High efficiency fluid movers

Abstract

Fluid movers produce at least predominantly laminar flow internally in an axial or a radial direction in a rotor. A fluid mover rotor comprises a matrix of passages of appropriate size to produce at least predominantly laminar flow spaced circumferentially around the rotor. The passages may provide axial, radial or mixed flow. “Appropriate” dimensions may be selected for a specified volume flow rate. In a radial embodiment, a matrix of radially extending passages could comprise walls having an axial height projecting from an annular disk. The passages may be offset with respect to the radial direction to provide an angle of attack that minimizes incidence losses. The matrix structure allows the use of thin-walled passages to minimize blockage of entering air.

1 . A rotor to transfer momentum with a fluid when operating at a pre-selected volumetric flow rate through the rotor, said rotor comprising a plurality of passages formed in said rotor for transferring momentum into or out of the fluid as said fluid passes through said passages in response to rotation of said rotor, wherein said passages are formed with a cross sectional shape and cross sectional dimensions along their entire length sufficient to establish and maintain laminar flow of said fluid along the entire length of said passages when said fluid is passing through said rotor at said pre-selected volumetric flow rate.  
   
   
       2 . A rotor according to  claim 1 , wherein said passages comprise a plurality of substantially parallel passages.  
   
   
       3 . A rotor according to  claim 1 , wherein most or all of said passages are completely enclosed.  
   
   
       4 . A rotor according to  claim 1 , wherein said rotor comprises an annular form receiving fluid input at an inner diameter thereof and wherein said passages provide a path in a radial direction from said inner diameter to an outer diameter of said rotor.  
   
   
       5 . A rotor according to  claim 1 , wherein said rotor defines a substantially cylindrical envelope receiving fluid input at a first major surface thereof and wherein said passages provide a path in an axial direction from said first major surface to a second major surface of said rotor.  
   
   
       6 . A rotor according to  claim 1 , wherein said passages are equiangularly spaced and wherein said rotor comprises a plurality of adjacent sets of passages.  
   
   
       7 . A rotor according to  claim 6 , wherein said rotor comprises a central hub and an outer member wrapped around said hub and comprising said passages.  
   
   
       8 . A rotor according to  claim 1 , wherein said rotor comprises a porous solid.  
   
   
       9 . A rotor according to  claim 8  wherein said rotor comprises reticulated foam.  
   
   
       10 . A rotor according to  claim 8  wherein said rotor comprises screen mesh wound in layers.  
   
   
       11 . A porous rotor according to  claim 8 , in which the open volume of the porous solid is above 50%.  
   
   
       12 . A fluid-moving turbomachine comprising the rotor according to  claim 1  and a concentrically mounted stator assembly, wherein said stator assembly is formed with dimensions to establish and maintain laminar flow of said fluid along the entire length of said passages when said rotor is operating at said pre-selected volumetric flow rate.  
   
   
       13 . A rotor according to  claim 1 , wherein said passages have a surface roughness of greater than 1.6 microns.  
   
   
       14 . A rotor according to  claim 1  having passages formed by walls having a range in thickness of as low as 25% of a nominal thickness to as high as 300% of a nominal thickness.  
   
   
       15 . A rotor according to  claim 1 , wherein selected passages subtend unequal angles about said inner diameter.  
   
   
       16 . A rotor according to  claim 1 , wherein said rotor comprises a plurality of layers.  
   
   
       17 . A rotor according to  claim 16 , wherein each layer comprises a prime number of passages.  
   
   
       18 . A rotor according to  claim 17 , wherein passages in one layer are angularly displaced with respect to the passages in an adjacent layer.  
   
   
       19 . A rotor according to  claim 16 , wherein a number of passages in one layer is not factorable by a same group of numbers by which at least one other layer is factorable.  
   
   
       20 . A rotor according to  claim 16 , wherein at least two different layers have different passage geometry.  
   
   
       21 . A rotor according to  claim 1 , having a diameter of 1 mm to 100 mm.  
   
   
       22 . A rotor according to  claim 1 , wherein said passages each have a ratio of maximum cross sectional dimension to minimum cross sectional dimension of about 1.0 to about 3.0.  
   
   
       23 . A rotor according to  claim 22 , wherein said passages each have a ratio of maximum cross sectional dimension to minimum cross sectional dimension of about 1.0 to 1.5.  
   
   
       24 . A rotor according to  claim 1 , wherein said passages have flow lengths less than the length required for a fully developed laminar flow velocity profile.  
   
   
       25 . A rotor according to  claim 24  wherein said passages have flow lengths less than 20% of the length required for a fully developed laminar flow velocity profile.  
   
   
       26 . A rotor according to  claim 1 , wherein said rotor has an open area of at least 70% at an air inlet surface.  
   
   
       27 . A rotor according to  claim 1 , wherein passage dimensions are selected to provide passage flow areas that result in flow characterized by a Reynolds Number in the range of 200 to 2300 at a preselected flow rate.  
   
   
       28 . A rotor according to  claim 27 , wherein passage dimensions are selected to provide passage flow areas that result in flow characterized by a Reynolds Number in the range of 1000 to 2000 at a preselected flow rate.  
   
   
       29 . A rotor according to  claim 1  wherein said passages have cross sections which pack.  
   
   
       30 - 33 . (canceled)  
   
   
       34 . A fluid mover comprising: 
 a rotor coupled to a motor for rotational motion around an axis;    passages extending through said rotor, wherein substantially all of said passages have a characteristic cross sectional dimension at all points along their length defined by      200( Aν/Q )< D< 2300( Aν/Q ),    where ν is the kinematic viscosity of the fluid moved by the rotor, Q is a volumetric flow rate of the fluid moved by the rotor, and A is the smaller of an open air inlet or open air outlet area.    
   
   
       35 . The fluid mover of  claim 34 , wherein said rotor has a diameter of less than or equal to about 100 mm, and wherein said rotor defines a fluid inlet area A 1  and a fluid outlet area A 2 , wherein A 1  and A 2  are both equal to or less than about 5000 mm 2 .  
   
   
       36 . The fluid mover of  claim 34 , wherein said characteristic cross sectional dimension is the hydraulic diameter.  
   
   
       37 . The fluid mover of  claim 34 , wherein substantially all of said passages have a maximum cross sectional dimension that is 2D h  or less.  
   
   
       38 . The fluid mover of  claim 34 , wherein said passages are substantially rectangular in cross section with sides of length a and b, and wherein said characteristic cross sectional dimension is 2ab/(a+b).  
   
   
       39 . The fluid mover of  claim 34 , wherein a cross sectional shape of said passages is selected from triangular, rectangular, and hexagonal.  
   
   
       40 . The fluid mover of  claim 34 , wherein said fluid mover has a peak efficiency of greater than about 10%.  
   
   
       41 . The fluid mover of  claim 34 , wherein said passages are formed from walls having a surface roughness of greater than 1.6 microns.  
   
   
       42 . A method of cooling one or more electronic circuits, said method comprising: 
 forcing air to flow through a plurality of passages such that the flow is characterized by a Reynolds number through said passages of between 200 and 2300; and    directing said air toward said electronic circuits and/or toward heat dissipating components thermally coupled to said electronic circuits.    
   
   
       43 . The method according to  claim 42 , wherein most or all of said passages are completely enclosed.  
   
   
       44 - 68 . (canceled)