Heat exchanger and temperature control unit
AssigneeAdvanced Thermal Sciences Corp.
InventorsKenneth W. Cowans, William W. Cowans, Glenn W. Zubillaga
Life of this patent
Estimating the term…
Abstract
Systems and methods for heat exchange in accordance with the invention define adequately long-interchange distances for two fluids by wrapping a tube containing a first fluid about the wall of an inner cylindrical tank, within a gap formed with a second concentric tank. A second fluid is transmitted in the space defined between the turns of the tube and the two walls, providing effective short length thermal interchange through the tube walls. The tube is in the line contact with both tank walls and the fluids can flow rapidly over an adequately long length, so that high efficiency is provided in a low cost system.
Claims16
A compact, low cost heat exchanger comprising:
- a double walled cylindrical element for receiving a thermal transfer fluid and including an internal cylindrical chamber and a gap between the walls;
- a pump for the thermal transfer fluid including a pumping element immersed in the internal cylindrical chamber;
- a fluid transfer system supplying thermal transfer fluid into the gap between the cylindrical walls;
- and
- a tubular system for transporting a temperature regulating fluid comprising a hollow tubular body helically wrapped with a selected spacing between turns of the helix about the inner wall in the gap between the walls of the double walled cylindrical element, and the tubular body contacting both walls of the cylindrical element for circulating the temperature regulating fluid about the periphery of the cylindrical element in heat exchange relation to thermal transfer fluid flowing in the gap within the spacing between turns of the helix.
A heat exchanger for heating or cooling and thermal transfer fluid with a refrigerant comprising:
- a double walled tank having a central axis, for internally holding a thermal transfer fluid, there being a gap between the walls, the tank including an interior volume within the tank that is in communication with the gap, and containing thermal transfer fluid, there being at least one aperture between the gap and the interior volume;
- a helical tubing disposed in the gap between the walls of the tanks and extending about the central axis, and physically contacting both walls to provide a helical flow path for thermal transfer fluid between the turns of the helical tubing along the direction of the central axis, and;
- a thermal energy fluid source coupled to provide refrigerant flow within and through the helical tubing in thermal exchange with the thermal transfer fluid, wherein the exchanger provides constantly moving refrigerant and fluid in adjacent flow paths, and wherein the inner wall of the double walled tank includes a helical exterior ridge at a selected pitch, and the helical tubing is tensioned on the inner tank against the ridge in line contact.
A system for controlling the temperature of a thermal transfer fluid for use in a process tool comprising the combination of:
- a compressor for receiving a refrigerant and providing a pressurized refrigerant of high enthalpy;
- a condenser system for converting the refrigerant from the compressor to a pressurized refrigerant at substantially ambient temperature with a principal path;
- a conduit system providing a high pressure gaseous refrigerant from the compressor in a bypass path;
- a solenoid expansion valve system for providing controlled hot gas flow from the bypass path;
- a thermal expansion valve for providing an expanded refrigerant at a selected temperature level from the condenser output on the principal path;
- a volumetric heat exchanger having helically disposed, interspersed fluid flow paths for refrigerant and thermal transfer fluid and coupled to receive fluid from the bypass path and the condenser fluid path;
- and
- a controller system including controls for the flow in the bypass path and the principal path, for governing the temperature and enthalpy of the refrigerant.
The method of assembling a heat exchanger having a hollow tubing wrapped helically within a circumferential gap between the walls of a double walled cylindrical tank about a central axis with the inner tank having a helical ridge of a selected pitch on the outer wall thereof, the tubing being disposed such that a fluid can be directed between the turns of the tubing without cross transfer of the fluid between adjacent turns comprising the temps of:
- providing a helical tubular coil which when relaxed has a helical diameter greater than the inner wall component of the tank;
- placing the relaxed tubular coil in approximate position over the outer wall of the inner tank component;
- aligning the upper turn of the helical coil circumferentially and longitudinally on the inner tank component;
- stretching the tubular coil along the central axis to reduce the helical diameter until the coil inner surface contacts the ridges on the outer wall of the inner tank;
- inserting the inner tank component and helical tubular coil thereon within the outer tank component;
- and
- engaging the outer surface of the coil in sealing line contact with the inner surface of the outer tank component.
The method of assembling a heat exchanger in which cylindrical tank components are to be assembled with a predetermined radial gap between two cylindrical tank components when nested together about a central axis, one fluid in the thermal energy exchange to be flowed helically within a helical tubing in the gap and the other fluid to flow in the interspace between the turns of the tubing, comprising the steps of:
- providing an inner cylindrical tank component having a helical ridge thereabout on the outer surface thereof, the ridge having an angled upper surface for receiving a surface of the helical tubing, and a pitch of predetermined spacing along the central axis, and a radial height relative to the central axis that is substantially less than the predetermined radial gap;
- placing over the outer surface of the inner cylindrical tank component a helical heat conductive tube having a mechanically pliant radius relative to the central axis that is greater than the outer radius of the ridge on the outer wall of the inner tank component, the helical tube including an inlet port at one end and an output port extending along the central axis and having a tube diameter less than the predetermined gap size;
- securing the inlet port of the tube from circumferential displacement while depressing the outlet port along the central axis to reduce the helical radius of the tube to contact the ridge on the outer wall of the inner tank component, with substantially the same pitch at the ridges;
- placing an outer tank component above the inner tank component and helical tube;
- stretching the tubing by circumferential movement relative to the inlet port, to establish line contact with the outer tank;
- and
- securing the tank components together with the helical tube in place.
Dependencies are inferred from the claim text.