Change search
Link to record
Permanent link

Direct link
BETA
Alternative names
Publications (10 of 35) Show all publications
Fakhrai, R. & Saadatfar, B. (2015). Feasibility study and quality assurance of the end-product of Alphakat KDV technology for conversion of biomass. KTH Royal Institute of Technology
Open this publication in new window or tab >>Feasibility study and quality assurance of the end-product of Alphakat KDV technology for conversion of biomass
2015 (English)Report (Other academic)
Abstract [sv]

För närvarande finns det ett stort intresse att utveckla ett ekonomiskt och framkomligt system för omvandling av biomassa till flytande bränslen och kemikalier, då hanteringen av bränslen väsentligt underlättas.

Under 2014, fick avdelningen för Energiteknik, KTH, uppdraget att undersöka och dokumentera KDVs process för konvertering av biomassa till flytande bränsle: Bland annat ingick att analysera processens produkt och restprodukter. Idag marknadsförs tekniken av Alphakat, Eppendorf, Tyskland. Alphakat gör gällande att KDV erbjuder en alternativ teknik för produktion av bränsle, inklusive syntetisk-diesel från fasta bränslen såsom biomassa. Det övergripande syftet med projektet var att samla information, tekniska data, processdata och genomföra test och analysera produkten. Detta för att få en uppfattning om huruvida KDV kan tekniskt användas föratt konvertera biomassa till diesel. Emellertid, KDVs tekniska potential, särskilt för omvandling av biomassa till flytande bränsle kunde inte bevisas baserat på resultaten av den nu aktuella undersökningen med den tillhandahållna informationen av företaget.

Produkten av processen analyserades enligt ASTM D6715. De relevanta egenskaperna för KDVs produkt dokumenterades genom noggranna tester. Men huruvida produkten kommer från biomassa kunde inte garanteras då KDV är en oljebaserad process. Påverkan av så kallade “Carrier oil”, på produktens kvalitet och kvantitet kan vara betydande då en stor del av värmevärdet hos bränslet kan komma från denna olja. KDVs potential för produktion av flytande bränsle från biomassa kan inte bevisas.

Vi bedömer att en fördjupad teknisk och vetenskaplig utvärdering av KDV är ett nödvändigt och viktigt steg för att framtiden underlätta kommande investeringar i KDVs teknologin. Denna utvärdering bör utföras i en laboratorieskala, med hjälp av avancerad mätutrustning, i en kontrollerad miljö som kunde garantera vetenskaplig dokumentation och övervakning av processen.

Förvätskning av biomassa ser vi som lovande då faktorer som medger attförnybara bränslen och kemikalier då kan göras tillgängliga för en allmän användning då de har en stor miljömässig fördel.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2015. p. 49
Keywords
Alphakat, KDV technology, Liquid fuel, Quality assurance, Conversion technology, Biomass, Swedish Energy Authority
National Category
Energy Engineering
Identifiers
urn:nbn:se:kth:diva-165583 (URN)KTH/KRV/15/01-SE (ISRN)
Funder
Swedish Energy Agency, 38565/1
Note

QC 20150603

Available from: 2015-04-29 Created: 2015-04-29 Last updated: 2016-07-07Bibliographically approved
Wei, B., Fakhrai, R. & Saadatfar, B. (2014). Catalytic CO2 conversion via solar-driven fluidized bed reactors. International Journal of Low-Carbon Technologies, 9(2), 127-134
Open this publication in new window or tab >>Catalytic CO2 conversion via solar-driven fluidized bed reactors
2014 (English)In: International Journal of Low-Carbon Technologies, ISSN 1748-1317, E-ISSN 1748-1325, Vol. 9, no 2, p. 127-134Article in journal (Refereed) Published
Abstract [en]

Converting CO2 and steam (H2O) into synthesis gas is a new route to recycle them to fuels. Conversions are performed via a two-step conversion method in which catalysts are heated up and cooled down repeatedly with CO and H2 as the products. To make the method economic, solar energy is employed to drive conversion systems. A solar-driven system with fluidized bed reactors is proposed for CO2 conversion in this paper, and numerical models are built to study its performance and find out the optimum working condition. The investigation proves that system is a competent candidate to power the two-step conversion of CO2 for the carbon recycle and the syngas production.

