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News Article | April 23, 2017
Site: news.yahoo.com

Have you ever noticed why tomato juice is such a popular drink on planes? There is a scientific reason behind it and it's all to do with the impact of cabin pressure on our senses. It’s about 30 percent more difficult to detect sweet and salty tastes, according to a 2010 study by the Fraunhofer Institute for Building Physics in Germany. In other words, at altitude, our sense of taste is dulled. Business Insider spoke with Professor Charles Spence, Head of Crossmodal Research Laboratory at Oxford University and author of “Gastrophysics, The New Science of Eating,” about the subject. He said: "You see them shooting off the trolley here there any everywhere and when you do these surveys you find that there are about a quarter of people who will order a tomato juice or Bloody Mary in the air and would never order it on the ground. "If you give people tomato juice on the ground and on the air and say “well how does it taste different to you?” On the ground, it will tend to taste more earthy. Whereas up in the air people will often report that it taste a bit fresher a bit more acidic and is more liked as a result."

Torio H.,Fraunhofer Institute for Building Physics | Schmidt D.,Fraunhofer Institute for Building Physics
Renewable Energy | Year: 2010

Exergy analysis is a more powerful tool than mere energy analysis for showing the improvement potential of energy systems. Direct use of solar radiation instead of degrading other high quality energy resources found in nature is advantageous. Yet, due to physical inconsistencies present in the exergy analysis framework for assessing direct-solar systems commonly found in literature, high exergy losses arise in the conversion process of solar radiation in direct-solar systems. However, these losses are disregarded in indirect-solar systems.In this paper, contradictions and physical inconsistencies which result from including the conversion of solar radiation only for direct-solar systems are shown. An evaluation framework physically coherent for systems making direct and indirect use of solar radiation is derived and its physical correctness is thoroughly discussed. Results from case studies using the proposed framework are presented and compared with the conventional approach, enabling their direct comparison and better understanding of the benefits and correctness of the proposed method. The new method allows recognizing clearly the suitability of direct-solar systems, being appropriate for highlighting more sustainable energy supply systems.Although this paper focuses on building systems, the framework might be used for exergy analysis of direct-solar systems in the context of other energy uses. © 2010 Elsevier Ltd.

Lohani S.P.,University of Oldenburg | Schmidt D.,Fraunhofer Institute for Building Physics
Renewable Energy | Year: 2010

The energy and exergy flow for a space heating systems of a typical residential building of natural ventilation system with different heat generation plants have been modeled and compared. The aim of this comparison is to demonstrate which system leads to an efficient conversion and supply of energy/exergy within a building system. The analysis of a fossil plant heating system has been done with a typical building simulation software IDA-ICE. A zone model of a building with natural ventilation is considered and heat is being supplied by condensing boiler. The same zone model is applied for other cases of building heating systems where power generation plants are considered as ground and air source heat pumps at different operating conditions. Since there is no inbuilt simulation model for heat pumps in IDA-ICE, different COP curves of the earlier studies of heat pumps are taken into account for the evaluation of the heat pump input and output energy. The outcome of the energy and exergy flow analysis revealed that the ground source heat pump heating system is better than air source heat pump or conventional heating system. The realistic and efficient system in this study "ground source heat pump with condenser inlet temperature 30 °C and varying evaporator inlet temperature" has roughly 25% less demand of absolute primary energy and exergy whereas about 50% high overall primary coefficient of performance and overall primary exergy efficiency than base case (conventional system). The consequence of low absolute energy and exergy demands and high efficiencies lead to a sustainable building heating system. © 2009 Elsevier Ltd. All rights reserved.

Reiss J.,Fraunhofer Institute for Building Physics
Energy Procedia | Year: 2014

The amount of delivered energy used by educational buildings is equal to approx. 20 million MWh/a, about two thirds of which are used by school buildings. In the next few years, many school buildings will have to undergo major retrofits. Now this is the time to set the course for the future energy consumption of these buildings. In the scope of a demonstration project funded by the Federal Ministry of Economics and Technology it will be shown by which innovative measures the energy consumption of school buildings can be reduced by almost 80 % on average. These measures include energy retrofitting of the building envelope, of technical building services, and the use of renewable energy. After retrofitting, some school buildings now achieve plus energy standard, the other ones achieve the 3-litre building standard. Findings of this project will be contributed to SHC Task 47 (Solar Renovation of Non-Residential Buildings).

Ellerbrok C.,Fraunhofer Institute for Building Physics
Energy Procedia | Year: 2014

Within this work, load-shifting possibilities of heat pumps in residential buildings as well as its influencing and limiting factors are displayed. The intermediate storage is achieved by using the thermal mass of the building so the heat supply can be postponed from the heat demand for a certain period, depending on the characteristics of the building. No additional water storage is considered. © 2014 The Authors.

