| 1. |
- Lundqvist, Eva, 1985-
(author)
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Distal radius fractures AO type C : A clinical and radiographic investigation
- 2022
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Doctoral thesis (other academic/artistic)abstract
- The function of the hand is of substantial importance, and injuries have an impact on daily life. Distal radius fracture (DRF) is the most common fracture among adults. The annual incidence is 26 per 10,000 inhabitants, and the incidence is increasing because of an aging population. There has been a shift from conservative and other operative treatments, toward volar plate fixation to restore the anatomy and improve results. Operative treatment is often considered for displaced and unstable fractures. The optimal choice of treatment and fixation is still debated. The aim of this thesis was to study results after internal fixation of DRF AO type C.Study I (retrospective study, n=74) assessed outcomes after combined plating (CP) of DRFs AO type C, with 1-year follow-up. CP restored the anatomy and achieved a good functional outcome. The radiographic outcome did not correspond to the clinical or functional outcome.Study II (prospective study, n=97) assessed the prevalence of post-traumatic arthritis (PA) following CP of DRFs AO type C. CP yielded a good clinical outcome 7 years postoperatively and the prevalence of PA was low (29%). The presence of PA did not correlate with fracture group, radio-graphic, clinical, or functional outcome. Study III (randomized controlled trial, n=147) assessed the radiographic and clinical outcome following surgical treatment of DRFs AO type C, comparing volar plating (VP) with CP. Fixation with VP yieldedthe same radiographic and functional results as CP, but with a lower frequency of complications in the VP group.Study IV (prospective pilot study, n=10) assessed fragment migration with CTMA (CT-based micromotion analysis) after osteosynthesis with VP after DRF AO type C. The CTMA technique indicated that variable angle volar locking plate fixation can yield and maintain a stable reduction of the fracture fragments. CT volume registration could be a valuable tool in the detailed assessment of fracture fragment migration following VP fixation of DRFs.
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| 2. |
- Anund Vogel, Jonas, 1981-
(author)
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Incentivising Innovation in the Swedish Construction Industry
- 2020
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Doctoral thesis (other academic/artistic)abstract
- Almost 40 percent of global final energy use and CO2 emissions are connected to buildings and building-related activities; it is therefore important to incentivise the design and construction of resource-efficient buildings. Unfortunately, energy demand and associated emissions in the sector continue to grow. Such incentives will help achieve energy and environmental targets, reduce costs, and make smart and sustainable buildings and cities possible at a larger scale. Because novel technologies carry risks alongside their advantages, developers, contractors and consultants must have incentives to reduce and share those risks in a rational way if we are to meet the crucial long-term societal goals of reduced use of resources and emissions. I hypothesise that there are legal and institutional frameworks (rules, building codes, regulations, standard contracts, etc.) that result in weak or negative incentives for construction industry actors to invest in, propose, and install resource-efficient technologies. If the hypothesis holds true, then the goal is to identify ways to better incentivise construction industry actors to fully engage in the design and construction of smart and sustainable buildings. To tackle this, four studies were carried out using a mixed-method approach. Paper 1 identifies 38 barriers to energy efficiency in Swedish multifamily buildings. The next study (Paper 2) develops a categorisation framework in order to understand where to engage to overcome or bypass barriers to energy efficiency. Paper 3 and 4 are devoted to analysing two sets of barriers and propose possible solutions to overcome or avoid them: (1) how the current legal framework guiding start and operation of housing co-operatives (mainly the Co-operative Act) influences incentives for engaging in resource-efficient construction, and (2) how the legal instrument for collaboration between developers and consultants incentivises resource-efficient construction. In this case, the contract under investigation is the General Conditions of Contract for Consulting Agreements for Architectural and Engineering Assignments (ABK 09)”. Changes to these two sets of legal and institutional frameworks could have a significant impact on how buildings are designed, produced and used. The changes proposed could incentivise construction industry actors to fully pursue the creation of smart, sustainable buildings that deliver services to users and reduce negative environmental impacts stemming from both the building construction and operation phases.