Keywords
Chemical reactors; Fluid catalytic cracking; Fluidized bed furnaces; Numerical models; Recycling; Solar energy; Synthesis gas, Conversion methods; Conversion systems; Fluidized bed reactors; Optimum working conditions; Syngas production; System assessment, Carbon dioxide
National Category
Energy Engineering
Identifiers
urn:nbn:se:kth:diva-153633 (URN)10.1093/ijlct/ctu018 (DOI)2-s2.0-84900528895 (Scopus ID)
Note

QC 20141006

Available from: 2014-10-06 Created: 2014-10-06 Last updated: 2017-12-05Bibliographically approved
Saadatfar, B., Fakhrai, R. & Fransson, T. (2014). Conceptual modeling of nano fluid ORC for solar thermal polygeneration. In: 2013 ISES SOLAR WORLD CONGRESS: . Paper presented at ISES Solar World Congress (SWC), NOV 03-07, 2013, Cancun, MEXICO (pp. 2696-2705). , 57
Open this publication in new window or tab >>Conceptual modeling of nano fluid ORC for solar thermal polygeneration
2014 (English)In: 2013 ISES SOLAR WORLD CONGRESS, 2014, Vol. 57, p. 2696-2705Conference paper, Published paper (Refereed)
Abstract [en]

A model has been developed for thermodynamic cycle of the solar thermal production of power, heating and cooling utilizing nano fluid as a working fluid in Organic Rankine Cycle. The proposed working fluid provides enhancement in power, heating, and cooling as useful outputs. Initial studies were performed with silver-nano pentane as a working fluid in the cycle. This work extends the application of the cycle to working fluids consisting of organic fluid mixtures. Nano Organic fluid could be used successfully in solar thermal power plants, as working fluids in Rankine cycles. An advantage of using nano fluid as a working fluid is that there are mature experiences with building components for these fluids. A commercially available modeling program has been used to model and investigate the performance of the system. The potential and advantages of using nano fluid are discussed. It is found that the thermodynamic efficiencies achievable with nano organic fluid, under optimum conditions, are higher than those obtained from the base fluid. Further, the size of heat exchangers, evaporator, and condenser are lower than those using the base fluid.

Series
Energy Procedia, ISSN 1876-6102
Keywords
Solar thermal, Organic Rankine Cycle, nano fluid ORC, polygeneration, nORC
National Category
Energy Engineering
Identifiers
urn:nbn:se:kth:diva-161589 (URN)10.1016/j.egypro.2014.10.301 (DOI)000348253202089 ()2-s2.0-84922318812 (Scopus ID)
Conference
ISES Solar World Congress (SWC), NOV 03-07, 2013, Cancun, MEXICO
Note

QC 20150325

Available from: 2015-03-25 Created: 2015-03-13 Last updated: 2015-03-25Bibliographically approved
Saadatfar, B., Fakhrai, R. & Fransson, T. (2014). Exergo-environmental analysis of nano fluid ORC low-grade waste heat recovery for hybrid trigeneration system. In: Energy Procedia: International Conference on Applied Energy, ICAE2014. Paper presented at 6th International Conference on Applied Energy, ICAE 2014, National Taiwan University of Science and Technology Taipei, Taiwan, 30 May 2014 through 2 June 2014 (pp. 1879-1882). Elsevier
Open this publication in new window or tab >>Exergo-environmental analysis of nano fluid ORC low-grade waste heat recovery for hybrid trigeneration system
2014 (English)In: Energy Procedia: International Conference on Applied Energy, ICAE2014, Elsevier, 2014, p. 1879-1882Conference paper, Published paper (Refereed)
Abstract [en]

In this work, a thermodynamic model based on theoretical and experimental data is developed for utilizing nano fluid organic Rankine cycle (nORC) in a trigeneration hybrid system. The trigeneration hybrid system composed of a solid biomass boiler, gas turbine cycle, a nORC, cooling, and a heating system. The exergy of the system analyzed; moreover, environmental impact assessments and interrelated parametric studies are examined. The results show higher exergy efficiency for the hybrid trigeneration employed nORC, and indicate that carbon dioxide emissions for utilizing nano fluid in nORC trigeneration system are less than conventional working fluid system.

