Views:4556 Author:Site Editor Publish Time: 2016-01-16 Origin:Site
Normal Marine Tunnel Thruster Propeller: simple structure, under the low efficiency of average or higher.
General propeller propulsion energy loss:
(1) produce axial induced velocity loss.In propeller as thrusters to work, this is not completely avoid the loss, but can use appropriate measures to reduce the loss as much as possible.Generally, this kind of loss value will vary depending on the propeller load coefficient increases.
(2) weeks to the induced velocity loss, or called reverse current loss, the loss value will also increases with the propeller load coefficient.
(3) the blade during operation and the water loss as a result of the viscous friction role, or section resistance loss.Propeller induced resistance loss and profile loss both about 35% ~ 60% of the total consumption of propeller power, that is to say, the propeller general power to be obtained from the host to exit the press power accounts for only about 40% ~ 40%.Interaction,
(4) air propeller and propeller appendage resistance loss.
Measures for decreasing the energy loss:
(1) as to reduce the loss of induction, can use a bigger diameter propeller, but can increase the profile of resistance loss.
(2) the reverse in order to reduce water loss, can use special training equipment, such as: reaction rudder and rudder thrust fin and flow linear rudder, reduce the wake rotation, recycling drafting energy, achieve the goal of improve the propulsive efficiency.Section
(3) in order to reduce resistance losses, must pay attention to the choice of blade section shape, in theory, in the design of reasonable selection of blade width, thickness ratio and section shape, can make the profile of resistance loss minimum
(4) the propeller and hull and possessed reasonable match, can not only decrease the thrust deduction scores and can more effective use of wake, and also can improve the efficiency of the propeller itself.