Jürg Alexander Schiffmann
Domaines de compétences
Small scale turbomachinery
Gas lubricated bearings
Organic Rankine Cycles
BiographieAfter obtaining his diploma in mechanical engineering from EPFL in 1999 he co-founded a start-up company dedicated to the design of gas bearing supported rotors. In 2005 he joined Fischer Engineering Solutions where he led the development of small-scale, gas bearing supported high-speed turbomachinery for fuel cell air supplies and for domestic scale heat pumps. In parallel he worked on his PhD, which he obtained from EPFL in 2008 and for which he was awarded the SwissElectric Research Award. He then joined the Gas Turbine Lab at MIT as a postdoctoral associate where he worked on foil bearings and on the experimental investigation of radial diffusers. In 2013 he was nominated assistant professor at the Ecole Polytechnique Fédérale de Lausanne where he founds the Laboratory for Applied Mechanical Design. His current research interest are in gas lubricated bearings, in aerodynamics of small-scale compressors and turbines and in automated design and optimization methodologies.
Modelling and Sensors for Magnetically-Levitated Disc DrivesLausanne, EPFL, 2022. DOI : 10.5075/epfl-thesis-8837.
Stability and Unbalance Analysis of Rigid Rotors Supported by Spiral Groove Bearings: Comparison of Different ApproachesJournal of Engineering for Gas Turbines and Power. 2021-12-01. DOI : 10.1115/1.4052025.
A reduced order model to predict the machining time and cost of small-scale radial-inflow turbines2021-11-04. 6th International Seminar on ORC Power Systems (ORC2021), Munich, Germany, October 11-13, 2021.
The effects of the tip clearance on the performance of small-scale turbopumps for ORC applications; analysis and modeling2021-11-04. 6th International Seminar on ORC Power Systems (ORC2021), Munich, Germany, October 11-13, 2021.
Experimental Investigation of a Small-Scale Organic Rankine Cycle Turbo-Generator Supported on Gas-Lubricated BearingsJournal of Engineering for Gas Turbines and Power. 2021-03-11. DOI : 10.1115/1.4049988.
Theoretical and Experimental Investigation of a 34 Watt Radial-Inflow Steam Turbine with Partial-Admission2021-01-11. ASME Turbo Expo: Turbomachinery Technical Conference and Exposition, London, England - virtual conference, June 22-26, 2020. p. GT2020-15804, V008T20A023. DOI : 10.1115/GT2020-15804.
Influence of Large Relative Tip Clearances for a Micro Radial Fan and Design Guidelines for Increased Efficiency2021-01-11. ASME Turbo Expo: Turbomachinery Technical Conference and Exposition, London, England - virtual conference, June 22-26, 2020. p. GT2020-15994, V008T20A025. DOI : 10.1115/GT2020-15994.
Automated Design Tool for Automotive Control Actuators2020-11-03. 46th Design Automation Conference (DAC), Virtual, Online, August 17–19, 2020. DOI : 10.1115/DETC2020-22390.
Actuator Synthesis and Optimization: Evaluation of Graph-Based Approaches2020-06-19
Experimental and Numerical Investigation of a Small-Scale Steam Turbine2020-01-01
Sofc system with anode off-gas recirculationEP3834244 ; WO2020030796 ; EP3609006 . 2020.
Scale limitations of gas bearing supported turbocompressors for vapor compression cyclesInternational Journal of Refrigeration. 2020-01-01. DOI : 10.1016/j.ijrefrig.2019.09.019.
An Instrumented High-Speed Rotor With Embedded Telemetry For The Continuous Spatial Pressure Profile Measurement In Gas Lubricated Bearings: A Proof Of Concept2019-11-05. ASME Turbo Expo: Turbomachinery Technical Conference and Exposition, Phoenix, AZ, Jun 17-21, 2019. p. V07BT34A026.
High temperature heat pumps – Theoretical study on low GWP HFO and HCFO refrigerants2019-08-25. ICR 2019 - The 25th IIR International Congress of Refrigeration, Montréal, Québec, Canada, August 24-30, 2019.
High temperature heat pump using HFO and HCFO refrigerants – system design and experimental results2019-08-25. ICR 2019 - The 25th IIR International Congress of Refrigeration, Montréal, Québec, Canada, August 24-30, 2019.
Theoretical and Experimental Investigation of a Small-Scale, High-Speed, and Oil-Free Radial Anode Off-Gas Recirculation Fan for Solid Oxide Fuel Cell Systems2019-06-17. ASME Turbo Expo 2019, Phoenix AZ, USA, June 17-21, 2019. p. GT2019-91361. DOI : 10.1115/GT2019-91361.
Impact of large tip clearance ratios on the performance of a centrifugal compressor2019-04-08. Euro Turbo Conderence ETC13, Lausanne, Switzerland, April 8-12, 2019.
Assessing student learning of design and project management skills in a project-based courseSFDN Conference 2019, Zurich, Switzerland.
Two-phase and oil-free co-rotating scroll compressor/expanderApplied Thermal Engineering. 2019-02-05. DOI : 10.1016/j.applthermaleng.2018.11.037.
Analytical and Numerical Investigation of a Small-scale Radial-Inflow Steam Turbine2019-01-31
Pressure Profile Measurements Within The Gas Film Of Journal Foil Bearings Using An Instrumented Rotor With Telemetry2019. ASME Turbo Expo: Turbomachinery Technical Conference and Exposition, Phoenix, AZ, Jun 17-21, 2019.
Data-Driven Predesign Tool for Small-Scale Centrifugal Compressor in RefrigerationJournal of Engineering for Gas Turbines and Power. 2018-10-24. DOI : 10.1115/1.4040845.
