研究成果 1986 2020

2015

Large-scale numerical simulation of unsteady flow field in a half-ducted propeller fan using lattice Boltzmann method

Yamada, K., Kusano, K. & Furukawa, M., 1 1 2015.

研究成果: 会議への寄与タイプ論文

Acoustic fields
Propellers
Unsteady flow
Fans
Flow fields
8 引用 (Scopus)

Measurements of axial and radial thrust forces working on a three-stages centrifugal pump rotor

Yamashita, T., Watanabe, S., Hara, Y., Watanabe, H. & Miyagawa, K., 1 1 2015.

研究成果: 会議への寄与タイプ論文

Centrifugal pumps
Rotors
Flow rate
Ball bearings
Journal bearings

Measurement technique for unsteady low-speed flow fields using poly(TMSP)-based pressure sensitive paint

Mori, H., Maeda, K., Furukawa, M. & Akiyoshi, M., 1 1 2015.

研究成果: 会議への寄与タイプ論文

Paint
Flow fields
Polymers
Oxygen
Quenching

Numerical analysis of unsteady three-dimensional flow in a propeller fan using multi-scale lattice boltzmann method

Kusano, K., Yamada, K. & Furukawa, M., 1 1 2015, FAN 2015 - International Conference on Fan Noise, Technology and Numerical Methods. Institution of Mechanical Engineers, 巻 2015-April.

研究成果: 著書/レポートタイプへの貢献会議での発言

propeller fans
three dimensional flow
numerical analysis
simulation
computational grids

Numerical investigation of influence of rotor-rotor gap on performances of contra-rotating axial flow pump

Cao, L., Watanabe, S., Furukawa, A. & Wu, D., 1 1 2015, Symposia. American Society of Mechanical Engineers, (ASME/JSME/KSME 2015 Joint Fluids Engineering Conference, AJKFluids 2015; 巻数 1).

研究成果: 著書/レポートタイプへの貢献会議での発言

Axial flow
Rotors
Pumps
Hydraulics
Turbomachine blades

Numerical investigation on performance of contra-rotating axial flow pump with different rear rotor design

Honda, H., Cao, L., Watanabe, S., Tsuda, S. I. & Furukawa, A., 1 1 2015.

研究成果: 会議への寄与タイプ論文

Axial flow
Rotors
Pumps
Secondary flow
Computer simulation
3 引用 (Scopus)

Validation of Bubble Dynamics Equation for a Nano-scale Bubble via Molecular Dynamics Simulation

Tsuda, S., Hyodo, H. & Watanabe, S., 12 3 2015, : : Journal of Physics: Conference Series. 656, 1, 012039.

研究成果: ジャーナルへの寄稿Conference article

bubbles
molecular dynamics
Rayleigh equations
simulation
noncondensable gases
2014
2 引用 (Scopus)

Effect of runner position on performance for open type cross-flow turbine utilizing waterfalls

Katayama, Y., Iio, S. & Veerapun, S., 11 1 2014, : : International Review of Mechanical Engineering. 8, 6, p. 1012-1016 5 p.

研究成果: ジャーナルへの寄稿記事

Turbines
Water
Hydraulic turbines
Flow rate
5 引用 (Scopus)

Experimental and numerical investigations on performances of Darriues-type hydro turbine with inlet nozzle

Matsushita, D., Tanaka, K., Watanabe, S., OKuma, K. & Furukawa, A., 1 1 2014, : : International Journal of Fluid Machinery and Systems. 7, 4, p. 151-159 9 p.

研究成果: ジャーナルへの寄稿記事

Intake systems
Nozzles
Turbines
Nozzle design
Computer simulation
4 引用 (Scopus)

Experimental investigation of blade rows interactions in contrarotating axial flow pump

Cao, L., Honda, H., Yoshimura, H., Watanabe, S. & Furukawa, A., 1 1 2014, Symposia: Fluid Machinery; Fluid-Structure Interaction and Flow-Induced Noise in Industrial Applications; Flow Applications in Aerospace; Flow Manipulation and Active Control: Theory, Experiments and Implementation; Multiscale Methods for Multiphase Flow; Noninvasive Measurements in Single and Multiphase Flows. American Society of Mechanical Engineers (ASME), (American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FEDSM; 巻数 1B).

