Efficiency thermoelectrics utilizing convective heat flow

#1. Field of the Invention

#The present invention relates to improved thermoelectrics for producing heat and/or cold conditions with greater efficiency.

#2. Description of the Related Art

#FIGS. 1A and 1B depict a conventional thermoelectric device;

#FIG. 2 depicts a conventional thermoelectric device in a conventional fluid heating or cooling application;

#FIG. 3 depicts a conventional thermoelectric element for use in cooling a material or component;

#The invention is introduced using examples and particular embodiments for descriptive purposes. A variety of examples are presented to illustrate how various configurations can be employed to achieve the desired improvements. In accordance with the present invention, the particular embodiments are only illustrative and not intended in any way to restrict the inventions presented. In addition, it should be understood that the terms cooling side, heating side, cold side, hot side, cooler side and hotter side and the like do not indicate any particular temperature, but are relative terms. For example, the “hot,” “heating” or “hotter” side of a thermoelectric element or array may be at ambient temperature, with the “cold,” “cooling” or “cooler” side at a cooler temperature than ambient. Conversely, the “cold,” “cooling” or “cooler” side may be at ambient with the “hot,” “heating” or “hotter” side at a higher temperature than ambient. Thus, the terms are relative to each other to indicate that one side of the thermolectric is at a higher or lower temperature than the counter-designated side. Similarly, the terms “cooling side” and “heating side” are not intended to designate the particular use for a thermoelectric system in any given application.

#A block diagram of an overall TE system 600 is shown in FIG. 6. A thermoelectric assembly 601 with hot side 603 and cool side 604 is electrically connected to a power source 602. The thermoelectric assembly 601 is in good thermal contact with a hot side heat exchanger 607 on the hot side 603 and with a cool side heat exchanger 608 on the cool side 604. Equipped with suitable ducts or pipes, sources of fluid, 605 for the hot side 603 and 606 for the cool side 604, send their fluids through their respective heat exchangers 607 and 608. Heated fluid 609 and cooled fluid 610 exit the system at the right in FIG. 6. For certain applications (with examples given below) one of the heat exchangers 607 or 608 may be replaced with a heat sink, thereby eliminating the need for a fluid source or fluid on that side.

#The present invention is based on the concept that the conductive/loss heat transport terms in Equations 1 and 3 which contain K and R, can be modified by the use of steady state convection through the array so as to diminish their overall effect on system performance. How this can be accomplished can be understood by first looking at the equations that govern heat generation and flow in a conventional TE. For simplicity, assume that material properties do not change with current and temperature, heat and current flow are one-dimensional, and that conditions do not vary with time. For this case: - K ⁢ ⁢ ⅆ 2 ⁢ T ⅆ x 2 ⁢ = I 2 ⁢ R L ( 18 )