Place, publisher, year, edition, pages
Elsevier, 2014
Series
Energy Procedia, ISSN 1876-6102 ; 61
National Category
Energy Engineering
Identifiers
urn:nbn:se:kth:diva-160676 (URN)10.1016/j.egypro.2014.12.233 (DOI)2-s2.0-84922341733 (Scopus ID)
Conference
6th International Conference on Applied Energy, ICAE 2014, National Taiwan University of Science and Technology Taipei, Taiwan, 30 May 2014 through 2 June 2014
Note

QC 20150226

Available from: 2015-02-26 Created: 2015-02-26 Last updated: 2015-02-26Bibliographically approved
Fakhrai, R., Saadatfar, B. & Fransson, T. (2014). Multi-disciplinary problem based learning in computational fluid dynamics. In: STAR Global Conference 2014, Vienna Austria: . Paper presented at STAR Global Conference 2014, Vienna Austria, March 17-19, 2014.
Open this publication in new window or tab >>Multi-disciplinary problem based learning in computational fluid dynamics
2014 (English)In: STAR Global Conference 2014, Vienna Austria, 2014Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

KTH Royal Institute of Technology (KTH) is one of European’s key centers of innovation and intellectual talent for almost two centuries. Recognized as Sweden’s most prestigious technical university, KTH is also the country’s oldest and largest. Computerized simulation technique was recognized as a fundamental component of the higher-education sector at KTH as early as the fifties. Although the utilization of these tools in research is now considered to be standard, the educational aspects are not. In this field, the method of instruction followed by practice is considered to be a superior pedagogic method compared to lecture to many. The current method emphasizes on demonstrative activities of the learners known as phenomeno-graphic learning. However, phenomeno-graphic learning is viable if there are breadth and depth in the physic, mathematic, computer science and graphic, operational strategy and methodology, etc. illuminating weakness of learning by doing method.  

This work aims to report the success and progress of the course, numerical methods in energy technology, which utilizes Computational Fluid Dynamics cods such as STAR-CCM+ as the tool. Learning methodology is based on instructional design and andragogically approach that offers an elaboration on the mechanism of learning process and its premeditated in context of a prescribed framework. The results indicated the prominence of student sensitive and constructive learning process and the advantages of using a preferred framework in guiding the students in a pertinent context (area). The method particularly incorporates the constructivist principles that lead to enhance the learning process. In addition, the conclusions of this study similarly illuminate the vast potentials of computational fluid dynamic for research, evaluation and educational purposes.

Keywords
Multi disciplinary learning, PBL learning, CFD, computational fluid dynamics
National Category
Educational Sciences
Identifiers
urn:nbn:se:kth:diva-166239 (URN)
Conference
STAR Global Conference 2014, Vienna Austria, March 17-19, 2014
Note

QC 20150506

Available from: 2015-05-06 Created: 2015-05-06 Last updated: 2015-05-06Bibliographically approved
Wei, B., Fakhrai, R., Saadatfar, B., Mohan, G. & Fransson, T. (2014). The design of a solar-driven catalytic reactor for CO2 conversions. Energy Procedia, 57, 2752-2761
Open this publication in new window or tab >>The design of a solar-driven catalytic reactor for CO2 conversions
Show others...
2014 (English)In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 57, p. 2752-2761Article in journal (Refereed) Published
Abstract [en]

The solar energy has been employed to provide the heat for CO2 conversions for several years except for its use on power generation, since it is one of the most common renewable energy resources and the total amount is enormous; However, the dominant method is to concentrate solar rays directly on reactants, relying on the design and quality of the receivers a lot. The operation and maintenance of the receivers require extra attention due to the delicate structure of the receivers and the potential contamination on the lenses from the chemical reactions. To steer clear of the shortcoming, a solar-driven catalytic reactor has been designed and analyzed in this article. The reactor drives the endothermic reactions with the heat source of hot gases, which are produced in solar receivers upriver, thus the flexible and necessary operations on the catalytic reactor could be peeled off from the solar receiver, and the potential contamination on the optical components in the solar receiver could be avoided. The design processes and details are described, the heat performance is simulated and analyzed, and efficiencies are theoretically calculated in this article. The solar-driven catalytic reactor exhibits the possibility of the practical use of solar energy in CO2 conversion and recycle.

National Category
Energy Engineering
Identifiers
urn:nbn:se:kth:diva-153644 (URN)10.1016/j.egypro.2014.10.307 (DOI)000348253202095 ()2-s2.0-84921990102 (Scopus ID)
Note

Updtated from accepted to published.