研究成果: 著書/レポートタイプへの貢献会議での発言

Axial flow
Turbomachine blades
Rotors
Pumps
Pressure measurement
2 引用 (Scopus)

Experimental investigation of blade-to-blade pressure distribution in contra-rotating axial flow pump

Cao, L., Watanabe, S., Honda, H., Yoshimura, H. & Furukawa, A., 1 1 2014, : : International Journal of Fluid Machinery and Systems. 7, 4, p. 130-141 12 p.

研究成果: ジャーナルへの寄稿記事

Axial flow
Pressure distribution
Turbomachine blades
Rotors
Pumps
4 引用 (Scopus)

Simultaneous optimization of rotor blade and wind-lens for aerodynamic design of wind-lens turbine

Oka, N., Furukawa, M., Yamada, K., Kawamitsu, K., Kido, K. & Oka, A., 1 1 2014, ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, GT 2014. American Society of Mechanical Engineers (ASME), (Proceedings of the ASME Turbo Expo; 巻数 3B).

研究成果: 著書/レポートタイプへの貢献会議での発言

Turbomachine blades
Lenses
Aerodynamics
Turbines
Rotors
1 引用 (Scopus)

Suppression of secondary flows in an axial flow turbine rotor with a novel blade design concept

Yamada, K., Furukawa, M., Shibata, T., Nakakido, S. & Oka, N., 1 1 2014, Turbomachinery. American Society of Mechanical Engineers (ASME), (Proceedings of the ASME Turbo Expo; 巻数 2C).

研究成果: 著書/レポートタイプへの貢献会議での発言

Cambers
Axial flow
Secondary flow
Turbomachine blades
Turbines
1 引用 (Scopus)

Tentative study on performance of darriues-type hydroturbine operated in small open water channel

Matsushita, D., Moriyama, R., Nakashima, K., Watanabe, S., Okuma, K. & Furukawa, A., 1 1 2014, : : IOP Conference Series: Earth and Environmental Science. 22, 062007.

研究成果: ジャーナルへの寄稿Conference article

open water
turbine
torque
water level
channel flow
2 引用 (Scopus)

Thermal and dissolved gas effects on cavitation in a 2-D convergent-divergent nozzle flow

Watanabe, S., Enomoto, K., Yamamoto, Y. & Hara, Y., 1 1 2014, Fora: Cavitation and Multiphase Flow; Fluid Measurements and Instrumentation; Microfluidics; Multiphase Flows: Work in Progress; Fluid-Particle Interactions in Turbulence. American Society of Mechanical Engineers (ASME), (American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FEDSM; 巻数 2).

研究成果: 著書/レポートタイプへの貢献会議での発言

Cavitation
Nozzles
Thermal effects
Gases
Ethers
3 引用 (Scopus)

Unsteady lift and drag characteristics of cavitating Clark Y-11.7% hydrofoil

Watanabe, S., Yamaoka, W. & Furukawa, A., 1 1 2014, : : IOP Conference Series: Earth and Environmental Science. 22, 052009.

研究成果: ジャーナルへの寄稿Conference article

drag
cavity
oscillation
cavitation
unsteady flow
2013
6 引用 (Scopus)

Aerodynamic design for wind-lens turbine using optimization technique

Oka, N., Furukawa, M., Yamada, K. & Kido, K., 12 1 2013, ASME 2013 Fluids Engineering Division Summer Meeting, FEDSM 2013. V01AT02A009. (American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FEDSM; 巻数 1 A).

研究成果: 著書/レポートタイプへの貢献会議での発言

Lenses
Aerodynamics
Turbines
Rotors
Viscous flow
6 引用 (Scopus)

A study on Darrieus-type hydroturbine toward utilization of extra-low head natural flow streams

Tanaka, K., Hirowatari, K., Shimokawa, K., Watanabe, S., Matsushita, D. & Furukawa, A., 10 4 2013, : : International Journal of Fluid Machinery and Systems. 6, 3, p. 152-159 8 p.

