Design and Development of Duct-Diffuser Augmented Propeller Low Head Hydro Turbines

Tauseef Ahmed – ta3e09@soton.ac.uk - Faculty of Engineering and the EnvironmentFaculty of Engineering and the EnvironmentUniversity of Southampton

Supervisors – Dr Stephen Turnock , Dr Richard Wills, Dr Syed Waheed (NUST)

Fluid Structure Interactions Research Group

Introduction

On economic grounds, the criteria for design and development of Low Head Hydro

(LHH) turbines are based on minimum cost per unit power instead of maximum delivered

power. The drawback of this approach often results in undue design simplification, and

hence possibly unfeasible predictions of the likely hydraulic power potential along with

below average performance of the design models.

Governmental and global targets for reduction in carbon emissions, environmental

impacts and the capability of serving the ever increasing demand of power requirements in

the shortest time are driving forces for small/low head hydro power generation.

Design Criteria

The adopted methodology for maximum deliverable power criteria follow integration of

meaningful geometry for generalized design instead of site specific tuning of non-hydro

dynamic components. The addition of hydrodynamic flow regulating components for

power augmentation and system level modification of component for extended range of

application of technology are the main features of proposed criteria.

Design and development status of proposed LHH

Based on the design to manufacture approach and above mentioned criteria of maximizing

energy for extended range of application two LHH configurations namely Diffuser

Augmented and Duct-multilevel Diffuser Augmented turbine are proposed.

Following diagrams highlights schematic and component diagrams

CFD modelling and Analysis of proposed LHH turbine models

Objectives of the project

This research aims to support more consistent and optimised design

with enhanced systems performance for low/ultra- low head hydro-

electrical power generations. This project under International

Strategic Participation In Research and Education (INSPIRE)

initiative of British Council has the following goals

To exploit the potential of LHH for power output range 0.2Kw to

25kw

Flexible design for a range of operating conditions at system and

component level

Continuous operation at full capacity for maximum duration with

minimum control regulations (on grid/off grid)

To develop new design concept of low/small scale hydro power

generation

Hydro dynamically efficient turbine runner

Performance data acquisition of laboratory units for optimum

design of site specific units

Understand fully the design for propeller turbines using CFD

modelling, and laboratory experimentsAcknowledgement

This research is jointly sponsored by National University of Sciences and Technology (NUST) and British Council International Strategic Partnership In Research & Education (INSPIRE) Initiative

References [1] International Journal of Hydropower and Dams: World Atlas. Sutton: Aquamedia Publications, 2000.

National University of National University of Sciences and Technology Sciences and Technology (NUST)(NUST)

The modern design, analysis and manufacturing techniques can contribute to investigate

hydro potential as low as 1 meter head and a power output of 200 Watts

CAD/CAM based automated design and analysis process for LHH applications is opted

for real cost effective LHH designs.

To simulate internal flow within turbine passages for accurate prediction of flow physics,

3 D Navier Stroke equations are solved using commercial software ANSYS CFX. The

associated ANSYS ICEMCFD package for grid generation is used along with

SolidWorks for CAD modelling.

Figure 5 Diffuser Augmented complete CAD model assembly

Fig.8 Stream line plot of velocity distribution through the model turbine unit

Fig 9 Velocity distribution in stationary frame for modified geometry

Fig.7 Rotor-Stator Interface modelling

Application of Computational fluid dynamic

techniques particular to LHH turbine

operational range of parameters to evaluate

Complex 3-D flow visualization

Component behaviour characterisation

Design optimization

Small-scale hydro power is the key source

for further hydro development.

Optimization of existing recourses for

power harnessing has made application of

low head hydro power a choice for water

treatment plants, water and waste water

networks

TWh/Year

Figure 1 Global Hydro resources review in terms of power production [1]

runner

Diffuser

Figure 6 Duct-Diffuser Augmented complete CAD model assembly

Fig 2 Stator CAD model Fig 3 3D Runner CAD model

Fig 4 Runner and 7 degree diffuser CAD assembly