Back to results
US 2014/0209279 A1Published application
Indirect heat exchanger
AssigneeBaltimore Aircoil Company, Inc.
InventorsDavid Andrew Aaron, Zan Liu, Philip Hollander
Life of this patent
Estimating the term…
Abstract
A heat exchange apparatus is provided with an indirect evaporative heat exchange section. An evaporative liquid is downwardly distributed onto the indirect section to indirectly exchange sensible heat with a hot fluid stream flowing within a series of enclosed circuits which comprise the indirect evaporative heat exchange section. An ideal flow rate for such evaporative liquid is between 2.5 and 3.5 gallons per minute per square foot of top surface area of the indirect heat exchange section.
Claims10
A method of operating an indirect heat exchanger comprising:
- providing an indirect heat exchanger comprising
- a plurality of coils having length sections and bend sections,
- a fan to draw air across the plurality of coils,
- a water distribution system located above the plurality of coils and
- comprising
- a series of discharge sections, an inlet header connected to the series of discharge sections,
- a plurality of openings in each discharge section that allow water to be distributed downwardly over the plurality of coils and a sump to collect the water after passing over the plurality of coils,
- wherein the water distribution system also comprises an exit opening in the sump, and a pump connected to the exit opening, and a return line to supply the water from the sump to the inlet header of the water distribution system,
- wherein the pumping capacity at any given time results in water being discharged from the water distribution system onto the plurality of coils according to:
- DZP=Cf*NROWS*[(NCKTS*Dp)/Cw]̂2 Equation 1
- Where:
- DZP=Density Zone Profile Number
- Cf=correction factor for fins described in table 1
- NROWS=number of tubes fed from top to bottom
- NCKTS=number of circuits in a casing width
- Dp=projected tube diameter, inches
- Cw=casing width, inches
- Where DZP is the density zone profile of the plurality of coils,
- And the water distribution system discharges water into the plurality of coils at a rate of between 20.0 and 4.0 gallons per minute per square foot of top surface area of the plurality of coils.
16 more elements
A method of operating an indirect heat exchanger comprising:
- providing an indirect heat exchanger comprising
- a plurality of coils having length sections and bend sections,
- a fan to draw air across the plurality of coils,
- a water distribution system located above the plurality of coils and
- comprising
- a series of discharge sections, an inlet header connected to the series of discharge sections,
- a plurality of openings in each discharge section that allow water to be distributed downwardly over the plurality of coils and a sump to collect the water after passing over the plurality of coils,
- wherein the water distribution system also comprises an exit opening in the sump, and a pump connected to the exit opening, and a return line to supply the water from the sump to the inlet header of the water distribution system,
- wherein the water being discharged from the water distribution system onto the plurality of coils is between 2.0 and 4.0 gallons per minute per square foot of the surface area of the plurality of coils.
6 more elements
A method of operating an indirect heat exchanger comprising:
- providing an indirect heat exchanger comprising
- a plurality of coils having length sections and bend sections,
- a fan to draw air across the plurality of coils,
- a water distribution system located above the plurality of coils and
- comprising
- a series of discharge sections, an inlet header connected to the series of discharge sections,
- a plurality of openings in each discharge section that allow water to be distributed downwardly over the plurality of coils and a sump to collect the water after passing over the plurality of coils,
- wherein the water distribution system also comprises an exit opening in the sump, and a pump operatively connected to a return line to supply the water from the sump to the inlet header of the water distribution system,
- wherein the pump can be operated to provide water from the sump to the inlet header at a water discharge rate,
- the water discharge rate being calculated according to:
- DZP=Cf*NROWS*[(NCKTS*Dp)/Cw]̂2 Equation 1
- Where:
- DZP=Density Zone Profile Number
- Cf=correction factor for fins described in table 1
- NROWS=number of tubes fed from top to bottom
- NCKTS=number of circuits in a casing width
- Dp=projected tube diameter, inches
- Cw=casing width, inches
- Wherein DZP is the density zone profile of the plurality of coils, and the water discharge rate is be 2.0 and 4.0 gallons per minute per square foot of top surface area of the plurality of coils when 02P is greater than 10.
16 more elements
A method of operating an indirect heat exchanger comprising:
- providing an indirect heat exchanger comprising
- a plurality of coils having length sections and bend sections,
- with each coil having an inlet opening and an exit opening,
- an inlet coil header connected to the inlet opening of each coil and
- an outlet coil header connected to the outlet opening of each coil,
- the plurality of coils formed into a coil structure,
- a fan to draw air through the coil structure,
- a water distribution system located above coil structure,
- the water distribution system comprising
- a plurality of water discharge sections,
- an inlet distribution header connected to the plurality of water discharge sections,
- a plurality of openings in each water discharge section that allow water to be distributed downwardly over the coil structure,
- and a sump to collect the water after passing over the coil structure,
- wherein the water distribution system also comprises an exit opening in the sump, and a pump connected to the exit opening, and a return line to supply the water from the sump to the inlet distribution header,
- wherein an airside static pressure drop of the coil structure is measured as SP,
- wherein the pump can operate at various speeds to provide varying pumping rates,
- and wherein the pumping rate can be varied to adjust a total water discharge rate from the plurality of water discharge sections onto the coil structure according to a formula
- that if SP is greater than 1 inch of water column, the total water discharge rate onto the coil structure is between 2 and 4 gallons per minute per square foot of surface area of the coil structure.
15 more elements
Dependencies are inferred from the claim text.