研究成果: ジャーナルへの寄稿記事

Flow rate
Screening
Rivers
Wear of materials
4 引用 (Scopus)

Blade rows interaction in contra-rotating axial flow pump designed with different rotational speed concept

Cao, L. L., Watanabe, S., Imanishi, T., Yoshimura, H. & Furukawa, A., 12 1 2013, : : IOP Conference Series: Materials Science and Engineering. 52, TOPIC 2, 022004.

研究成果: ジャーナルへの寄稿Conference article

Axial flow
Turbomachine blades
Rotors
Pumps
Fourier analysis
1 引用 (Scopus)

Effects of tip clearance flow on rotating stall inception process in an axial compressor rotor

Yamada, K., Kikuta, H., Furukawa, M., Gunjishima, S. & Hara, Y., 7 15 2013, : : Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B. 79, 801, p. 900-916 17 p.

研究成果: ジャーナルへの寄稿記事

compressor rotors
rotating stalls
turbocompressors
clearances
Compressors
25 引用 (Scopus)

Effects of tip clearance on the stall inception process in an axial compressor rotor

Yamada, K., Kikuta, H., Furukawa, M., Gunjishima, S. & Hara, Y., 12 17 2013, ASME Turbo Expo 2013: Turbine Technical Conference and Exposition, GT 2013. GT2013-95479. (Proceedings of the ASME Turbo Expo; 巻数 6 C).

研究成果: 著書/レポートタイプへの貢献会議での発言

Compressors
Vortex flow
Rotors
Flow fields
Tornadoes
7 引用 (Scopus)

Experimental analysis of flow structure in contra-rotating axial flow pump designed with different rotational speed concept

Cao, L., Watanabe, S., Imanishi, T., Yoshimura, H. & Furukawa, A., 8 1 2013, : : Journal of Thermal Science. 22, 4, p. 345-351 7 p.

研究成果: ジャーナルへの寄稿記事

axial flow pumps
rotors
flow velocity
pumps
internal flow
12 引用 (Scopus)

Low speed design of rear rotor in contra-rotating axial flow pump

Cao, L., Watanabe, S., Momosaki, S., Imanishi, T. & Furukawa, A., 2 28 2013, : : International Journal of Fluid Machinery and Systems. 6, 2, p. 105-112 8 p.

研究成果: ジャーナルへの寄稿記事

Axial flow
Rotors
Pumps
Vortex flow
Cambers
2 引用 (Scopus)

Suction performance and internal flow of a 2-bladed helical inducer with inlet asymmetric plate

Watanabe, S., Uchinono, Y., Ishizaka, K., Furukawa, A. & Kim, J. H., 10 1 2013, : : Journal of Thermal Science. 22, 5, p. 395-403 9 p.

研究成果: ジャーナルへの寄稿記事

helical inducers
internal flow
suction
cavitation flow
flow measurement
16 引用 (Scopus)

The effect of tip leakage vortex for operating range enhancement of centrifugal compressor

Tomita, I., Ibaraki, S., Furukawa, M. & Yamada, K., 6 28 2013, : : Journal of Turbomachinery. 135, 3, 051020.

研究成果: ジャーナルへの寄稿記事

Centrifugal compressors
Compressors
Vortex flow
Flow rate
Flow structure
1 引用 (Scopus)

Toward direct numerical simulation of aeroacoustic field around airfoil using multi-scale lattice boltzmann method

Kusano, K., Yamada, K. & Furukawa, M., 12 1 2013, ASME 2013 Fluids Engineering Division Summer Meeting, FEDSM 2013. V01AT09A005. (American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FEDSM; 巻数 1 A).