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| 3. |
- Bäcklund, Katarina, 1982-
(author)
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Human-Centric Operations of Smarter Higher Educational Buildings in Sweden
- 2024
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Doctoral thesis (other academic/artistic)abstract
- This PhD thesis is based on four articles, each focused on distinct research areas: building occupants, smarter higher educational buildings, smart building systems and the digital transformation of real estate organizations. Rather than concentrating on one specific research area, the objective was to provide a comprehensive view of the broader system and delve into these four key research areas. Thus, they are all interdependent and require equal attention to facilitate the digital transformation within the commercial real estate industry. This transformation aims to create a more climate neutral built environment while ensuring good quality indoor comfort. The findings reveal a paradox within smart building systems, where building occupants are often treated as passive agents and interactions are intentionally reduced. However, it can be argued that some interactions will be beneficial, as building occupants considered as active agents could contribute to a more sustainable building operation. This study also concludes that current smart buildings are not yet smart enough and that all data is not smart data. Furthermore, the investigation into what constitutes a smart building has led to the identification of key features of smarter higher educational buildings. Finally, the concluding part of this study delved into the organizational challenges associated with digital transformation, proposing potential solutions to enhance innovation processes. Based on these findings, a framework for human-centric digital transformation was proposed.
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| 4. |
- Choque Campero, Luis Antonio, 1986-
(author)
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The Stirling engine as a part of a hybrid power system : a study of applications in rural areas of Bolivia
- 2021
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Licentiate thesis (other academic/artistic)abstract
- Rural electrification in developing countries has become one of the greatest challenges for achieving global access to electricity—one of the United Nation’s sustainable development goals. Governments, international entities and private companies are tasked with improving the quality of life for people and reducing environmentally harmful emissions. Bolivia’s political agenda has been working in coordination with international cooperation organizations, and it has achieved great improvements in access to electricity in recent years. Different strategies and technologies have been used in the various climate scenarios that span Bolivia’s territory. Although more Bolivians have access to electricity than 10 years ago, insufficient knowledge, training, and follow-up from local and national actors (such as power producers, power distributors, and electricity service providers) prevent these solutions from operating as expected.This study explores the integration of a Stirling engine into a small power production system for use in remote rural areas. The Stirling engine is a well-known technology that can use local fuels to generate power and heat. Here two different hybrid power systems in three case studies are compared: the first system is using photovoltaic (PV) panels, batteries, and diesel engines and the second is using PV panels, batteries, and Stirling engines. In a sustainability analysis the environmental effects, economy, and performances—efficiency and reliability—of the two systems are compared. In addition, the study discusses the maintenance of the Stirling engine in Bolivia rural conditions.The study began by gathering data from 17 households in different communities, which had just obtained access to electricity. These communities are characterized by different environmental and climate conditions, which allows us to better understand how the systems operate under Bolivia’s varying climate and to consider the state of its economy and technical capacity. With the help of GIS (Geographical Information System) maps, three Bolivian communities were selected: Tirina, Tablani, and El Carmen. Six hybrid power system were simulated for these communities, two dynamic models per community. The comparison between the two systems shows that Stirling engine hybrid power system produces at least 7 Tons per year less CO2 emissions than the Diesel hybrid power system per community. The financial analysis used the levelized cost of electricity (LCOE) to show the two systems’ cost per kilowatt-hour (in USD). The LCOE of the Stirling system is higher than the diesel engine in the three communities. The net present value was calculated to reflect the costs of the initial investment, as well as maintenance, spare parts, and so on, over the duration of the study. Finally, performance of the two systems was analyzed through a simulated one-day dynamic test of both systems in the three communities. The two systems responded without problem to the communities’ power demands. These power demands have peaks between about 5 kW and 7 kW.
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| 5. |
- Anund Vogel, Jonas, 1981-, et al.
(author)
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Co-Creation in Living Labs to Accelerate Innovation
- 2020
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In: Civil Engineering Research Journal. - Irvine California United States : Juniper Publishers. - 2575-8950. ; 10:1
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Journal article (other academic/artistic)abstract
- Innovation in the construction sector occurs as stepwise reconfigurations of subsystems, but sometimes the effect of many systems coincides and there is so called radical change. Stepwise reconfigurations of individual systems such as windows, insulation, and heat recovery systems have made it possible to heat buildings with preheated inlet air instead of water radiators. Thus, making building more sustainable, cheaper and resource-efficient; the potential for radical change has been achieved. The question is then why not every new building uses preheated inlet air? The reason is not the lack of innovation or new technologies. It is rather connected to malfunctioning structures related to incentives, collaboration, testing, and validation, resulting in norms and standards that aim to reproduce existing technologies, preferring incremental innovations over radical ones.This article argues that testbeds and Living Labs are a way to work on complex, multi-stakeholder and urgent problems in a co-creative way. In these labs there are possibilities to test technologies, in systems, in real buildings and cities. There are possibilities to follow-up, measure and adjust; to live, study, work and develop. The Living Labs have the potential of making new technologies standard to use in the course of years instead of decades and thus minimize unnecessary use of resources linked to the construction and use of buildings. In addition, it will help to make technologies more user-friendly, considering user needs, wishes and experiences, thus contributing to the effectiveness of the technologies developed and tested.