Available from: 2014-10-06 Created: 2014-10-06 Last updated: 2017-12-05Bibliographically approved
Wei, B., Fakhrai, R. & Saadatfar, B. (2014). The thermodynamic analysis of two-step conversions of CO2/H2O for syngas production by ceria. International journal of hydrogen energy, 39(23), 12353-12360
Open this publication in new window or tab >>The thermodynamic analysis of two-step conversions of CO2/H2O for syngas production by ceria
2014 (English)In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 39, no 23, p. 12353-12360Article in journal (Refereed) Published
Abstract [en]

Due to the challenges of demands on alternative fuels and CO2 emission, the conversion of CO2 has become a hot spot. Among various methods, two-step conversion of CO2 with catalyst ceria (cerium oxide, CeO2) appears to be a promising way. Solar energy is commonly employed to drive the conversion systems. This article proposes a solar-driven system with fluidized bed reactors (PER) for CO2/H2O conversions. N-2 is used as the gas of the heat carrier. The products of CO/H-2 could be further used for syngas. To evaluate the capability of the system for exporting work, the system was analysed on the basis of the Second Law of Thermodynamics and the reaction mechanism of ceria. Heat transfer barriers in practical situations were considered. The lowest solar to chemical efficiency is 4.86% for CO2 conversion, and can be enhanced to 43.2% by recuperating waste heat, raising the N-2 temperature, and increasing the concentration ratio. The analysis shows that the method is a promising approach for CO2/H2O conversion to produce syngas as an alternative fuel.

Keywords
Thermodynamic analysis, CO2 conversion, CeO2, Solar energy, Syngas
National Category
Energy Engineering
Identifiers
urn:nbn:se:kth:diva-150930 (URN)10.1016/j.ijhydene.2014.03.250 (DOI)000340328800059 ()2-s2.0-84904727862 (Scopus ID)
Note

QC 20140912

Available from: 2014-09-12 Created: 2014-09-11 Last updated: 2017-12-05Bibliographically approved
Leifsson, L., Koziel, S., Hermannsson, E. & Fakhraie, R. (2014). Trawl-door design optimization by local surrogate models. In: 55th AIAA/ASMe/ASCE/AHS/SC Structures, Structural Dynamics, and Materials Conference: . Paper presented at 55th AIAA/ASMe/ASCE/AHS/SC Structures, Structural Dynamics, and Materials Conference - SciTech Forum and Exposition 2014; National Harbor, MD; United States; 13 January 2014 through 17 January 2014.
Open this publication in new window or tab >>Trawl-door design optimization by local surrogate models
2014 (English)In: 55th AIAA/ASMe/ASCE/AHS/SC Structures, Structural Dynamics, and Materials Conference, 2014Conference paper, Published paper (Refereed)
Abstract [en]

Trawl-doors have a large influence on the fuel consumption of fishing vessels. Design and optimization of trawl-doors using computational models are a key factor in minimizing the fuel consumption. This paper presents an optimization algorithm for the shape design of trawl-door shapes using computational fluid dynamic (CFD) models. Accurate CFD models are computationally expensive. Therefore, the direct use of traditional optimization algorithms, which often require a large number of evaluations, may prohibitive. The proposed approach is iterative and uses low-order local response surface approximation models of the expensive CFD model, constructed in each iteration, to reduce the number of evaluations. The algorithm is applied to the design of a two-element trawl-door (slat and airfoil), involving four design variables controlling the angle of attack and the slat position and orientation. The results show that a satisfactory design can be obtained at the cost of a few iterations of the algorithm.

National Category
Engineering and Technology
Identifiers
urn:nbn:se:kth:diva-145456 (URN)10.2514/6.2014-0574 (DOI)2-s2.0-84894456399 (Scopus ID)
Conference
55th AIAA/ASMe/ASCE/AHS/SC Structures, Structural Dynamics, and Materials Conference - SciTech Forum and Exposition 2014; National Harbor, MD; United States; 13 January 2014 through 17 January 2014
Note

QC 20140522

Available from: 2014-05-22 Created: 2014-05-21 Last updated: 2014-05-22Bibliographically approved
Reza, F., Bahram, S. & Fransson, T. (2013). Conceptual Model for Educational Deployment of Podcast in Context of Learning Process Enhancement. In: INTED2013 Proceedings: 7th International Technology, Education and Development Conference Valencia, Spain. 4-5 March, 2013.. Paper presented at 7th International Technology, Education and Development Conference Valencia, Spain. 4-5 March, 2013. (pp. 1716-1719). IATED
Open this publication in new window or tab >>Conceptual Model for Educational Deployment of Podcast in Context of Learning Process Enhancement
2013 (English)In: INTED2013 Proceedings: 7th International Technology, Education and Development Conference Valencia, Spain. 4-5 March, 2013., IATED , 2013, p. 1716-1719Conference paper, Published paper (Refereed)
Abstract [en]

Research has shown that learners are progressively more emphasizing on the importance of communication platform in learning and teaching along with convenience and flexibility, to accommodate the needs of their active lifestyles. In other words, learners are looking for an educational system to deliver in a relevant manner that is technology-enhanced. New technologies, Information and Communications Technology have made sizable evolution and generated impact and improvement over the conditions for learning in education, training and Lifelong Learning (LLL).