研究成果: 著書/レポートタイプへの貢献会議での発言

Aeroacoustics
Direct numerical simulation
Airfoils
Mach number
Flow fields
2012
6 引用 (Scopus)

An explanation for flow features of spike-type stall inception in an axial compressor rotor

Yamada, K., Kikuta, H., Iwakiri, K. I., Furukawa, M. & Gunjishima, S., 12 1 2012, ASME Turbo Expo 2012: Turbine Technical Conference and Exposition, GT 2012. PARTS A, B, AND C 版 p. 2663-2675 13 p. (Proceedings of the ASME Turbo Expo; 巻数 8, 番号 PARTS A, B, AND C).

研究成果: 著書/レポートタイプへの貢献会議での発言

Compressors
Rotors
Tornadoes
Vortex flow
Flow structure
70 引用 (Scopus)

An Explanation for Flow Features of Spike-Type Stall Inception in an Axial Compressor Rotor

Yamada, K., Kikuta, H., Iwakiri, K. I., Furukawa, M. & Gunjishima, S., 11 5 2012, : : Journal of Turbomachinery. 135, 2, 021023.

研究成果: ジャーナルへの寄稿記事

Compressors
Rotors
Tornadoes
Vortex flow
Flow structure
3 引用 (Scopus)

Development of advanced centrifugal compressor for turbocharger, applying control of internal unsteady flow structure

Ebisu, M., Shiraishi, T., Tomita, I. & Furukawa, M., 1 1 2012, Institution of Mechanical Engineers - 10th International Conference on Turbochargers and Turbocharging. Woodhead Publishing Limited, p. 135-144 10 p.

研究成果: 著書/レポートタイプへの貢献会議での発言

Centrifugal compressors
Flow structure
Unsteady flow
Compressors
Exhaust gases
1 引用 (Scopus)

Experimental study on adjustment of inlet nozzle section to flow rate variation for darrieus-type hydro-turbine

Watanabe, S., Shimokawa, K., Furukawa, A., Okuma, K. & Matsushita, D., 3 1 2012, : : International Journal of Fluid Machinery and Systems. 5, 1, p. 30-37 8 p.

研究成果: ジャーナルへの寄稿記事

Intake systems
Nozzles
Turbines
Flow rate
Inlet flow
25 引用 (Scopus)

Experimental study on simplification of Darrieus-type hydro turbine with inlet nozzle for extra-low head hydropower utilization

Shimokawa, K., Furukawa, A., Okuma, K., Matsushita, D. & Watanabe, S., 5 1 2012, : : Renewable Energy. 41, p. 376-382 7 p.

研究成果: ジャーナルへの寄稿記事

Intake systems
Nozzles
Turbines
Power generation
Torque
5 引用 (Scopus)

On high efficiency operation of contra-rotating axial flow pump with rotational speed control toward effective energy saving

Cao, L. L., Watanabe, S., Imanishi, T., Momosaki, S. & Furukawa, A., 12 1 2012, : : IOP Conference Series: Earth and Environmental Science. 15, PART 4, 042027.

研究成果: ジャーナルへの寄稿Conference article

pump
prediction
speed
energy saving
method
1 引用 (Scopus)

Research on Darrieus-type hydraulic turbine for extra-low head hydropower utilization

Furukawa, A., Watanabe, S. & Okuma, K., 12 1 2012, : : IOP Conference Series: Earth and Environmental Science. 15, PART 1, 012003.

研究成果: ジャーナルへの寄稿Conference article

turbine
hydraulics
cavitation
fluid dynamics
3 引用 (Scopus)

The effect of tip leakage vortex for operating range enhancement of centrifugal compressor

Tomita, I., Ibaraki, S., Furukawa, M. & Yamada, K., 12 1 2012, ASME Turbo Expo 2012: Turbine Technical Conference and Exposition, GT 2012. PARTS A, B, AND C 版 p. 735-743 9 p. (Proceedings of the ASME Turbo Expo; 巻数 8, 番号 PARTS A, B, AND C).