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| 6. |
- Bäcklund, Katarina, 1982-, et al.
(author)
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Building Occupants, Their Behavior and the Resulting Impact on Energy Use in Campus Buildings : A Literature Review with Focus on Smart Building Systems
- 2023
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In: Energies. - : MDPI AG. - 1996-1073. ; 16:17, s. 6104-6104
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Journal article (peer-reviewed)abstract
- In the light of global climate change and the current energy crisis, it is crucial to target sustainable energy use in all sectors. Buildings still remain one of the most energy-demanding sectors. Campus buildings and higher educational buildings are important to target due to their high and increasing energy demand. This building segment also represents a research gap, as mostly office or domestic buildings have been studied previously. In the quest for thermal comfort, a key stakeholder in building energy demand is the building occupant. It is therefore crucial to promote energy-aware behaviors. The building systems are another key factor to consider. As conventional building systems are replaced with smart building systems, the entire scenario is redrawn for how building occupants interact with the building and its systems. This study argues that behavior is evolving with the smartness of building systems. By means of a semi-systematic literature review, this study presents key findings from peer-reviewed research that deal with building occupant behavior, building systems and energy use in campus buildings. The literature review was an iterative process based on six predefined research questions. Two key results are presented: a graph of reported energy-saving potentials and a conceptual framework to evaluate building occupants impact on building energy use. Furthermore, based on the identified research gaps in the selected literature, areas for future research are proposed.
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| 7. |
- Bäcklund, Katarina, 1982-, et al.
(author)
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In Search for Untapped Energy-Saving Potential in Green and Smart Higher Educational Buildings—An Empirical Case Study Involving the Building Occupants
- 2023
-
In: Buildings. - : MDPI AG. - 2075-5309. ; 13:12
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Journal article (peer-reviewed)abstract
- Energy-intense activities and the unpredictable and complex behavior of building occupants lead to an increase in building energy demand. It is, therefore, crucial to study underlying factors for building energy demand related to the users. Higher educational buildings are relevant to study for several reasons: they host the future workforce and citizens, they are predicted to increase in numbers, and they represent a building type less studied. Furthermore, green-rated buildings equipped with smart building systems also represent a research gap that is relevant to address since such a building design involves IoT-functionalities and digital features for the building occupants to interact with. There is also a conceivable risk that if the users know that the building is green-rated and technologically advanced, this may alter their perception of the building operation and thus their behavior. To study the relationship between building occupants and such green and smart educational structure, a survey was conducted in a Swedish higher educational building; as a result, 300 responses were collected and analyzed. The responses revealed that the building occupants act with energy awareness, and they are conscious about energy-saving behaviors. One building feature in particular was studied: the Digital Room Panels (DRPs). The DRP allows the building occupants to modify the indoor temperature and is, therefore, essential for thermal comfort. One key finding from the survey revealed that 70% of the building occupants did not know how the DRPs operate. This study argues that this result can be explained with a lack of communication and user friendliness. Inadequate interactions with building systems could also result in opportunities for energy saving might not be realized. The findings of this case study led to valuable recommendations and suggestions for future research endeavors.
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| 8. |
- Bäcklund, Katarina, 1982-, et al.
(author)
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Showcasing a Digital Twin for Higher Educational Buildings : Developing the Concept Towards Human Centricity
- 2024
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In: Frontiers in Built Environment. - : Frontiers Media SA. - 2297-3362. ; 10
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Journal article (peer-reviewed)abstract
- Digital twin technology is an emerging technology within the built environment. There are yet many unexplored opportunities to utilize digital twins for facilitating the transformation towards a climate neutral building stock while also meeting the expectations from the building occupants. This article presents a case study of a digital twin, developed for an existing commercial building stock of campus areas in Sweden. The overarching purpose of the digital twin is to support both building occupants and building operators. This twofold human-centric approach represents a novel approach for building digital twins. The digital twin is based on 3D scanning and together with geospatial data, a real-like navigational indoor environment is created. Three innovative features are presented; the building analysis module, the digital twin mobile application and the building operations module. The results show that the digital twin improves the building occupant’s experience by supporting navigation and providing access to room booking system via this dedicated interface. Building management is also benefited by the digital twin through easier access to building data aggregated into one platform and a state-of-the-art analysis tool for optimizing the use of indoor space. The digital twin holds future potential to achieve operational excellence by incorporating feedback mechanisms and utilizing Artificial Intelligence to enable intelligent fault detection and prevention. Keywords:
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| 9. |
- Bäcklund, Katarina, 1982-, et al.
