| 1. |
- Bengtsson, Cecilia, 1974, et al.
(författare)
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Co-ordination of pinch technology and the MIND method : applied to a Swedish board mill
- 2002
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Ingår i: Applied Thermal Engineering. - 1359-4311 .- 1873-5606. ; 22:2, s. 133-144
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Tidskriftsartikel (refereegranskat)abstract
- By combining the pinch technology and the MIND method, it is possible to identify beneficial and energy-efficient measures in a complex industrial energy system. By tackling a problem on the two different aggregation levels, the result is thoroughly evaluated and durable measures are achieved. The strength of the combination of methods is elucidated in a case study where a Scandinavian pulp and paper mill is analysed. The studied problem concerns pre-evaporation of effluents in a board mill using excess heat. Different alternatives are evaluated, taking into account economic, technical and practicable constraints. The results show that it is cost-effective to pre-evaporate the effluent using excess heat in the studied mill.
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| 2. |
- Gebremedhin, Alemayehu, 1962-
(författare)
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The role of a paper mill in a merged district heating system
- 2003
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Ingår i: Applied Thermal Engineering. - 1359-4311 .- 1873-5606. ; 23:6, s. 769-778
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies have shown that there is great potential benefit in utilities collaborating around heat supply. Analyses based on an extended system boundary clarify the advantage of mutual co-operation in the district heating markets. The purpose of this study is to show how far a local paper mill affects the degree of co-operation between two utilities. Current and future electricity prices and existing and potential plants are considered in the different scenarios in the study. The results in all the scenarios clearly show that the paper mill plays an active role in an integrated heat supply system. The scenario where co-operation, new plants and future electricity prices are considered, gives the lowest total system cost. A new back pressure turbine with a higher electricity-to-heat output ratio in combination with high trade prices promotes increased electricity and heat generation in the co-generation plant. The proportion of combined heat and power in district heating would increase if co-operation between the players were encouraged. ⌐ 2003 Elsevier Science Ltd. All rights reserved.
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| 3. |
- Gustafsson, Stig-Inge
(författare)
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Optimization and simulation of building energy systems
- 2000
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Ingår i: Applied Thermal Engineering. - 1359-4311 .- 1873-5606. ; 20:18, s. 1731-1741
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Tidskriftsartikel (refereegranskat)abstract
- The Mixed Integer Linear Programming (MILP) technique is a useful tool for the optimization of energy systems. However, the introduction of integers in linear models results in a severe drawback because the ranging process is no longer available. Therefore, it is not possible to study what happens to the solution if input data are changed. In this paper, we compare a MILP model of a building with a simulation model of an identical case. Both models describe a building with a number of possible retrofits. Using the MILP technique, the optimal retrofit strategy is calculated, after which certain input data are changed. The optimization results in the lowest possible Life-Cycle Cost (LCC) of the building, and the paper describes how much the LCC will change if the property owner chooses other solutions. An increase in a particular data value may cause the LCC to increase or decrease. It may also be unchanged. Only a few data reduce the LCC when their values are increased.
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| 4. |
- Heidari, Tari Mehrdad, et al.
(författare)
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Modelling of thermal energy storage in industrial energy systems the method development of MIND
- 2002
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Ingår i: Applied Thermal Engineering. - 1359-4311 .- 1873-5606. ; 22:11, s. 1195-1205
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Tidskriftsartikel (refereegranskat)abstract
- Industrial energy efficiency is of vital importance as regards environment and industrial profitability. Optimisation of industrial energy systems may show a way towards improved use of resources in energy supply as well as in production processes. The deregulation of the electricity market in some countries increases flexibility in electricity contracts. Taking advantage of the price structure in these contracts is one of the ways to minimise the energy costs and decrease the influence on the environment. Thermal energy stores are very suitable facilities for achieving these goals, having the capability of moving energy use from one period of time to another and thereby influencing not only energy cost but also costs related to power demand if electric energy use is involved. In this paper, the influence on energy costs, energy and material flows resulting from the use of energy storage is discussed. Energy storage has been modelled by using MIND (Method for analysis of INDustrial energy systems) in the form that has recently been developed by the author. A case study from the pulp and paper industry has been used to verify this. © 2002 Elsevier Science Ltd. All rights reserved.