研究成果: 著書/レポートタイプへの貢献会議での発言

Centrifugal compressors
Compressors
Vortex flow
Flow rate
Flow structure
3 引用 (Scopus)

Thermodynamic parameter on cavitation in space inducer

Yoshida, Y., Kikuta, K., Niiyama, K. & Watanabe, S., 12 1 2012, ASME 2012 Fluids Engineering Division Summer Meeting Collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 10th Int. Conference on Nanochannels, Microchannels, and M, FEDSM 2. p. 203-213 11 p. (American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FEDSM; 巻数 2).

研究成果: 著書/レポートタイプへの貢献会議での発言

Cavitation
Thermodynamics
Liquids
Cryogenic liquids
Latent heat
11 引用 (Scopus)

Vibration characteristics due to cavitation in stator element of automotive torque converter at stall condition

Watanabe, S., Otani, R., Kunimoto, S., Hara, Y., Furukawa, A. & Yamaguchi, T., 12 1 2012, ASME 2012 Fluids Engineering Division Summer Meeting Collocated with the ASME 2012 Heat Transfer Summer Conf. and the ASME 2012 10th Int. Conf. on Nanochannels, Microchannels, and M, FEDSM 2012. PARTS A AND B 版 巻 1. p. 535-541 7 p.

研究成果: 著書/レポートタイプへの貢献会議での発言

Torque converters
Cavitation
Stators
Flow separation
Bubbles (in fluids)
2011

Circulation of a vortex ring generated by pulsating jet flow

Akagi, F., Kawabata, K., Ando, Y., Yamaguchi, S. & Furukawa, M., 12 1 2011, ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011. PARTS A, B, C, D 版 p. 2911-2920 10 p. (ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011; 巻数 1, 番号 PARTS A, B, C, D).

研究成果: 著書/レポートタイプへの貢献会議での発言

Vortex flow
Strouhal number
Measurement errors
Momentum
5 引用 (Scopus)

Detached eddy simulation of unsteady flow field and prediction of aerodynamic sound in a half-ducted propeller fan

Kusano, K., Jeong, J. H., Yamada, K. & Furukawa, M., 12 1 2011, ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011. PARTS A, B, C, D 版 p. 713-722 10 p. (ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011; 巻数 1, 番号 PARTS A, B, C, D).

研究成果: 著書/レポートタイプへの貢献会議での発言

Propellers
Unsteady flow
Fans
Flow fields
Aerodynamics
5 引用 (Scopus)

Development of dual-layer PSP/TSP system for pressure and temperature measurements in low-speed flow field

Moon, K. J., Mori, H., Ambe, Y. & Kawabata, H., 12 1 2011, ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011. PARTS A, B, C, D 版 巻 1. p. 2767-2772 6 p.

研究成果: 著書/レポートタイプへの貢献会議での発言

Pressure measurement
Paint
Temperature measurement
Flow fields
Temperature

Effect of leading edge sweep on cavitation performance of two-bladed flat plate inducer

Igoshi, T., Uchinono, Y., Koroitamana, E., Ishizaka, K., Watanabe, S. & Furukawa, A., 12 1 2011, ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011. PARTS A, B, C, D 版 巻 1. p. 289-296 8 p.

研究成果: 著書/レポートタイプへの貢献会議での発言

Cavitation
Flow rate
Surges (fluid)
Flow measurement
Pressure measurement
1 引用 (Scopus)

Experimental stydy on performance of darrieus-type open hydroturbine with inlet nozzle in low downstream water level conditions

Hirowatari, K., Shimokawa, K., Iwamoto, S., Okuma, K., Watanabe, S., Matsusita, D. & Furukawa, A., 12 1 2011, ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011. PARTS A, B, C, D 版 p. 1851-1859 9 p. (ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011; 巻数 1, 番号 PARTS A, B, C, D).

研究成果: 著書/レポートタイプへの貢献会議での発言

Water levels
Nozzles
Turbines
Intake systems
Torque
2 引用 (Scopus)

Formation process of vortex ring generated by a pulsating jet flow

Akagi, F., Okuzono, Y., Ando, Y., Yamaguchi, S. & Furukawa, M., 12 1 2011, : : Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B. 77, 775, p. 546-556 11 p.

