In a propeller design, it is necessary to have a broad criterion of all the factors that can affect the boat, both the spans and dimensions, type of service and type of propeller to be used. To carry out a CFD study, its abbreviation "Computational Fluid Dynamics" is defined after having carried out a propeller selection process and having been properly calculated.

To achieve this, it is necessary to have as much information as possible about the boat, as shown in the following questionnaire.

Link to questionnaire

The CFD process is a branch of fluid mechanics that uses computer numerical procedures to solve flow equations. The CFD methodology is based on subdividing the calculation domain into discrete elements forming a mesh in which the governing differential equations are solved.

At Rice foundries, cases where the propellers have suffered damage due to miscalculation, speed representation, pressure analysis on the blades, etc. are solved.

At Rice foundries, cases where the propellers have suffered damage due to miscalculation, speed representation, pressure analysis on the blades, etc. are solved.

Cavitation problems are very common in marine propellers, which depends, in most cases, on use, care and power. Proper handling of the propeller will preserve its properties and optimum performance.

CASE 1

In the example shown above, a cavitation problem is observed on the thickness face:

Similar to the analysis performed in the fluid software, the water flow caused by the propeller is shown considering the engine revolutions. It also represents an increase in pressure on the propeller faces.

Wear on the tips is observed on the pitch, giving by its own criteria that the propellers have a lack of DAR* which generates cavitation.

^{* DAR blade Diameter Area Ratio.}

CASE 2

In the following representation, a hull and propeller in use were considered, and the reason why the desired speed dropped:

The pressures exerted on the blades are the product of large changes in their magnitudes within a small area, both on the front and rear, which warns of a potential wear of the propeller due to cavitation effects during the start of the propulsion. Some changes in the water velocities on the propeller are observed more noticeably than in the previous simulation, thus concluding that the current propeller had already completed its useful life and a repair was necessary or, failing that, a new propeller.

The image on the left is the current propeller, which reflects cavitation from the use and loss of DAR. In the image on the right is the propeller designed by RICE, with no abnormalities on their faces in contact with water.

The following video shows an example of CFD:

CFD Video

At Rice Foundries we are committed to delivering complete and functional projects, which will bring you benefits in the short and long term, always with the quality that represents us, in attention, quality-price and problem solving.