High Temperature Heat Pumps: Market Overview, Stateof the Art, Research Status, Refrigerants, and Application Potentials2018-07-09. 17th International Refrigeration and Air Conditioning Conference, Purdue, USA, July 9-12, 2018. p. 2200, Page 1-10.
Small, High-Speed, Oil-Free Radial Turbo-compressors for Cooling Applications: Refrigerant Selection2018-07-09. 24 th International Compressor Engineering Conference, Purdue, USA, July 9-12, 2018. p. 2386, pages 1-10.
High temperature heat pump using HFO and HCFO refrigerants – System design, simulation, and first experimental results2018-07-09. 17 th International Refrigeration and Air Conditioning Conference at Purdue, Purdue, USA, July 9-12, 2018.
Data-Driven Pre-Design Tool for Small Scale Centrifugal Compressors in Refrigeration2018-06-11. ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition, Oslo, Norway, June 11-15, 2018. p. V008T26A012. DOI : 10.1115/GT2018-76349.
A co-rotational scroll machineUS2021062807 ; EP3740679 ; CN111630277 ; WO2018134739 . 2018.
High temperature heat pumps: Market overview, state of the art, research status, refrigerants, and application potentialsEnergy. 2018. DOI : 10.1016/j.energy.2018.03.166.
Dynamic pressure probe response tests for robust measurements in periodic flows close to probe resonating frequencyMeasurement Science and Technology. 2018. DOI : 10.1088/1361-6501/aa9cf4.
Small scale radial inflow turbine performance and pre-design maps for Organic Rankine CyclesEnergy. 2018. DOI : 10.1016/j.energy.2017.11.002.
Blade Tio Loss in a Small-Scale Fan2017-06-09
Comparative Evaluation of Foil Bearings with Different Compliant Structures for Improved Manufacturability2017. ASME Turbo Expo, Charlotte, North Carolina, USA, June 26-30, 2017. p. V07AT34A014. DOI : 10.1115/GT2017-63615.
Thermo-economic optimization of an ORC driven heat pump based on small scale turbomachinery and comparison with absorption heat pumpsInternational Journal of Refrigeration. 2017. DOI : 10.1016/j.ijrefrig.2017.05.021.
Heat Pump driven by a Small-Scale Oil-Free Turbocompressor – System Design and Simulation2017. 12th IEA Heat Pump Conference 2017, Rotterdam, Netherlands, May 14-18, 2017.
ORC Driven Heat Pump Running on Gas Bearings for Domestic Applications: Proof of Concept and Thermo-Economic Improvement Potential2017. 12th IEA heat Pump Conference 2017, Rotterdam, Netherlands, May 14-18, 2017.
Theoretical analysis of steam generation methods - Energy, CO 2 emission, and cost analysisEnergy. 2017. DOI : 10.1016/j.energy.2017.04.088.
Turbocompressors for Domestic Heat Pumps – A Critical Review2017. 12th IEA Heat Pump Conference 2017, Rotterdam, Netherlands, May 14-18, 2017.
The Role of Impeller Outflow Conditions on the Performance of Vaned DiffusersJournal of Turbomachinery. 2017. DOI : 10.1115/1.4035048.
Testing and modelling of a novel oil-free co-rotating scroll machine with water injectionApplied Energy. 2017. DOI : 10.1016/j.apenergy.2016.10.089.
Theoretical Study of a Novel Oil-Free Co-Rotating Scroll Compressor Integrated into a Hybrid Absorption Heat Pumps2016. 12th IIR-Gustav Lorentzen Conference on Natural Refrigerants, Edinburgh, UK, 21st-24th August 2016.
Analysis of a Combined Absorption Cycle for Power and Cooling Production Using a Novel Oil-Free Co-Rotating Scroll Expander2016. 12th IIR-Gustav Lorentzen Conference on Natural Refrigerants, Edinburgh, UK, 21st-24th August 2016.
Multi-temperature heat pumps: A literature reviewInternational Journal Of Refrigeration-Revue Internationale Du Froid. 2016. DOI : 10.1016/j.ijrefrig.2016.05.014.
Two-Stage Heat Pump using Oil-Free Turbocompressors – System Design and Simulation2016. 16 th International Refrigeration and Air Conditioning Conference at Purdue, Purdue, West Lafayette, USA, July 11-14, 2016.
Experimental investigation of a two-stage oil-free domestic Air/Water heat pump prototype powered by an oil-free high-speed twin-stage radial compressor rotating on gas bearings2016. 16 th International Refrigeration and Air Conditioning Conference at Purdue, Purdue, West Lafayette, USA, July 11-14, 2016.
Multi-Temperature Heat Pumps - A Literature Review2016. 16 th International Refrigeration and Air Conditioning Conference at Purdue, Purdue, West Lafayette, USA, July 11-14, 2016.
Design of Oil-Free Turbocompressors for a Two-Stage Industrial Heat Pump under Variable Operating Conditions2016. 23 rd International Compressor Engineering Conference at Purdue, Purdue, West Lafayette, USA, July 11-14, 2016.
Small-scale turbocompressors for wide-range operation with large tip-clearances for a two-stage heat pump conceptInternational Journal of Refrigeration. 2016. DOI : 10.1016/j.ijrefrig.2016.06.015.
THE ROLE OF IMPELLER OUTFLOW CONDITIONS ON THE PERFORMANCE OF VANED DIFFUSERS2016. ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition, Seoul, South Korea, June 13 – 17, 2016.
Enseignement & Phd
Doctoral Program in Energy
Doctoral Program in Microsystems and Microelectronics
Doctoral program in advanced manufacturing
Doctoral program in robotics, control, and intelligent systems
Doctoral Program in Mechanics