At its location in the UAE, Dredge Yard engineers develops and supplies dredging and mining equipment such as dredge pumps, ball joints, cutter heads and complete dredgers. The dredge pump is a dredger's main component and is critical to achieving production. Dredge pumps also consume the most power during operation, so efforts to reduce the pump's power needs through smarter design are critical. Dredge pumps involve more complex engineering challenges than water pumps. They must carry water filled with a diverse, dense mixture of solids, including mud, fine sand, coarse sand, gravel, stones and other debris. The pumped water does not behave like a homogenous fluid because of the different viscosities. The soil tends to settle down and slide on the pipe bed, depending on the flow speed. Another challenge is that pump parts wear quickly. Clogged impellers and breaking vanes also pose risks to pump performance. Equipment replacement can eat away at operational efficiency and increase the dredger's overall lifetime costs.
As the demand for larger dredgers rises, engineers turn to computational fluid dynamics for accurate tests before delivering site prototypes.
07/20/2015
Figure 1. Large dredge pumps (above) often rely CFD software (below) for an efficient hydraulic design. (Graphics courtesy of Dredge Yard and Simerics)
Figure 2. CFD programs simulate flow through dredge and other wastewater pumps in order to produce a 3-D model.
Figure 3. The 3-D models take into account such performance measurements as flow rate, head and cavitation for many of the pump's components.
Demand has recently grown in the market for even bigger dredgers. Dredge pump size must increase from 1,400 to 1,600 mm—even 1,800 mm. Larger suction pipes and dredge pumps must be designed to fill the dredgers in less than two hours.
New design methods are needed to efficiently adapt to the new market demand. Pumps must be tested and analyzed for efficiency and performance. Foundries with casting capacity of 50 tons and heavy-steel machinery 6 meters in diameter are required when casting and machining the pump cases.