(author)
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Showcasing the First Steps Towards a Digital Twin for Campus Environments
- 2022
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In: 2022 BuildSim Nordic. - : EDP Sciences.
-
Conference paper (peer-reviewed)abstract
- This paper presents a path towards the implementation of a Digital Twin for campus environments. The main purpose of the Digital Twin is to accomplish an advanced analytical tool, which supports building owners, building operators and building users to reach an improved performance of the building. Digital Twins is new to the building and the real estate industry, hence research within this field is scarce. This paper contributes to the research by providing a methodology to implement a Digital Twin of an existing building stock of campus areas in Sweden. The main results obtained so far are presented. They indicate that the potential of a Digital Twin expands beyond the aspects of a navigational digital 3D model, including a state-of-the-art app that is developed from the Digital Twin platform.
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| 10. |
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Friluftsliv explored : An environmental and outdoor teaching approach for knowledge, emotions and quality of life
- 2021
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Editorial collection (other academic/artistic)abstract
- Friluftsliv explored doesn’t only include nature knowledge, techniques in the outdoors and outdoor pedagogics but also covers ecology, human ecology, geography, environmental and societal questions, history, health, biology, craft and lots of practical activities -both for urban and rural friluftsliv. In this translation to English of the revised fifth edition of the Swedish book there are many activities and the text is suitable for the modern day.Friluftsliv embraces the feeling around the campfire, paddling along winding rivers and walking towards the distant blue mountains. But, it is also to whittle a stick, to remember your waterproofs and to find your way home.Knowledge emerges when you combine imagination with facts and the glint in your eyes, using all our outdoor environments: forests, water, the coast, mountains and the nature close at hand.Emotion is to swim in crystal clear water far out in the archipelago and to see the clouds gliding across the sky. But also, to be able to present other sides of yourself, to be fascinated by your own body, the struggling ant and the sight of frost on trees.Quality of life is to experience friluftsliv – as it happens!
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| 11. |
- Malakhatka, Elena, et al.
(author)
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Actors’ Network Analysis and Bi-Directional Value Exchange Matrix Development for Living Labs: KTH Live-In-Lab Case Study
- 2022
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In: Smart Services Summit. - Cham : Springer. ; , s. 139-147
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Book chapter (peer-reviewed)abstract
- In the scientific literature and in practice, quite a lot of attention is paidto the actors’ network analysis in living labs. Still, there is a lack of studies onvalue exchange between different actors in living laboratories. This study selectedthe distributed structure of the actors’ network in living lab since most European residential laboratories function according to this model. In the course of this exploratory study, we conducted two workshops: the first with participants from several European residential laboratories to discuss and co-design a framework for analyzingthe exchange of value between different stakeholders, and the second workshop—case study, where the proposed framework was applied on the actors network of the existed living laboratory—KTH Live-in-Lab. As a result, we got a detailed pictureof the network of actors and value exchange within the value co-creation model forKTH Live-in-Lab (Smart Home Services project).
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| 12. |
- Malakhatka, Elena, et al.
(author)
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Co-Creating Service Concepts for the Built Environment Based on the End-User's Daily Activities Analysis : KTH Live-in-Lab Explorative Case Study
- 2021
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In: Sustainability. - : MDPI. - 2071-1050. ; 13:4
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Journal article (peer-reviewed)abstract
- The purpose of this study is to synthesize the widely used theories about co-creation from two main perspectives: co-creation as an innovation process and co-creation as a design process applied to the service concept design in the built environment context. The architecture, engineering, and construction (AEC) industry do not have much application of end-user-oriented service design in general, especially with intensive co-creation processes. To facilitate such a process, we are using a living lab environment as a laboratorial model of the real built environment, but with the opportunity to have access to the end-users and different types of stakeholders. Using the KTH Live-in-Lab explorative case study, we were able to discuss the concept of co-creation by distinguishing between co-creation as innovation and co-creation as a design process, facilitating the process of co-creation of service concepts for the proposed built environment including methods from both perspectives: innovation and design, and evaluating the process of service concepts co-creation for the built environment from the point of innovation, knowledge transfer, sustainability, and user experience.
