Single‑Side Combined‑Flow Closed‑Circuit Cooling Tower
The XLH Series features a design in which cooling air enters horizontally from only one side of the tower, creating a combined cross‑flow heat exchange with the downward spray water over both the coil and the PVC fill section. The tower is divided into two heat‑exchange zones: an upper coil zone and a lower fill pre‑cooling zone. Ambient air enters through the inlet grille on one side, flows horizontally across the coil bundle to absorb heat from the spray water film, then continues through the fill layer for a secondary heat exchange with the falling spray water, further reducing its temperature before it is recirculated to the coil surface. This configuration retains the water‑quality advantages of a closed‑loop system while using the fill to share part of the thermal load, which helps mitigate scale formation on the coil. The compact, single‑side air intake also allows flexible placement—close to walls or along plant boundaries—making it well suited for sites with limited installation space. Specifications Heat capacity: 87 – 1,744 kW Flow rate: 66 – 1,321 gpm / 15 – 300 m³/h Type: Combined‑flow / Axial fan / Induced draft Typical Applications (focused on space‑constrained single‑side installations and medium‑load duties): Medium‑sized commercial HVAC – providing cooling water for shopping malls, office buildings, and hospitals where installation space is limited. Food and beverage processing – jacket cooling, condenser cooling, and other processes that require clean water quality. Electroplating and surface treatment lines – supplying stable cooling water for rectifiers, heat exchangers, and associated equipment. Small‑scale data center auxiliary cooling – supporting air‑conditioning systems for edge computing nodes and medium‑to‑small server rooms.
How it works?
The single‑side combined‑flow closed‑circuit cooling tower operates on three synergistic mechanisms: closed internal circulation, external spray circulation, and single‑side combined‑flow heat exchange. Its defining feature is that cooling air enters horizontally from only one side of the tower, forming a cross combined‑flow with the downward falling spray water over the coil and fill zones. The process fluid to be cooled (softened water, antifreeze, or specialty fluids) circulates in a closed loop within the heat exchange coil, fully isolated from outside air to prevent scaling and contamination. Meanwhile, the spray pump draws water from the collection basin and delivers it to the top distribution system, which evenly sprays it over the outer coil surface to form a continuous water film. The water film absorbs heat from the fluid inside the coil, then falls downward through the PVC fill section and returns to the basin, completing the external circulation loop. Cooling air enters through the inlet grille on one side of the tower and passes sequentially through the coil heat‑exchange zone and the fill pre‑cooling zone. In the coil zone, the air flows horizontally across the coil bundle, exchanging heat with the falling water film and removing both sensible and latent heat. In the fill zone, the air undergoes a secondary heat exchange with the spray water, further reducing its temperature. Unlike dual‑side inlet designs, the single‑side airflow travels horizontally across the tower before turning upward and merging with make‑up air from the top inlet. The saturated air then passes through the drift eliminator to remove entrained droplets before being discharged. The cooled spray water returns to the basin for recirculation, while the process fluid returns to the equipment, completing the closed‑loop cycle.
Structure & Characteristics
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1 、Heat Exchange Coil:
Process fluid circulates inside the coil in a closed loop, with heat transferring through the tube wall to the external spray water—this is the core of a closed-circuit tower. Standard coils are 304 stainless steel, with options for 316L, copper, or duplex steel. All coils are pressure-tested for leak-proof performance. Multi-layer serpentine layout with optimized tube spacing allows smooth air passage and efficient heat transfer.
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2 、Fan:
The fan drives airflow across the coil and fill media to carry away heat; airflow volume directly affects cooling performance. All units feature special axial fans with nylon or aluminum blades, galvanized steel supports and guards. Motors are IP55-rated, Class F insulation, with optional VFD for energy-saving speed control.
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3 、Spray Pump:
The spray pump draws water from the basin and delivers it to the top distribution system, powering the external circulation loop. Xuelun uses high-performance branded pumps with high flow, low power draw, and quiet operation. Pump bodies and impellers are available in cast iron or stainless steel to suit different water quality conditions.
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4 、Water Distribution System:
The distribution system sprays water evenly over the coil surface to form a continuous film—uniform coverage directly impacts heat transfer efficiency. On counterflow towers, the system sits at the top, using high-capacity ABS basket-type nozzles that resist clogging and are easy to remove for cleaning.
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5 、Air Inlet Louver:
The inlet louver guides air evenly into the tower while blocking debris like leaves, insects, and dust to prevent coil and nozzle fouling. It features PVC fill with a metal frame and is fully removable—simply lift upward and pull outward from the bottom for convenient cleaning.
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6 、Drift Eliminator:
The drift eliminator sits below the fan or at the air outlet, using inertial impingement to capture fine water droplets from the moist air and return them to the basin, reducing water loss. Made of corrosion-resistant PVC, it limits drift loss to under 0.1%.
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7 、Fill:
The unit uses Marley PVC fill, installed beneath the coil. Its honeycomb cross‑flow structure spreads the spray water into a broad film. As air sweeps across, it removes heat, pre‑cooling the spray water and thereby sharing the coil’s thermal load. The fill offers low air resistance, resists aging, and maintains its shape, making it well suited for prolonged hot and humid conditions.
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8 、Casing:
The casing provides structural support and weather protection for internal components, shielding them from rain, sun, and spray corrosion, while also reducing noise and improving appearance. Constructed from ZAM-coated steel or 304 stainless steel, laser-cut for precision—offering superior corrosion resistance over standard galvanized or FRP shells.
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9 、Collection Basin:
Located at the base, the basin collects spray water and provides a stable suction source for the spray pump. The basin is typically made of the same material as the casing—ZAM-coated steel, with 304 or 316 stainless steel available as upgrades for enhanced durability in demanding environments.
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10 、Base Frame:
The base frame supports the entire tower, transferring weight to the ground and ensuring stable, level operation. Constructed from galvanized channel steel; stainless steel is available as an option for applications requiring additional corrosion protection in humid or chemically aggressive environments.
Basic norm
