Coil Temperature Difference: The Core Indicator of Heat Exchange Efficiency in Closed-Circuit Cooling Towers，相关核心信息如下：
1. 常规选型取值范围
- 民用空调工况：标准设计温差为5℃，典型工况为37℃进水、32℃出水。
- 常规工业工况：温差范围为8~20℃，主流档位有65℃-45℃、43℃-33℃、40℃-32℃。
- 高温定制工况：逆流式闭式塔可实现25~40℃的大温差，适配冶金、中频炉等高温场景。
2. 核心计算公式
盘管进出水温差满足热平衡关系：
ΔT=T1−T2=m⋅cpQ
其中Q为热负荷，m为管内流体质量Flow Rate，cp为流体比热容。
3. 关键影响因素
- 环境Wet-Bulb Temperature：出水Temperature比Wet-Bulb Temperature高3~5℃，Wet-Bulb Temperature越低，可实现的温差越大。
- 盘管换热效率：铜管/不锈钢管导热性好，结垢少的盘管能维持更稳定的温差。
- Air Volume与喷淋水量：匹配充足的Air Volume和喷淋量，可强化蒸发换热，提升温差表现。
Written by: Zhongliang Yiji Technical Department · 15 Years of Cooling Tower Selection Experience | Last Updated：2026-10-16
FAQ
How to choose between a closed-circuit and an open cooling tower?
For working conditions that demand clean water (such as vacuum furnaces, high-frequency furnaces, and injection machine hydraulic oil cooling), a closed-circuit tower is preferred: the cooled medium circulates inside the coil without direct contact with air, so it resists scaling, algae and particle contamination, with stable heat transfer and low maintenance. For ordinary recirculating water scenarios with tight water budgets or cost sensitivity, an open tower costs less upfront but requires supporting water treatment.
What are the footprint and connections of a 100 t closed-circuit cooling tower?
Taking a standard 100 m3/h closed-circuit tower as an example: overall dimensions are approximately 3500 x 1500 x 2800 mm with a footprint of about 5.25 m2; inlet and outlet piping is typically DN100, with a 5-10 C temperature drop under standard conditions. Refer to the product specification table for details; non-standard dimensions can be customised on site.
How do I size the pump and head for a cooling tower?
Pump flow is selected according to the rated circulating water volume of the cooling tower; head must account for pipeline friction losses, local resistance, equipment elevation difference and the necessary margin. Pressure-bearing equipment such as injection machines also requires reserve for the working pressure. It is recommended to hand the operating data (flow, temperature difference, installation height, pipe diameter and length) to technical staff for calculation, to avoid an undersized pump or excessive head that wastes energy.
What water treatment does a closed-circuit cooling tower need?
The outer circulating water of a closed-circuit tower still contacts air, so softened make-up water, periodic corrosion and scale inhibitor dosing, and control of the concentration ratio are recommended. The inner circulating medium should be softened water, antifreeze or pure water according to process requirements; outdoor installation in winter requires freeze protection (electric tracing or draining).
