibrated in eleven of twelve months. Furthermore, the method gives a closer agreement to the actual heat demand rather than using templates and standardized values. The major explanation of the deviation was influence of the users, but also that the case study building burden with large heat losses by domestic hot water circulation and thus, more buildings should be subjected to this calibration approach.

Adapting pipes are a significant part of any pipe-line network and they are the sources of substantial hydraulic losses. They are designed for a manufacturing simplicity, regardless of flow. This paper concerns with lowering of hydraulic losses of adapting pipes by means of the shape optimization. Several methods of a mathematical optimization are tested and due to the complexity of the task and the need of the computational distribution among several computers, the gradient based algorithm is used. These methods loop together with a CFD software then automatically explore the design space. Several optimizations of diffusers with different opening angles, shape parameterizations and boundary conditions are made for the better insight on hydraulic losses. In three chapters there is description of development of parametric description of bend by means of Bezier surfaces. At the end optimum shape is found with hydraulic losses were decreased about 22%, which was not validated by experiment. In the final chapter is application of developed software on the shape optimization of Kaplan draft tube.

Many existing dams in the United States were built without hydroelectric generating accessories and are now being considered for hydroelectric installations. A bifurcation is regularly used as the method for diverting the water to the new generators. With a bifurcation installed as part of the new piping system, cavitation could become a problem. Although widely used, there are no published data on cavitation characteristics or head loss coefficients for these bifurcations. Dimensional analysis has not been adequate for experimentally quantifying the cavitation potential and full scale testing is prohibitive for many large geometries. Therefore this study utilized Computational Fluid Dynamics (CFD) in conjunction with a physical model to predict conditions that would cause the onset of cavitation. Head loss coefficients were also calculated from the CFD simulations and physical model. Based on these results, the authors have produced recommended operating conditions that will allow bifurcations to operate within safe limits of cavitation. This study was not exhaustive but presents data that has previously been unavailable and will assist designers and operators to better understand the performance of such bifurcations.

Adapting pipes are a significant part of any pipe-line network and they are the sources of substantial hydraulic losses. They are designed for a manufacturing simplicity, regardless of flow. This paper concerns with lowering of hydraulic losses of adapting pipes by means of the shape optimization. Several methods of a mathematical optimization are tested and due to the complexity of the task and the need of the computational distribution among several computers, the gradient based algorithm is used. These methods loop together with a CFD software then automatically explore the design space. Several optimizations of diffusers with different opening angles, shape parameterizations and boundary conditions are made for the better insight on hydraulic losses. In three chapters there is description of development of parametric description of bend by means of Bezier surfaces. At the end optimum shape is found with hydraulic losses were decreased about 22%, which was not validated by experiment. In the final chapter is application of developed software on the shape optimization of Kaplan draft tube.

When designing a pipeline system, it is important to understand the pressure losses that will occur within the system. One common source of pressure loss is from elbow pipe fittings. There is extensive research available for pressure loss coefficients of elbow pipe fittings, but the research is derived from elbows with relatively smaller pipe diameters. The purpose of this research is to investigate pressure losses associated with larger diameter mitered elbows (36-inches to 144-inches). The dimensions for all mitered elbows considered in this research follow ANSI/AWWA C208-17 recommendations (AWWA 2017). Due to the large size of the mitered elbows of interest, physical testing was not feasible for this research. Therefore, this research used numerical methods to determine the pressure loss coefficients of large mitered elbows, reducing mitered elbows, and expanding mitered elbows. The results suggest a strong correlation that the pressure loss for large mitered elbows, presented in this research, are solely dependent on the pipe Reynolds number. The reducing and expanding mitered elbows showed the pressure loss coefficient is dependent on Reynolds number and the percent of reduction/expansion of the elbow. Tabulated data, graphical data, and recommended equations are presented to determine pressure loss for large mitered elbows, reducing mitered elbows, and expanding elbows.

<p>Today many professional property holders use different types of software for monthly energy analyses. The data is however often limited to energy and water use, that is paid for by the property holder. In year 2001, financed by the Swedish Energy Agency, the first steps were taken to create a national web based data base, eNyckeln. A property holder may then enter consumption data together with about 50 other building specific parameters to this data base in order to enable benchmarking and energy performance evaluations. Due to EU-regulations and the increasing awareness of energy and environmental issues there is a large interest in evaluating the energy performance and also to identify effective energy retrofits. The used energy performance indicator is still only the annual energy use for heating per square meter of area to let, kWh/m²,year, despite the fact that monthly data often are available. The main problem with this indicator, which is the stipulated measure, is that it reflects a lot of user influence and that only a part of the total energy use is considered. The main focus of this thesis is to explore the possibilities, based on the national data base, to extract additional energy information about multi family buildings (MFB) using monthly data in combination with different assumed consumption pattern but also to identify potential for energy savings. For the latter a multivariate method was used to identify relations between the energy use and building specific parameters. The analysis gave clear indications that the available area, the area to let, is not appropriate for normalization purposes since the remaining heated area can be significant. Due to this fact, the analysis was mainly limited to qualitative conclusions. As measure of the buildings energy characteristic, the total heat loss coefficient, <em>K_tot</em>,(W/ºK) is determined and the robustness for the estimate of<em> K_tot</em> to different assumptions of user behaviour is investigated. The result shows that the value of <em>K_tot</em> is fairly insensitive to different indoor temperature, use of domestic hot water and household electricity. With the addition of m² it can of course be used for benchmarking. Using the mentioned measure of the buildings energy characteristic for validating the energy performance has a clear advantage compared to the traditional kWh/m², since the user behaviour is of minor importance. As a result of this an improved analysis of the energy performance will be obtained. A guarantee for new buildings energy performance based on this method is therefore a challenge for the building sector to develop.</p>