To deal with the issues that are created by this changing landscape, a research project created across a course to review the use, effectiveness and impact of the podcast across teaching and learning scenarios and services. It was structured around some specific items: creation, deployment and impact. The output of this study illuminates the significant potentials of using podcast in learning process, intended learning outcomes as well as describes a conceptual framework used by integrating podcast into learning process.

Place, publisher, year, edition, pages
IATED, 2013
Keywords
podcast, learning process enhancement, learning outcome, life long learning, e-learning
National Category
Educational Sciences
Identifiers
urn:nbn:se:kth:diva-165814 (URN)000346699801109 ()978-84-616-2661-8 (ISBN)
Conference
7th International Technology, Education and Development Conference Valencia, Spain. 4-5 March, 2013.
Note

QC 20150504

Available from: 2015-05-01 Created: 2015-04-29 Last updated: 2015-12-03Bibliographically approved
Zhang, X., Jayasuriya, J., Fakhraie, R. & Fransson, T. (2013). Evaluation of reduced kinetics in simulation of gasified biomass gas combustion. In: ASME Turbo Expo 2013: Turbine Technical Conference and Exposition: Volume 1B: Combustion, Fuels and Emissions. Paper presented at ASME Turbo Expo 2013: Turbine Technical Conference and Exposition, GT 2013, San Antonio, Tx, United States, 3 June 2013 through 7 June 2013 (pp. V01BT04A045). ASME Press, 1B
Open this publication in new window or tab >>Evaluation of reduced kinetics in simulation of gasified biomass gas combustion
2013 (English)In: ASME Turbo Expo 2013: Turbine Technical Conference and Exposition: Volume 1B: Combustion, Fuels and Emissions, ASME Press, 2013, Vol. 1B, p. V01BT04A045-Conference paper, Published paper (Refereed)
Abstract [en]

It is essentially important to use appropriate chemical kinetic models in the simulation process of gas turbine combustion. To integrate the detailed kinetics into complex combustion simulations has proven to be a computationally expensive task with tens to thousands of elementary reaction steps. It has been suggested that an appropriate simplified kinetics which are computationally efficient could be used instead. Therefore reduced kinetics are often used in CFD simulation of gas turbine combustion. At the same time, simplified kinetics for specific fuels and operation conditions need to be carefully selected to fulfill the accuracy requirements. The applicability of several simplified kinetics for premixed Gasified Biomass Gas (GBG) and air combustion are evaluated in this paper. The current work is motivated by the growing demand of gasified biomass gas (GBG) fueled combustion. Even though simplified kinetic schemes developed for hydrocarbon combustions are published by various researchers, there is little research has been found in literature to evaluate the ability of the simplified chemical kinetics for the GBG combustion. The numerical Simulation tool "CANTERA" is used in the current study for the comparison of both detailed and simplified chemical kinetics. A simulated gas mixture of CO/H2/CH4/CO2/N2 is used for the current evaluation, since the fluctuation of GBG components may have an unpredictable influence on the simulation results. The laminar flame speed has an important influence with flame stability, extinction limits and turbulent flame speed, here it is chosen as an indicator for validation. The simulation results are compared with the experimental data from the previous study [1] which is done by our colleagues. Water vapour which has shown a dilution effect in the experimental study are also put into concern for further validation. As the results indicate, the reduced kinetics which are developed for hydrocarbon or hydrogen combustion need to be highly optimized before using them for GBG combustion. Further optimization of the reduced kinetics is done for GBG and moderate results are achieved using the optimized kinetics compared with the detailed combustion kinetics.

Place, publisher, year, edition, pages
ASME Press, 2013
Keywords
Chemical kinetic model, Combustion simulations, Computationally efficient, Gas-turbine combustion, Hydrocarbon combustion, Hydrogen combustion, Operation conditions, Turbulent flame speed
National Category
Energy Engineering
Identifiers
urn:nbn:se:kth:diva-166249 (URN)10.1115/GT2013-95565 (DOI)2-s2.0-84890180038 (Scopus ID)978-079185511-9 (ISBN)
Conference
ASME Turbo Expo 2013: Turbine Technical Conference and Exposition, GT 2013, San Antonio, Tx, United States, 3 June 2013 through 7 June 2013
Note

QC 20150511

Available from: 2015-05-06 Created: 2015-05-06 Last updated: 2015-06-03Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-2992-6814

Search in DiVA

Show all publications