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| 5. |
- Ji, Xiaoyan, et al.
(författare)
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Survey of experimental data and assessment of calculation methods of properties for the air–water mixture
- 2003
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Ingår i: Applied Thermal Engineering. - 1359-4311 .- 1873-5606. ; 23:17, s. 2213-2228
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Tidskriftsartikel (refereegranskat)abstract
- Thermodynamic properties of the air-water mixture at elevated temperatures and pressures are of importance in the design and simulation of the advanced gas turbine systems with water addition. In this paper, comprehensive available experimental data and calculation methods for the air-water mixture were reviewed. It is found that the available experimental data are limited, and the determined temperature is within 75 °C. New experimental data are needed to supply in order to verify the model further. Three kinds of models (ideal model, ideal mixing model and real model) were used to calculate saturated vapor composition and enthalpy for the air-water mixture, and the calculated results of these models were compared with experimental data and each other. The comparison shows that for the calculation of saturated vapor composition, the reliable range of the ideal model and ideal mixing model is up to 10 bar. The real model is reliable over a wide temperature and pressure range, and the model proposed by Hyland and Wexler is the best one of today. However, the reliability of the Hyland and Wexler model approved by experimental data is only up to 75 °C and 50 bar, and it is necessary to propose a new predictive model based on the available experimental data to be used up to elevated temperatures and pressures. In the calculation of enthalpy, compared to the ideal model, the calculated results of the ideal mixing model are closer to those of real model.
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| 6. |
- Amos, I. G., et al.
(författare)
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Design and off-design optimisation of highly loaded industrial gas turbine stages
- 2004
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Ingår i: Applied Thermal Engineering. - : Elsevier BV. - 1359-4311 .- 1873-5606. ; 24:12-nov, s. 1735-1744
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Tidskriftsartikel (refereegranskat)abstract
- A European collaborative project to investigate the design of advanced industrial gas turbine stages (DAIGTS) has now completed 30 months of a 36-month programme of work. The objectives of the project were to investigate advanced aerodynamic analysis of industrial gas turbine stages, off-design performance characteristics, prediction of aero-mechanical behaviour.This paper gives an overview of the technical progress made and includes a description of the rigs used in the study. Key results include the development of advanced CFD models to include cooling and real engine geometric features, off-design performance mapping of transonic industrial turbine stages and the development of a unique oscillating cascade rig.
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| 7. |
- Bacos, M P, et al.
(författare)
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ALLBATROS advanced long life blade turbine coating systems
- 2004
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Ingår i: Applied Thermal Engineering. - : Elsevier BV. - 1359-4311 .- 1873-5606. ; 24:11-12, s. 1745-1753
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Tidskriftsartikel (refereegranskat)abstract
- The scientific and technological objectives of this program are to increase the efficiency, reliability and maintainability of industrial gas turbine blades and vanes by• developing coatings that can warrant a 50 000 h life, i.e. twice that of the usual life, of the hot components (800–1100 °C) even with the use of renewable fuels such as biomass gas or recovery incinerator gas i.e. low-grade fuels with high pollutant levels,• characterising advanced existing coatings to assess lifetime and performance of coatings and coated materials,• providing material coating data and design criteria to use coating as a design element,• increasing the fundamental understanding of the behaviour of coated materials, their degradation, fracture mechanisms and engineering because of the strong need for a mechanism-based modelling of durability.These programmes permitted the selection of two reference coatings and the development of two innovative coatings. Concurrently work has been done in order to develop corrosion, oxidation and thermo-mechanical property models. Correlations between coatings development, experimental results and calculations will be discussed.