Kunzel H.,Fraunhofer Institute for Building Physics
Energy Procedia | Year: 2015

In the 1960s and 70s extensive experimental investigations were carried out at the open air test site of the Fraunhofer-Institute of Building Physics concerning the driving rain protection of Autoclaved Aerated Concrete (AAC) walls coated with innovative synthetic resin renders. Since some of the exposed test walls did not perform as well as others, a correlation between the water absorption and the vapour diffusion properties of the façade coatings was established. This correlation was subsequently introduced into the German Standard for exterior rendering systems with a slight modification to account for the special characteristics of mineral renders. When models to simulate transient heat and moisture transport processes in the building envelope were successfully applied in the middle of the 90s, parametric studies confirmed that the empirical correlation, established 30 years ago, is appropriate to define the rain protection characteristics of façade systems. However, the magnitude of the parameters depends on the climate conditions and the wall assembly. While the existing specifications are suitable for moderately insulating masonry, walls made out of well-insulated blocks may get too wet. Similarly, masonry structures with interior insulation may accumulate too much moisture behind the insulation layer unless the existing limit for the water absorption coefficient is reduced by 60% for high wind driven rain zones. Recent calculation results show that the local driving rain load and intermittent drying conditions as well as the characteristics of the substrate are the principle factors for selecting limit criteria for rain protecting rendering systems. © 2015 The Authors.

Schmidt D.,Fraunhofer Institute for Building Physics
International Journal of Exergy | Year: 2012

An optimisation of the exergy fl ows in buildings and the supply structures related to them, similar to other thermodynamic systems, can help in identifying the potential of increased effi ciency in energy utilisation. The low exergy (LowEx) approach entails matching the quality levels of exergy supply and demand to streamline the utilisation of high-value energy resources. This approach is the key concept for the conducted work. Using a typical case, the advantages of the analyses and the difference between energy and exergy analyses are demonstrated. In conclusion, suggestions, based on an analysis of a real and existing building, are presented for a benchmarking system for so-called LowEx buildings. Copyright © 2012 Inderscience Enterprises Ltd.

Ilg R.,Fraunhofer Institute for Building Physics
Green Design, Materials and Manufacturing Processes - Proceedings of the 2nd International Conference on Sustainable Intelligent Manufacturing, SIM 2013 | Year: 2013

With the growing environmental awareness in society, the demand for sustainable products and services increases. Hence especially in the expanding aviation sector, a reduction of the ecological impacts is intended to improve the aviation's ecological footprint. Modelling a whole life cycle inventory in a LCA study compliant with the ISO 14040 requires comprehensive expert knowledge. Furthermore aircrafts are complex systems with millions of different parts and various, aviation specific materials. To enable non-experts with little or no LCA knowledge like aircraft designers to assess the environmental impacts of already existing and also of conceptual aircrafts by the method of LCA, the web-based Tool EcoSky was developed with an easy-to-use user interface. In this Tool, the complex LCI modelling is decoupled from the design process. The presentation highlights the characteristics of the aerospace sector and how the EcoSky Tool deals with the specific difficulties. © 2013 Taylor & Francis Group.

Torio H.,Fraunhofer Institute for Building Physics | Schmidt D.,Fraunhofer Institute for Building Physics
Energy and Buildings | Year: 2010

The building sector is responsible for a great share of the final energy demand and national CO2 emissions in countries like Germany. Nowadays, low quality thermal energy demands in buildings are mainly satisfied with high-quality sources (e.g. natural gas fired in condensing boilers). Exergy analysis, pursuing a matching in the quality level of energy supplied and demanded, pinpoints the great necessity of substituting high-quality fossil fuels by other low quality energy flows, such as waste heat. In this paper a small district heating system in Kassel (Germany) is taken as a case study. Results from preliminary steady-state and dynamic energy and exergy analysis of the system are presented and strategies for improving the performance of waste-heat based district heating systems are derived. Results show that lowering supply temperatures from 95 to 57.7 °C increases the final exergy efficiency of the systems from 32% to 39.3%. Similarly, reducing return temperatures to the district heating network from 40.8 to 37.7 °C increases the exergy performance in 3.7%. In turn, the energy performance of all systems studied is nearly the same. This paper shows clearly the added value of exergy analysis for characterising and improving the performance of district heating systems. © 2010 Elsevier B.V. All rights reserved.

Luck K.,Fraunhofer Institute for Building Physics
Journal of Cleaner Production | Year: 2012

The main focus of this paper is a literature review of analyses of high performance indoor environments which aid in the design of appropriate energy efficient Heating-Ventilation Air Conditioning (HVAC) systems. In the past, investors planned and built interiors primarily according to economic considerations. Aspects of performance-oriented interior spaces were not taken into account. Yet, to meet growing expectations and requirements, it is necessary to combine thermal comfort features and energy efficient HVAC systems. A huge amount of electricity is necessary for the operation of these systems. Overall, one-third of the final energy is consumed by the provision of space heating and hot water in Germany. More than 95% of this demand is met through the use of fossil fuel. There is, however, a great potential to reduce CO 2 emissions. Forward-thinking planning includes both the careful use of resources and the optimization of performance promoting rooms. The main emphasis in this case is on the well-being of humans, promoting their performance and hence their efficiency, and on achieving high exergetic efficiency. © 2011 Elsevier Ltd. All rights reserved.

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