Introduction of RIAM-COMPACT Takanori UCHIDA takanori@riam.kyushu-u.ac.jp Research Institute for Applied Mechanics (RIAM) Kyushu University 6-1 Kasuga-koen, Kasuga-city, Fukuoka 816-8580, JAPAN (RIAM-COMPACT CO., LTD. )
Classification of Fluid Dynamics Computational Fluid Dynamics (CFD) Technique to investigate fluid motions with computers Experimental Fluid Dynamics Technique to investigate fluid motions with velocity and pressure measurements in indoor experiments (e.g., wind tunnel and water tank experiments) Theoretical Fluid Dynamics Technique to investigate fluid motions with mathematical and analytical approaches Sketch of vortices by Leonardo da Vinci http://weather.is.kochi-u.ac.jp/ Karman vortices formed downstream of Jeju Island, South Korea
CFD as an Alternative Tool to Wind Tunnel Experiments Wind tunnel experiments require: high cost including cost of model construction a large amount of time Urban area Numerical simulations (CFD) to supplement wind tunnel experiments Numerical simulations (CFD) to lead wind tunnel experiments Numerical simulations (CFD) to replace wind tunnel experiments http://www.takenaka.co.jp/ Natural terrain Experiments with numerical simulations (CFD) (numerical experiments) Wind engineering field: CWE (Computational Wind Engineering) CFD technique (software) Computer (hardware) Rapid progress Appearance of wind tunnel experiments
Micro-siting 1 Wind power generation: wind power is a reusable natural energy source (wind power electricity) and has attracted significant attention recently! Wind energy is proportional to the swept area, A, and the cube of the wind velocity. When wind velocity is doubled Wind power output is multiplied by 8! Ideal to construct a wind turbine at a location with optimum wind conditions! Rotor diameter D Swept area A Search for wind turbine construction sites Micro-siting technique
Micro-siting Micro-siting 2 Final selection of wind turbine construction sites Mechanical factors are the major consideration Need to take topographical effects on wind into consideration (wind change and disturbance) Use of RIAM-COMPACT Vortex shedding, COMPACT flow detachment, (CFD flow reattachment, and reverse flow technique)
Comparison of RIAM-COMPACT COMPACT and WAsP RIAM-COMPACT WAsP
Non-stationary and non-linear wind synopsis simulator RIAM-COMPACT software The field that utilizes RIAM- COMPACT most frequently: Wind power generation field Main features Non-stationary and non-linear CFD model Adopted an LES turbulence model that is considered more promising than a RANS turbulence model Applicable for all flat and complex topographies of the world by linking to GIS Wind velocity and turbulence intensity distributions can be viewed in 3-D animations Annual power output and utilized capacity can be evaluated based on observation data Velocity vector field at hub height (64m) Generates time series of wind data for evaluating wind load on wind turbines Displays distributions of wind velocity and vertical profiles of wind velocity at wind turbine sites Outputs blow up and blow down angles within the swept area of the wind turbine
Structure of RIAM-COMPACT COMPACT Software for Natural Terrain Pre-processing Grid generation (RC-Elevgen) Step for inserting turbines (RC-WindmillMaker) Addition of surface roughness (RC-RoughnessMaker) Solver Solver (RC-Solver ) Including go.exe Postprocessing Visualization of fluid motions (RC-Scope) Evaluation of annual power output (RC-Explorer)
RIAM-COMPACT Past Research Results: Verification with Wind Tunnel Experiments
Type: single circuit, suction type Test section dimension: 13.5m (L) x 1.5m (W) x 1.2m (H) Wind velocity: 0.1~2 [m/s], set to 1.5 [m/s] for present study Reynolds number: Re(=UD/ν)=10,000 Thermally Stratified Wind Tunnel
View of the Experiment
Computational Results of RIAM-COMPACT: Visualization of Flow Field near a 2-D 2 D Mountain Flow Instantaneous field, vorticity distribution (ω y =±12), streamwise cross-section at the center of the span (y=0) Time-averaged field (Δt=100),streamline graph, averaged in spanwise direction, reattachment length: approx. 7 h
Comparison between Experimental Results and Numerical Computations Measurement points (central cross section) A 点 B 点 C 点 D 点 E 点 F 点 G 点 I 点 10 :RIAM-COMPACT (numerical computation) :Wind tunnel experiment Mean wind velocity profiles in streamwise (x) direction 10 10 10 8 8 8 8 6 z*/h 6 z*/h 6 z*/h 6 z*/h 4 4 4 4 2 2 2 2 0 0 0 0-0.5 0 0.5 1 1.5-0.5 0 0.5 1 1.5-0.5 0 0.5 1 1.5-0.5 0 0.5 1 1.5 <u>/u <u>/u <u>/u <u>/u ref ref ref ref Point E Point F Point G Point I *Normalized by upper-air wind velocity, U ref, for all measurement points in both the numerical computation and the wind tunnel experiment.