The  aim  of  this  master  thesis  is  an  investigation  of  the  thermal  performance  of  a  thermal compound parabolic concentrating (CPC) collector from Solarus. The collector consists of two troughs with absorbers which are coated with different types of paint with  unknown  properties.  The  lower  and  upper  trough  of  the  collector  have  been  tested individually. In  order  to  accomplish  the  performance  of  the  two  collectors,  a  thorough  literature  study  in  the  fields  of  CPC  technology,  various  test  methods,  test  standards  for  solar thermal  collectors  as  well  as  the  latest  articles  relating  on  the  subject  were  carried  out. In addition, the set‐up of the thermal test rig was part of the thesis as well. The thermal  performance  was  tested  according  to  the  steady  state  test  method  as  described in the European standard 12975‐2. Furthermore, the thermal performance of  a  conventional  flat  plate  collector  was  carried  out  for  verification  of  the  test  method. The  CPC‐Thermal  collector  from  Solarus  was  tested  in  2013  and  the  results  showed  four  times  higher  values  of  the  heat  loss  coefficient  UL (8.4  W/m²K)  than  what  has been reported for a commercial collector from Solarus. This value was assumed to be too large and it was assumed that the large value was a result of the test method used that time. Therefore, another aim was the comparison of the results achieved in this work with the results from the tests performed in 2013. The results of the thermal performance showed that the optical efficiency of the lower trough of the CPC‐T collector is 77±5% and the corresponding heat loss coefficient UL 4.84±0.20  W/m²K.  The  upper  trough  achieved  an  optical  efficiency  of  75±6  %  and  a  heat loss coefficient UL of 6.45±0.27 W/m²K. The results of the heat loss coefficients  are  valid  for  temperature  intervals  between  20°C  and  80°C.  The  different  absorber paintings have a significant impact on the results, the lower trough performs overall better.  The  results  achieved  in  this  thesis  show  lower  heat  loss  coefficients UL and higher optical efficiencies compared to the results from 2013.

Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2011. / Despite the extensive research work carried out on flow through short square-edged orifice plates over the last century (e.g. Johansen, 1930; Benedict, 1977; Alvi et al., 1978; Swamee, 2005; ESDU, 2007), gaps in the engineering data still exist for certain ranges of flow conditions and geometries. The majority of data available in the literature are for Newtonian fluids in the turbulent flow regime (ESDU, 2007). Insufficient data have been observed for the orifice with pipe diameter ratio, β = 0.2, in the laminar flow regime. There are no experimental data for β = 0.3 and 0.57. The objective of this thesis was to conduct wide-ranging experimental studies of the flow in orifice plates, which included those geometrical configurations, by measuring pressure loss coefficients and discharge coefficients across the orifice plates using both Newtonian fluids and non-Newtonian fluids in both laminar and turbulent flow regimes. The test work was conducted on the valve test rig at the Cape Peninsula University of Technology. Four classical circular short square-edged orifice plates having, β = 0.2, 0.3, 0.57 and 0.7, were tested. In addition, two generation 0 Von Koch orifice plates (Von Koch, 1904), with equivalent cross sectional area were also tested for β = 0.57. Water was used as Newtonian fluid to obtain turbulent regime data and also for calibration purposes to ensure measurement accuracy and carboxymethyl cellulose, bentonite and kaolin slurries were used at different concentrations to obtain laminar and transitional loss coefficient data. The hydraulic grade line method was used to evaluate pressure loss coefficients (Edwards et al., 1985), while the flange tap arrangement method was used to determine the discharge coefficients (ESDU, 2007). A tube viscometer with three different pipe diameters was used to obtain the rheological properties of the fluids. The results for each test are presented in the form of pressure loss coefficient (kor) and discharge coefficient (Cd) against pipe Reynolds number (Re)

Today many professional property holders use different types of software for monthly energy analyses. The data is however often limited to energy and water use, that is paid for by the property holder. In year 2001, financed by the Swedish Energy Agency, the first steps were taken to create a national web based data base, eNyckeln. A property holder may then enter consumption data together with about 50 other building specific parameters to this data base in order to enable benchmarking and energy performance evaluations. Due to EU-regulations and the increasing awareness of energy and environmental issues there is a large interest in evaluating the energy performance and also to identify effective energy retrofits. The used energy performance indicator is still only the annual energy use for heating per square meter of area to let, kWh/m2,year, despite the fact that monthly data often are available. The main problem with this indicator, which is the stipulated measure, is that it reflects a lot of user influence and that only a part of the total energy use is considered. The main focus of this thesis is to explore the possibilities, based on the national data base, to extract additional energy information about multi family buildings (MFB) using monthly data in combination with different assumed consumption pattern but also to identify potential for energy savings. For the latter a multivariate method was used to identify relations between the energy use and building specific parameters. The analysis gave clear indications that the available area, the area to let, is not appropriate for normalization purposes since the remaining heated area can be significant. Due to this fact, the analysis was mainly limited to qualitative conclusions. As measure of the buildings energy characteristic, the total heat loss coefficient, Ktot,(W/ºK) is determined and the robustness for the estimate of Ktot to different assumptions of user behaviour is investigated. The result shows that the value of Ktot is fairly insensitive to different indoor temperature, use of domestic hot water and household electricity. With the addition of m2 it can of course be used for benchmarking. Using the mentioned measure of the buildings energy characteristic for validating the energy performance has a clear advantage compared to the traditional kWh/m2, since the user behaviour is of minor importance. As a result of this an improved analysis of the energy performance will be obtained. A guarantee for new buildings energy performance based on this method is therefore a challenge for the building sector to develop.