Selaus tekijän mukaan kokoelmassa "Backman, Jari"Tieteelliset julkaisut

Aineistot 1-11 / 11

    • A high efficiency microturbine concept 

      Malkamäki, Matti; Jaatinen-Värri, Ahti; Honkatukia, Ahti; Backman, Jari; Larjola, Jaakko (2015)
      There is a growing trend towards decentralized electricity and heat production throughout the world. Reciprocating engines and gas turbines have an essential role in the global decentralized energy markets and any improvement ...

    • Centrifugal compressor tip clearance and impeller flow 

      Jaatinen-Värri, Ahti; Tiainen, Jonna; Turunen-Saaresti, Teemu; Grönman, Aki; Ameli, Alireza; Engeda, Abraham; Backman, Jari (Springer Verlag, 2016)
      Compressors consume a considerable portion of the electricity used in the industrial sector. Hence, improvements in compressor efficiencylead to energy savings and reduce environmental impacts. The efficiency of an unshrouded ...

    • Design and verification of a hermetic high-speed turbogenerator concept for biomass and waste heat recovery applications 

      Grönman, Aki; Nerg, Janne; Sikanen, Eerik; Sillanpää, Teemu; Nevaranta, Niko; Scherman, Eero; Uusitalo, Antti; Uzhegov, Nikita; Smirnov, Alexander; Honkatukia, Juha; Sallinen, Petri; Jastrzebski, Rafal; Heikkinen, Janne; Backman, Jari; Pyrhönen, Juha; Pyrhönen, Olli; Sopanen, Jussi; Turunen-Saaresti, Teemu (Elsevier, 11.09.2020)
      Many waste heat recovery and biomass applications offer opportunities for small-scale steam turbines to produce electricity and to improve systems’ energy efficiency. However, the currently used axial turbine-based technology ...

    • Effects of Different Blade Angle Distributions on Centrifugal compressor performance 

      Röyttä, Pekka; Grönman, Aki; Jaatinen, Ahti; Turunen-Saaresti, Teemu; Backman, Jari (Hindawi, 2009)
      A centrifugal compressor with three different shrouded 2D impellers is studied numerically. All impellers have the same dimensions, and they only differ in channel length and geometry. Noticeable differences in efficiency ...

    • Experimental study of centrifugal compressor tip clearance and vaneless diffuser flow fields 

      Jaatinen-Värri, Ahti; Turunen-Saaresti, Teemu; Röyttä, Pekka; Grönman, Aki; Backman, Jari (Sage Journals, 2013)
      Three vaneless diffuser designs, varying in diffuser width, for centrifugal compressor were studied experimentally. Along with the diffuser width, the tip clearance was altered. The compressor overall performance and ...

    • Flow Control Methods and Their Applicability in Low-Reynolds-Number Centrifugal Compressors—A Review 

      Tiainen, Jonna; Grönman, Aki; Jaatinen-Värri, Ahti; Backman, Jari (MDPI, 2018)
      The decrease in the performance of centrifugal compressors operating at low Reynolds numbers (e.g., unmanned aerial vehicles at high altitudes or small turbomachines) can reach 10% due to increased friction. The purposes ...

    • Importance of the vane exit mach number on the axial clearance-related losses 

      Grönman, Aki; Biester, Marc H.-O.; Turunen-Saaresti, Teemu; Jaatinen-Värri, Ahti; Backman, Jari; Seume, Jörg R. (Sage Journals, 2016)
      More efficient and physically smaller axial turbine designs are promoted to lower emissions and increase revenue. The physical size and the weight of the axial turbine can be minimised by adjusting the distance between ...

    • Investigation of the Stage Performance and Flow Fields in a Centrifugal Compressor with a Vaneless Diffuser 

      Jaatinen-Värri, Ahti; Grönman, Aki; Turunen-Saaresti, Teemu; Backman, Jari (Hindawi, 2014)
      The effect of the width of the vaneless diffuser on the stage performance and flow fields of a centrifugal compressor is studied numerically and experimentally. The diffuser width is varied by reducing the diffuser flow ...

    • Loss Development Analysis of a Micro-Scale Centrifugal Compressor 

      Tiainen, Jonna; Jaatinen-Värri, Ahti; Grönman, Aki; Fischer, Tore; Backman, Jari (Elsevier, 2018)
      The ever-increasing demand for more efficient energy conversion has placed designers under increasing pressure to develop processing equipment that can meet contemporary needs. It has long been known that a decreasing ...

    • Modelling of Low-Reynolds-Number Centrifugal Compressors: Challenges in Performance and Flow Control Prediction 

      Tiainen, Jonna; Grönman, Aki; Jaatinen-Värri, Ahti; Backman, Jari (2018)
      A low-Reynolds-number causes a performance deterioration in centrifugal compressors due to the relative increase in boundary layer thickness, tip clearance, and surface roughness. The degradation of the efficiency can be ...

    • Performance and flow fields of a supersonic axial turbine at off-design conditions 

      Grönman, Aki; Turunen-Saaresti, Teemu; Röyttä, Pekka; Jaatinen, Ahti; Backman, Jari (Institution of Mechanical Engineers, 2013)
      The increasing demand of energy efficiency and the utilisation of small-scale energy sources require efficient, small and versatile turbines. Supersonic turbines have a high power density and therefore small size and fewer ...