Application Examples of RIAM-COMPACT : Wind Power Generation
Example of RIAM-COMPACT Wind Farms of Palm Springs, California Velocity Vectos at Hub Height
Example of RIAM-COMPACT Wind Farms of Palm Springs, California Velocity Vectos at Hub Height
Example of RIAM-COMPACT Wind Farms of Palm Springs, California Velocity Vectos at Hub Height
Example of RIAM-COMPACT Wind Farms of Palm Springs, California Velocity Vectos at Hub Height
Reproducibility of Actual Wind Velocities Cape Noma Wind Park, Kagoshima Prefecture, Japan
Calculation Result 1 25 風速 (m/s) 20 No.1 No.4 観測値 予測値 15 10 Wind speed from anemometer installed on nacelle 5 0 2003 年 1 月 2 日 2003 年 1 月 3 日 2003 年 1 月 4 日 Temporal change of wind speed at the hub height of Wind Turbine #1, Jan. 2 Jan. 3, 2003 (for 2 days), 1-minute values, 2880 data points
Calculation Result 2 Error relative to the observed values of monthly average wind speed: less than 10% Error relative to the No.1 No.4 observed values of annual average wind Monthly average wind speed at the hub height of Wind Turbine speed: #1, less June 2002 May 2003 (one year) than 1%
Introduction of Unsteady and Non-Linear Wind Synopsis Simulator, RIAM-COMPACT COMPACT Example of Micro-siting Wind speed(m/s) 25 Takanori UCHIDA and Yuji OHYA Research Institute for Applied Mechanics (RIAM), Kyushu University 20 15 10 5 Observation Prediction OBJECTIVE Concentrating on a space of several km or less, we are developing an unsteady, non-linear-type numerical simulator called the RIAM-COMPACT (Research Institute for Applied Mechanics, Kyushu University, COMputational Prediction of Airflow over Complex Terrain). The RIAM-COMPACT adopts an LES (Large-Eddy Simulation) technique as a turbulence model. FEATURE Calculation time for 1 simulation:15 minutes (Windows OS PC,51 51 31mesh) Possible to calculate annual energy output (see figure below) Developed and Sold by RIAM-COMPACT Co., Ltd. (Established 2nd Oct 2006) Annual Energy Output 0 2003/1/2 2003/1/3 2003/1/4 The relative error to the observation value of an annual average wind speed was within 10%. Example of Wind Diagnosis of Wind Farm Flow 5m resolution WTGs 50m resolution Inappropriate point Appropriate point Turbulence is generated. (Vortex shedding) REFERENCE T.Uchida and Y.Ohya, Micro-siting Technique for Wind Turbine Generator by Using High Resolution Elevation Data,JSME International Journal, Environmental Flows, Series B, Vol.49, No.3, pp.567-575, 2006. T.Uchida, Y.Ohya, Micro-siting Technique for Wind Turbine Generator by Using Large-Eddy Simulation, Journal of Wind Engineering and Industrial Aerodynamics, in Press (2008) CONTACT US About RIAM-COMPACT : takanori@riam.kyushu-u.ac.jp About Soft sales : contact@riam-compact.com http://www.riam-compact.com/ (in Japanese)
