Drag pumps are rotodynamic machines in which the mechanical energy of a moving a rotor (Dragpeller) is transferred to a fluid through the boundary layer. The fluid enters the pump in the axial direction (parallel to the shaft and perpendicular to the rotor) through the pipe and immediately suction fluid is positioned between the two parallel and rotary plates that form the dragpeller. Once in this position, the fluid particles that are in direct contact with the plates acquire the same velocity as the rotating plates, there is no relative motion between adhering particles and solid surfaces in motion.
The condition of not sliding on the surface generates the maximum value of shear in the fluid and in turn causes the fluid layers to acquire the necessary energy transmitted by the Dragpeller. Once the first layer is energized by molecular diffusion (thanks to fluid viscosity) it transmits its energy to the second layer.
This phenomenon of energy transport is being produced from layer to layer until all of the fluid within the dragpeller is kinetically energized. The fluid aquires kinetic energy from the nearest layer of the surface to the outermost layer (midpoint of interspace). Once all fluid in this space has acquired sufficient kinetic energy it then exits the dragpeller and will address the case where the kinetic energy is converted into pressure energy, directed to the discharge section and then exits the pump.
Dragpumps have a very important quality that differs them greatly from other rotodynamic and centrifugal pumps, the viscosity. Given that the most important physical property in this type of physical pump is the viscosity, these pumps behave hydro-dynamically better when the fluid is viscous. That is to say, if you need to pump a viscous fluid, such as heavy and extra heavy crude, drilling fluids, waxes, bitumen’s, polymer melts, glycerin, oils, lubricants, paper pulp, wastewater, slurries, etc., Dragpumps are the best option.
In addition, other advantages of this technology for the transportation of fluids are the following:
- Handling small and large solids:
- Gas handling:
- Continuous and Pulsating Free Flow:
- Low Radial and Axial Loads:
- Non Emulsifying:
- Low NPSH Levels:
The Dragpeller® is the rotating element in our drag pumps where transformation of mechanical energy into hydraulic energy occurs. It uses the boundary layer principle (Theory developed by Prandtl) and the same physical principle used by Nicola Tesla in "Tesla Turbomachinery" in the early XX century. The principle of operation is the same, however substantial improvements are introduced with our dragpeller like efficient energy conversions and of course, less consumption of mechanical and electrical power.
Basically, it is geometrically formed by two parallel circular plates that cut on the same axis and are connected rigidly by elements called blade posts. Each one of the plates has a number of elements attached that help generate an apparent rough surface and therefore, according to rheological model fluid pumping generate more shear and increase the transport amount of movement. These elements are called "High efficiency dragpeller vanes" (HEDV). The geometry of these elements, in terms of drag factor, centrifugal effect and aerodynamic tail ensure much higher energy efficiency than other impeller pumps with similar technologies. For such applications, our Dragpumps have efficiencies up to 15% greater than the efficiencies of pumps with similar technologies. In other words, if we operate a Dragpump that consumes 500 HP of power, in the same application, our competitors pump energy consumption would be approximately 575 HP, that is 75 HP more, which equals 56 KW. Annually, our dragpeller saves approximately 90,560 KW-hr.