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| 8. |
- Khodabandeh, Rahmatollah
(författare)
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Thermal performance of a closed advanced two-phase thermosyphon loop for cooling of radio base stations at different operating conditions
- 2004
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Ingår i: Applied Thermal Engineering. - : Elsevier BV. - 1359-4311 .- 1873-5606. ; 24:17-18, s. 2643-2655
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Tidskriftsartikel (refereegranskat)abstract
- ln this investigation an advanced thermosyphon loop with extended evaporator and condenser surfaces has been tested at high heat fluxes. The thermosyphon investigated is designed for the cooling of three parallel high heat flux electronic components. The tested evaporators were made from small blocks of copper in which five vertical channels with a diameter of 1.5 mm and length of 14.6 mm were drilled. The riser and downcomer connected the evaporators to the condenser, which is an air-cooled roll-bond type with a total surface area of 1.5 m(2) on the airside. Tests were done with Isobutane (R600a) at heat loads in the range of 10-90 W/cm(2) to each of the components with forced convection condenser cooling and with natural convection with heat loads of 10-70 W.
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| 9. |
- Martin, Andrew R., et al.
(författare)
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Energy analysis of impulse technology : research-scale experimental papermaking trials and simulations of industrial applications
- 2004
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Ingår i: Applied Thermal Engineering. - : Elsevier BV. - 1359-4311 .- 1873-5606. ; 24:16, s. 2411-2425
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Tidskriftsartikel (refereegranskat)abstract
- The impact of impulse technology on a system-wide level has been investigated in this study for non-integrated fine paper and linerboard mills. Impulse unit data were obtained from STFI's EuroFEX research paper machine and correlations were developed in order to predict performance (dewatering, electricity consumption) under commercial operating conditions. Mill analyses were conducted for different configurations (i.e. one or two impulse units with and without web preheating) operating with roll temperatures of 200-320 degreesC. Results show that the ingoing dryness to the dryer section can be increased within a wide span, from 7 to 27 percentage points depending upon the grade and operating parameters. Even though electricity consumption rises dramatically from the inductively heated rolls, overall fuel savings of up to 20% can be achieved with either one or two impulse units operating at 200 degreesC (external power plant efficiency assumed to be 45%). Impulse technology appears to be neutral in terms of production costs since increases in energy costs are expected to be counterbalanced by savings in feedstock materials and enhanced product quality. Estimates show that this technology can lead to substantial reductions in dryer section sizes for new installations or alternatively enhance productivity in existing paper machines.
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| 10. |
- Martin, Andrew R., et al.
(författare)
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Energy analysis of impulse technology : Research-scale experimental papermaking trials and simulations of industrial applications
- 2004
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Ingår i: Applied Thermal Engineering. - : Elsevier BV. - 1359-4311 .- 1873-5606. ; 24:16, s. 2411-2425
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Tidskriftsartikel (refereegranskat)abstract
- The impact of impulse technology on a system-wide level has been investigated in this study for non-integrated fine paper and linerboard mills. Impulse unit data were obtained from STFI's EuroFEX research paper machine and correlations were developed in order to predict performance (dewatering, electricity consumption) under commercial operating conditions. Mill analyses were conducted for different configurations (i.e. one or two impulse units with and without web preheating) operating with roll temperatures of 200-320 °C. Results show that the ingoing dryness to the dryer section can be increased within a wide span, from 7 to 27 percentage points depending upon the grade and operating parameters. Even though electricity consumption rises dramatically from the inductively heated rolls, overall fuel savings of up to 20% can be achieved with either one or two impulse units operating at 200 °C (external power plant efficiency assumed to be 45%). Impulse technology appears to be neutral in terms of production costs since increases in energy costs are expected to be counterbalanced by savings in feedstock materials and enhanced product quality. Estimates show that this technology can lead to substantial reductions in dryer section sizes for new installations or alternatively enhance productivity in existing paper machines.
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