Introduction of Unsteady and Non-Linear Wind Synopsis Simulator, RIAM-COMPACT COMPACT Takanori UCHIDA and Yuji OHYA Research Institute for Applied Mechanics (RIAM), Kyushu University, JAPAN OBJECTIVE Concentrating on a space of several km or less, we are developing an unsteady, non-lineartype numerical simulator called the RIAM-COMPACT (Research Institute for Applied Mechanics, Kyushu University, COMputational Prediction of Airflow over Complex Terrain). RIAM-COMPACT adopts an LES (Large-Eddy Simulation) technique as a turbulence model. Wind characteristics over complex terrain (terrain-induced turbulence) are one of the major issues to be considered for the installation of wind power generation facilities. Main Features Key factors are Animation Display and Rigorous Project Evaluation Non-Stationary and Non-Linear CFD Model Adopted an LES turbulence model that is considered more promising than a RANS turbulence model Applicable for all flat and complex topographies of the world by linking to GIS technique Wind velocity and turbulence intensity distributions can be viewed in 3D animations Annual power output and utilized capacity can be evaluated based on observation data Generates time series of wind data for evaluating wind load on wind turbines Displays distributions of wind velocity and vertical profiles of wind velocity at wind turbine sites Outputs blow up and blow down angles within the swept area of the wind turbine Example of Micro-siting Examples of RIAM-COMPACT COMPACT Natural Terrain Version Software Sales Eurus Energy Holdings Corporation Electric Power Development Co.,LTD / J-POWER Japan Wind Development Co., Ltd. / JWD Numerous wind power generation companies, national research institutes, and universities in Japan and abroad Numerous cases of consulting service for sites in Japan and abroad, utilizing the RIAM-COMPACT software Example of Wind Diagnosis of Actual Wind Farm Flow 5m resolution WTGs 50m resolution Inappropriate point Appropriate point REFERENCE (1) T.Uchida and Y.Ohya, Micro-siting Technique for Wind Turbine Generators by Using Large-Eddy Simulation, Journal of Wind Engineering & Industrial Aerodynamics,Vol.96, pp.2121-2138, 2008 (2) T.Uchida and Y.Ohya, Verification of the Prediction Accuracy of Annual Energy Output at Noma Wind Park by the Non-Stationary and Non-Linear Wind Synopsis Simulator, RIAM- COMPACT, Journal of Fluid Science and Technology, Vol.3, No.3, pp.344-358, 2008 (3) T.Uchida and Y.Ohya, Application of LES Technique to Diagnosis of Wind Farm by Using High Resolution Elevation Data, JSME International Journal Environmental Flows, Series B, Vol.49, No.3, pp.567-575,2006 Turbulence is generated. (Vortex shedding) Inappropriate point Appropriate point Wind speed(m/s) 25 20 Observation Prediction 15 10 5 0 2003/1/2 2003/1/3 2003/1/4 The relative error to the observation value of an annual average wind speed was within 10%. CONTACT US About RIAM-COMPACT : takanori@riam.kyushu-u.ac.jp About Soft sales : contact@riam-compact.com (http://www.riam-compact.com/) REMARKS RIAM-COMPACT Natural Terrain Version software development is mainly performed by RIAM-COMPACT Co., Ltd. with cooperative efforts from Environmental GIS Laboratory Co., Ltd., West Japan Engineering Consultants, Inc., and FS Consulting Co., Ltd. The technical core of the software was principally developed by Dr.Takanori Uchida of the Research Institute for Applied Mechanics, Kyushu University, Japan. An exclusive license of the pertinent components has been granted to RIAM-COMPACT Co., Ltd. by Kyushu TLO Co., Ltd.