Plant And Hydraulic Investigations

SMEC possesses a highly developed capability and extensive experience in the specialist area of investigation of hydraulic systems of hydro power plant, pumping plant and gravity feed hydraulic systems. This capability extends to site investigations, site experimentation and testing, in addition to desk-top computer simulation.

Such specialist investigations and activities include:

• hydraulic surge analysis of hydraulic waterways
• hydraulic pressure transient analysis of hydraulic waterway
• performance testing of pumps and turbines
• optimisation of turbine dewatering systems
• optimisation of air admission systems for rough running turbines.

SMEC’s capability in the area of plant and hydraulic investigations has been established and refined through years of research and development in direct association with water, irrigation and hydro utilities around the world.

The capability includes the application of the latest sophisticated computerised tools and methods to model the hydraulic phenomena under consideration, and to optimise and detail design measures to control, overcome, avoid or mitigate the potentially catastrophic consequences of the mismanagement of moving columns of water.

SCOPE OF SERVICES

• Surge analysis and surge tank stability
• Hydraulic pressure transients
• Performance review and testing of hydraulic plant

SMEC's capability in the area of hydro power plant and hydraulic investigations has received global acclaim during the planning and implementation of the Snowy Mountains Hydroelectric Scheme, which effected the diversion of the major east flowing rivers to the western slopes of the Great Dividing Range. Since then, the capability has been refined and regularly updated in accordance with world best practice.

The plant and hydraulic investigation services currently offered by SMEC are extensive and include:

Surge analysis and surge tank stability

• modelling of water surge characteristics in the hydraulic waterways of hydro-power, pumping and gravity systems during extreme events. Typically, the extreme events include full load acceptance at the maximum rate the plant will permit, full load rejection due to power failure or plant fault, and various combinations of such events.

• where upper and lower surge tanks are employed, the identification of minimum surge tank dimensions to achieve steady state stability.

Hydraulic pressure transients

• SMEC has the capability to perform computer modelling of hydraulic pressure transients in pumping, hydro-power and gravity feed systems. Generally, the extreme events have the most impact on the system performance and design. These include rapid load rejection, failure of pump shaft input power, failure of the ability to export power, rapid load acceptance and sudden opening or closure of valves. SMEC also has the capacity to identify and analyse hydraulic resonant conditions which may develop in hydraulic waterways.

• the tools SMEC employs for the computer analysis also model pumps or turbines inertia, governor characteristics and speed transients. The software utilised includes a combination of inhouse and proprietary software including :

  • MSTA - dynamic surge tank analysis software

  • MGMS - dynamic pressure transient software for pumping and hydropower plant.

  • MRES - analysis of hydraulic systems subject to resonant conditions

  • MIKE 11 - branching networks subject to pressure and channel flows

  • WATSYS - steady state network flows

   

• identification of appropriate pressure control strategies or devices to limit the magnitude of the transient event. Strategies typically employed include the slowing of the guide vane operating rates and valve operating times, employing bypass check valves, surge tanks, air chambers, and water passage sizing.

• determination of the appropriate design parameters to cater for the extreme pressure conditions generated within water passages under transient conditions.