研究成果: ジャーナルへの寄稿記事

vortex rings
jet flow
Vortex flow
nozzles
Nozzles
20 引用 (Scopus)

Influence of setting condition on characteristics of Savonius hydraulic turbine with a shield plate

Iio, S., Katayama, Y., Uchiyama, F., Sato, E. & Ikeda, T., 9 1 2011, : : Journal of Thermal Science. 20, 3, p. 224-228 5 p.

研究成果: ジャーナルへの寄稿記事

turbines
hydraulics
clearances
coefficients
upstream

Influence of Setting Condition on Characteristics of Savonius Hydraulic Turbine with a Shield Plate

Iio, S., Katayama, Y., Uchiyama, F., Sato, E. & Ikeda, T., 5 2011, : : Journal of Thermal Science. 20, 3, p. 224-228 5 p.

研究成果: ジャーナルへの寄稿記事

turbines
hydraulics
clearances
coefficients
upstream
8 引用 (Scopus)

The role of tip leakage vortex breakdown in flow fields and aerodynamic characteristics of transonic centrifugal compressor impellers

Yamada, K., Furukawa, M., Fukushima, H., Ibaraki, S. & Tomita, I., 12 1 2011, ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition, GT2011. PARTS A, B, AND C 版 p. 2111-2123 13 p. (Proceedings of the ASME Turbo Expo; 巻数 7, 番号 PARTS A, B, AND C).

研究成果: 著書/レポートタイプへの貢献会議での発言

Impellers
Centrifugal compressors
Flow fields
Aerodynamics
Vortex flow
6 引用 (Scopus)

Unsteady and three-dimensional flow mechanism of spike-type stall inception in an axial flow compressor rotor

Kikuta, H., Iwakiri, K. I., Furukawa, M., Yamada, K., Gunjishima, S. & Okada, G., 12 1 2011, ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011. PARTS A, B, C, D 版 p. 817-829 13 p. (ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011; 巻数 1, 番号 PARTS A, B, C, D).

研究成果: 著書/レポートタイプへの貢献会議での発言

Axial-flow compressors
Vortex flow
Rotors
Flow structure
Tornadoes
2010
11 引用 (Scopus)

Comparative study on tip clearance flow fields in two types of transonic centrifugal compressor impeller with splitter blades

Yamada, K., Tamagawa, Y., Fukushima, H., Furukawa, M., Ibaraki, S. & Iwakiri, K. I., 12 1 2010, ASME Turbo Expo 2010: Power for Land, Sea, and Air, GT 2010. PARTS A, B, AND C 版 p. 2053-2063 11 p. (Proceedings of the ASME Turbo Expo; 巻数 7, 番号 PARTS A, B, AND C).

研究成果: 著書/レポートタイプへの貢献会議での発言

Centrifugal compressors
Turbomachine blades
Compressors
Flow fields
Vortex flow
32 引用 (Scopus)

Development of ducted Darrieus turbine for low head hydropower utilization

Furukawa, A., Watanabe, S., Matsushita, D. & Okuma, K., 3 1 2010, : : Current Applied Physics. 10, 2 SUPPL.

研究成果: ジャーナルへの寄稿記事

turbines
Turbines
exhaustion
cost effectiveness
fossil fuels

Experimental study of cavitating flow in flat plate cascades with/without tip clearance

Watanabe, S., Suefuji, T., Ikeda, A. & Furukawa, A., 2010, 13th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery 2010, ISROMAC-13. p. 1-6 6 p.

研究成果: 著書/レポートタイプへの貢献会議での発言

Unsteady flow
High speed cameras
Video cameras
Cavitation
Vortex flow
1 引用 (Scopus)

Experimental study on leakage flow in labyrinth seals with asymmetric geometries

Nishii, K., Furukawa, A., Watanabe, S. & Miyake, K., 11 25 2010, 10th Asian International Conference on Fluid Machinery, AICFM. 巻 1225. p. 91-99 9 p.

研究成果: 著書/レポートタイプへの貢献会議での発言

labyrinth seals
leakage
convexity
geometry
internal flow