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| 13. |
- Malakhatka, Elena, 1989-, et al.
(author)
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Identification of everyday food-related activities with potential for direct and indirect energy savings : KTH Live–in–Lab explorative case study
- 2022
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In: Energy Policy. - : Elsevier BV. - 0301-4215 .- 1873-6777. ; 163, s. 112792-112792
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Journal article (peer-reviewed)abstract
- This exploratory study analyses the daily activities of the end-user in terms of assessing the potential for conserving direct and indirect energy. In the course of the study, a socio-technological system approach was applied, which made it possible to combine the methods of analysis and interaction of the social group (students) and technical infrastructure (living laboratory). The method of creating personas was also applied to segregate a large group of the population within one segment. This approach allowed us to consider in more detail the different types of behavior in the same segment. As a result, we got more personalized strategies for changing a behavior tailored for each individual persona. In conclusion, a recommendation was given on which policies implications and to which organizations to address.
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| 14. |
- Malakhatka, Elena, et al.
(author)
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Monitoring and Predicting Occupant's Sleep Quality by Using Wearable Device OURA Ring and Smart Building Sensors Data (Living Laboratory Case Study)
- 2021
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In: Buildings. - : MDPI AG. - 2075-5309. ; 11:10
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Journal article (peer-reviewed)abstract
- Today's commercially-off-the-shelf (COST) wearable devices can unobtrusively capture several important parameters that may be used to measure the indoor comfort of building occupants, including ambient air temperature, relative humidity, skin temperature, perspiration rate, and heart rate. These data could be used not only for improving personal wellbeing, but for adjusting a better indoor environment condition. In this study, we have focused specifically on the sleeping phase. The main purpose of this work was to use the data from wearable devices and smart meters to improve the sleep quality of residents living at KTH Live-in-Lab. The wearable device we used was the OURA ring which specializes in sleep monitoring. In general, the data quality showed good potential for the modelling phase. For the modelling phase, we had to make some choices, such as the programming language and the AI algorithm, that was the best fit for our project. First, it aims to make personal physiological data related studies more transparent. Secondly, the tenants will have a better sleep quality in their everyday life if they have an accurate prediction of the sleeping scores and ability to adjust the built environment. Additionally, using knowledge about end users can help the building owners to design better building systems and services related to the end-user's wellbeing.
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| 15. |
- Molinari, Marco, et al.
(author)
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Using living labs to tackle innovation bottlenecks: the KTH Live-In Lab case study
- 2023
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In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 338, s. 120877-120877
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Journal article (peer-reviewed)abstract
- The adoption of innovation in the building sector is currently too slow for the ambitious sustainability goals thatour societies have agreed upon. Living labs are open innovation ecosystems in real-life environments usingiterative feedback processes throughout a lifecycle approach of an innovation to create sustainable impact. In thecontext of the built environment, such co-creative innovation and demonstration platforms are needed tofacilitate the adoption of innovative technologies and concepts for more energy-efficient and sustainablebuildings. However, their feasibility is not extensively proven. This paper illustrates the implementation anddemonstrates the feasibility of the Living Labs Triangle Framework for buildings living labs. This conceptualframework has been used to conceive the KTH Live-In Lab, a living lab for buildings. The goal of the Live-In Labwas to create a co-creative open platform for research and education bridging the gap between industry andacademia, featuring smart building demonstrators. The Living Lab Triangle Framework has been deployed tomeet the goals of the Live-in Lab, and the resulting concept is described. This paper then analyses the meth-odological and operational results introducing performance metrics to measure the economic sustainability, thepromotion of multidisciplinary research and development projects, dissemination and impact. The results arecompleted with a SWOT analysis identifying its current strengths and weaknesses. The results collected in thiswork fill a missing gap in the scientific literature on the performance of living labs and provide empirical evi-dence on the sustainability and impact of living labs.
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| 16. |
- Radestad, A. F., et al.
