Process and apparatus utilizing common structure for combustion, gas fixation, or waste heat recovery

In a thermal system, apparatus for increasing convection efficiency, comprising:

• an enclosure having an inlet opening, an outlet opening, and a predetermined longitudinal axis;
• means for supplying a substantially gaseous primary fluid at said inlet opening;
• means for establishing a static pressure differential between said inlet and outlet openings to cause said primary fluid to flow continuously through said enclosure;
• a thermal transfer wall exposed to said primary fluid in said enclosure;
• means containing a secondary fluid in flow isolation from said primary fluid and in thermal conduction relationship with said primary fluid through said thermal transfer wall;
• and
• means for establishing a highly turbulent and relatively low thermal transfer resistant film of said primary fluid on said thermal transfer wall in said enclosure, said last-mentioned means comprising rotatable blade means for swirling said primary fluid at high velocities along said thermal transfer wall.

In a thermal system, apparatus for increasing convection efficiency, comprising:

• an enclosure having an inlet opening, an outlet opening, and a predetermined longitudinal axis;
• means for supplying a substantially gaseous hot primary fluid at said inlet opening, said gaseous primary fluid having water vapor therein;
• means for establishing a pressure differential between said inlet and outlet openings to cause said primary fluid to flow continuously through said enclosure;
• a thermal transfer wall exposed to said primary fluid in said enclosure;
• means containing a secondary fluid in flow isolation from said primary fluid and in thermal conduction relationship with said primary fluid through said thermal transfer wall;
• rotatable means for mechanically stirring said primary fluid in said enclosure, said rotatable means comprising zone-establishing means for establishing a plurality of thermal zones at successive longitudinal locations in said enclosure, said zone-establishing means comprising:
• means in each zone for re-circulating said primary fluid radially from said longitudinal axis, longitudinally along said thermal transfer wall, and radially back to said longitudinal axis, to cause water vapor in said primary fluid to alternately condense on said thermal transfer wall, then be swept away from the wall by the re-circulating primary fluid and then evaporated.

Heat exchange apparatus comprising:

• an enclosure having peripheral walls extending longitudinally between first and second end walls;
• inlet means for admitting a primarily gaseous primary fluid into said enclosure proximate said first end;
• outlet means for passing said primary fluid out of said enclosure proximate said second end;
• fluid flow-inducing means for establishing a relatively low rate of net flow of said primary fluid through said enclosure from said inlet means to said outlet means;
• means for containing a secondary fluid isolated from said first fluid;
• energy transfer means for providing thermal energy transfer between said primary fluid and said secondary fluid in said enclosure;
• a rotatable shaft having a longitudinal axis extending longitudinally through at least a portion of said enclosure;
• blade means responsive to rotation of said shaft for swirling the primary fluid along a path which is bounded at least in part by said energy transfer means;
• and
• drive means for rotating said shaft about its longitudinal axis to impart a swirl velocity component to said primary fluid which is much larger than said net flow rate.

A method for increasing convection efficiency in an enclosure having a longitudinal axis, said method comprising the steps of:

• supplying a substantially gaseous primary fluid at an inlet opening in said enclosure;
• establishing a pressure differential between said inlet opening and an outlet opening of said enclosure to establish a continuous flow of primary fluid through said enclosure;
• maintaining a secondary fluid in flow isolation from said primary fluid and thermal conduction relationship with said primary fluid through a thermal transfer element;
• mechanically stirring said primary fluid in said enclosure, said stirring including the step of imparting a rotative flow component to said primary fluid about said longitudinal axis and along said thermal transfer element, the rate of said rotative flow component being at least very much greater than the primary fluid net flow rate through said enclosure;
• and
• flowing said secondary fluid through a confined flow path bounded at least in part by said thermal transfer element;
• wherein the mechanical stirring of said primary fluid is accomplished by the steps of:
• rotating a rotatable shaft about said longitudinal axis;
• and
• rotating plural blade members together with said shaft about said longitudinal axis to provide a net helical flow for said primary fluid through said enclosure, said helical flow representing the vectorial sum of said longitudinal flow and said rotatable shaft.

A method of heat exchange comprising the steps of:

• establishing flow of a first gaseous fluid containing water vapor through an enclosure in contact with a thermal transfer wall;
• flowing a second fluid in contact with said thermal transfer wall to permit thermal transfer between said first and second fluids;
• establishing a plurality of thermal zones at successive longitudinal locations in said enclosure;
• graduating the temperatures in successive zones along the length of said enclosure;
• in each zone, swirling said first fluid therein along a path which in part includes said thermal transfer wall;
• in each zone, condensing said water vapor on said thermal transfer wall;
• sweeping condensed water back into the swirling flow;
• vaporizing the water swept back into the swirling flow;
• and
• repeating the above three steps to establish a cycle of condensation and vaporization in each of said zones;
• wherein said step of swirling comprises the steps of:
• rotating a first plurality of blades at a first location about an axis extending along the nominal flow direction of said first fluid through said enclosure;
• and
• in response to rotation of said plurality of blades, establishing a pair of said zones, one upstream and the other downstream of said first plurality of blades, each zone being defined by plural flow components having a net flow pattern which extends radially from said axis then along said thermal transfer wall and then back toward said axis.

A method of heat exchange comprising the steps of:

• establishing flow of a first fluid through a enclosure in contact with a thermal transfer wall;
• flowing a second fluid in contact with said thermal transfer wall to permit thermal transfer between said first and second fluids;
• establishing a plurality of thermal zones at successive longitudinal locations in said enclosure;
• graduating the temperatures in successive zones along the length of said enclosure;
• and
• in each zone, swirling said first fluid therein along a path which in part includes said thermal transfer wall;
• wherein said step of swirling comprises the steps of:
• rotating a first plurality of blades at a first location about an axis extending along the nominal flow direction of said first fluid through said enclosure;
• and
• in response to rotation of said plurality of blades, establishing a pair of said zones, one upstream and the other downstream of said first plurality of blades, each zone being defined by plural flow components having a net flow pattern which extends radially from said axis then along said thermal transfer wall and then back toward said axis.

In a process of efficiently utilizing accessory power to maximize the convective heat exchange between a flowing gaseous stream and a heat exchanger housing, the steps comprising:

• maintaining a static pressure differential between a first end and a second end of the heat exchanger housing which provides negligible internal flow resistance to said gaseous stream to flow the gaseous stream from the first end to the second end of the heat exchanger housing at an average axial velocity;
• driving a mechanical stirring element located within the gaseous stream from a location outside the stream;
• and
• mechanically stirring the gaseous stream with said stirring element along the inner surface of the heat exchanger housing at an angular velocity which is large relative to said axial velocity of the gaseous stream;
• wherein accessory power required to maintain the static pressure differential across the heat exchanger is low and the power required to drive the stirring element is fully utilized to augment the convective heat exchange process.