FRP cooling tower Select

Select and use:
When selecting cooling tower, you should understand that, water flow(Q), water inlet temperature(t 1), water outlet temperature(t 2) as well as design well bulb temperature(τ) and define the model in terms of thermal force performance curve.
As to the material cold endurance, the cooling tower is applicable for subzero 50℃region. However, as to regions where the average temperature in the coldest months is lower than subzero 10℃, at the time of making an order, the customer should bring forward anti-freezing measures and the water spray guide ring should be matched to prevent the water from flowing into window shade.
The turbidity of recycled water shouldn’t be higher than 50 mg/l. In short-term, it shouldn’t be higher than 100 mg/l. there shouldn’t be greasy dirt and mechanical impurity in recycled water. When necessary, take measures to remove algae and stabilize water quality.
Refer to foundation drawing at the time of reference. The direction of inlet and outlet pipe of larger cooling tower can be seen in the foundation drawing. The horizontal position of smaller size can be defined randomly, but, it is forbidden to collide with the foundation. If there is foundation in the middle, the load should be 25% of the operation weight and the remaining 75% should be averagely born by the peripheral rectangle foundation. If install the water cooling tower on the roof, consider the additional pressure resulting from the wind load.
The bracket should be set for the cooling tower lower than 125 type to prevent excessive weight from pressuring on the tower wall.
Holes should be opened for water distributor in terms of nominal flux. If the difference between actual flux and nominal flux is larger than 15%, it should be explained at the time of order, the manufacturer will change the open dimensions. The water pressure on the water inlet pipe of the cooling tower is approximate 2～5 meterwater column. Forbid excessive high pressure at the time of design, otherwise, the water will be floated with excessively larger flux.
The product is applicable when the water temperature isn’t higher than 60℃.If the water temperature is higher than 60℃, the order should bring forward at the time of ordering, we will solve this problem by choosing material. If requiring fire resistance cooling tower, explain it at the time of ordering, we can also satisfy this demand. The fin angle of fan of cooling tower higher than 150 type can be adjusted. But, in order to guarantee the uniformity of fin angles, the electric current shouldn’t exceed the normal current of electric power. In short-term, each fin can be inverted to remove ice cake. Therefore, the reversible magnetism starter can be set in the region with serious ice cake. The button should be located near the cooling tower. (The method to adjust the fan can be seen in illustration to counterflow FRP cooling power.)

Cooling Tower Selection

Cooling towers are designed and manufactured in various sizes and configurations. Recognizing and understanding
the different configurations and the advantages and limitations of each is essential to specifying the most cost
effective solution for the end user. The purpose of this bulletin is to highlight the differences between crossflow and counterflow cooling towers and to describe applications where each configuration should be specified.

HOT WATER DISTRIBUTION SYSTEMS

The overall efficiency of a cooling tower is directly related to the design of the tower's hot water distribution system.
The primary consideration in selecting the type of hot water distribution system for a specific application is pump
head. The pump head imposed by a cooling tower consists of the static lift (related to the height of the inlet) plus the pressure necessary to move the water through the distribution system and over the fill. The pump head varies
according to the cooling tower configuration.

Counterflow towers use a high pressure spray nozzle hot water distribution system to achieve water coverage of the
fill. The nozzle spray pattern is sensitive to changes in water flow, and consequent change in nozzle pressure. The air movement is vertically upward through the fill, counter to the downward fall of the water (Figure 1). Counterflow
towers typically have a smaller footprint than crossflow towers, but require additional height, static lift, and dynamic head to achieve the same cooling effect.

Crossflow towers utilize a distinctly different type of water distribution system. Hot water is distributed to the fill by
gravity through metering orifices in the floor of the inlet basin. There is no pressure spray distribution system. The air movement is horizontally through the fill, across the downward fall of the water (Figure 2). In crossflow towers, the internal pressure component of pump head is insignificant because maximum flow is achieved by gravity.

Compared to towers, counterflow towers may require up to five or six psig added pump head to achieve the
proper spray distribution. The high counterflow pumping head requirement (tower height plus nozzle pressure) leads
to a higher first cost pumping system and significantly higher annual pump energy consumption and operating costs.
If the system condenser pumps are not properly sized, the additional pump head required in counterflow towers may result in inadequate hot water flow, reducing tower efficiency and performance.

ADVANTAGES OF CROSSFLOW cooling towers due to their gravity flow hot water distribution system:

1. Low pumping head.
2. Lower first cost pumping systems.

   CROSSFLOW

3. Lower annual energy consumption and operating costs.
4. Accepts larger variation in water flow without adverse effect on the water distribution pattern (flat plate heat exchanger operation in winter).
5. Easy maintenance access to distribution nozzles.

ADVANTAGES OF COUNTERFLOW cool

ng towers due to their pressurized spray water distribution system:

1. Increased tower height accommodates longer ranges and closer approaches.

   COUNTERFLOW

2. More efficient use of air due to finer droplet size from pressure sprays.

DISADVANTAGES OF COUNTERFLOW cooling towers due to their pressurized spray water distribution system:

1. Increased system pumping head requirements.
2. Increased energy consumption and operating cost.
3. Distribution nozzles difficult to inspect and clean.
4. Requires individual risers for each cell, increasing external piping costs.

CONCLUSIONS AND RECOMMENDATIONS

The air and water distribution systems for counterflow and crossflow cooling towers have advantages and
disadvantages inherent in their respective designs. It cannot be said that one is better than the other. Rather, with the proper application, both configurations are cost effective and can serve the end user well.

Crossflow cooling towers should be specified when the following criteria and limitations are important:

1. To minimize pump head.
2. To minimize pumping and piping first costs.
3. To minimize operating costs.
4. When condenser water flow variance is expected.
5. When ease of maintenance is a concern.

Counterflow cooling towers should be specified when the following criteria and limitations are important:

1. When space (footprint) is restricted.
2. When icing is of extreme concern.
3. When pumping is designed for additional pressure drop.

CAUTION: Never replace an existing crossflow tower with a counterflow tower without engineering evaluation to
determine the available condenser water pumping capacity.
If a crossflow tower is specified, a counterflow tower is not an equal alternative.

Cooling tower performance is related to the amount of air moving through the tower and coming into direct contact
with the water.

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