(author)
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Long-term incidence of endometrial cancer after endometrial resection and ablation: A population based Swedish gynecologic cancer group (SweGCG) study
- 2022
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In: Acta Obstetricia et Gynecologica Scandinavica. - : Wiley. - 0001-6349 .- 1600-0412. ; 101:8, s. 923-930
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Journal article (peer-reviewed)abstract
- Introduction Minimally invasive methods to reduce menorrhagia were introduced in the 1980s and 1990s. Transcervical endometrial resection (TCRE) and endometrial ablation (EA) are two of the most frequently used methods. As none of them can guarantee a complete removal of the endometrium, there are concerns that the remaining endometrium may develop to endometrial cancer (EC) later in life. The primary aim was to analyze the long-term incidence of EC after TCRE and EA in a nationwide population. The secondary aim was to assess the two treatment modalities separately. Material and Methods The Swedish National Patient Registry and National Quality Registry for Gynecological Surgery were used for identification of women who had TCRE or EA performed between 1997-2017. The cohort was followed from the first TCRE or EA until hysterectomy, diagnosis of EC, or death. Follow-up data were retrieved from the National Cancer Registry and the National Death Registry. Expected incidence for EC in Swedish women was calculated using Swedish data retrieved from the NORDCAN project after having taken into account differences of age and follow-up time. Cumulative incidence of EC after TCRE and EA, was calculated. A standardized incidence ratio was calculated based on the expected and observed incidence, stratified by age and year of diagnosis. Results In total, 17 296 women (mean age 45.1 years) underwent TCRE (n = 8626) or EA (n = 8670). Excluded were 3121 who had a hysterectomy for benign causes during follow up. During a median follow-up time of 7.1 years (interquartile range 3.1-13.3 years) the numbers of EC were 25 (0.3%) after TCRE and 2 (0.02%) after EA, respectively. The observed incidence was significantly lower than expected (population-based estimate) after EA but not after TCRE, giving a standardized incidence ratio of 0.13 (95% confidence interval [CI] 0.03-0.53) after EA and 1.27 (95% CI 0.86-1.88) after TCRE. Median times to EC were 3.0 and 8.3 years after TCRE and EA, respectively. Conclusions There was a significant reduction of EC after EA, suggesting a protective effect, whereas endometrial resection showed an incidence within the expected rate.
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| 17. |
- Shahrooz, Mina, et al.
(author)
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Effect of waste heat utilization on the performance of low temperature rankine cycle
- 2020
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In: Refrigeration Science and Technology. - : International Institute of Refrigeration. ; , s. 455-462
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Conference paper (peer-reviewed)abstract
- Low temperature Rankine cycle is a prominent solution for power generation in Waste Heat Recovery (WHR) application. The performance of this cycle is affected by various parameters including characteristics of the heat source, working fluid and constraints in the system. In cases where the heat source has a limited mass flux and therefore variable temperature, the amount of extracted heat affects the performance of the cycle including net power and efficiency which is also related to the working fluid. This is in the paper expressed in terms of a heat utilization factor, ?, which shows the ratio of extracted heat to the maximum possible extraction rate in the specific case. This factor affects the performance of the cycle by moving the pinch point location in the evaporator. Results indicate that this factor has great impact on the performance of the cycle and the effect varies for different working fluids.
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| 18. |
- Shahrooz, Mina, et al.
(author)
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Performance of binary zeotropic mixtures in organic Rankine cycles (ORCs)
- 2022
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In: Energy Conversion and Management. - : Elsevier BV. - 0196-8904 .- 1879-2227. ; 266, s. 115783-
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Journal article (peer-reviewed)abstract
- Compared to pure fluids, zeotropic mixtures have the potential to lower the irreversibilities in low temperature Rankine cycles by better temperature profile matching of the working fluid with the heat source/sink. However, having a gliding temperature does not guarantee performance boost over pure fluids, as many factors influence the exergy efficiency of the cycle. In this study, 25 pure fluids and 104 binary mixtures of natural working fluids are analyzed in subcritical ORCs with heat source temperature range of 125-300 degrees C and different condensing conditions and the results are investigated within two frameworks: (1) comparing the mixtures to their pure constituents, (2) comparing the mixtures to the best performing pure fluid. In one behavior type, the performance of the mixture falls between the performance of its pure constituents for all evaporator pressure range, and the mixture provides no benefit. However, some mixtures could provide performance boost in a specific evaporator range. Therefore, the maximum allowable evaporator pressure plays an important role in the performance comparison of zeotropic mixtures to their pure constituents. Mixtures which outperform their pure constituents in the first perspective, are further analyzed in the second perspective. Finally, a screening method is presented to map the binary mixtures with performance boost compared to their pure constituents and high absolute exergy efficiency. This method is based on the key thermophysical properties of the fluids including critical temperature and normal boiling point, as well as working conditions such as heat source and heat sink temperature and PPTD in the evaporator and the condenser.
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