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Cooling Towers - Made Easy

A. Bhatia, B.E.


Course Outline

The machines and processes of industry, as well as the air-conditioning systems for buildings generate tremendous amounts of heat, which must be continuously, dissipated to continue to operate efficiently. Water cooling is the most efficient method of dissipating heat.

This 7 -hour online course provides comprehensive information on the different types of cooling towers, their operating principles, mechanical components and the cooling water problems associated with cooling water.

This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.

Learning Objective

At the conclusion of this course, the reader will:


Intended Audience

This course is aimed at chemical, mechanical and HVAC engineers, facility managers, H &S professionals, environmentalists, O & M personal, safety engineers, industrial hygienists, and engineers responsible for the design, purchase or upkeep of heating, ventilation and air conditioning systems.


Benefit to Attendees

This course will raise the level of understanding and awareness of potential users and practitioners involved in design, selection and operation of cooling towers.


Course Introduction

A cooling tower is a device used in industry to cool hot water (by partial evaporation) before reusing it as a coolant. Water directly contacts surrounding air and a very small part (1-2%) evaporate. This evaporation increases the air temperature and humidity and decreases the temperature of the water making it possible to cool below the normal air temperature. Although this heat is usually transferred to a cool, flowing volume of water, final rejection is always to the atmosphere and, invariably, is accomplished by some form of heat exchanger.

The amount of cooling that you get from a cooling tower depends on the relative humidity of the air and the barometric pressure. For example, the more humid the climate the lesser will be the temperature drop and vice versa.

Cooling towers are classified according to the means employed for producing air circulation through them. The towers vary in size from small roof-top units to very large hyperbolic structures that can be over 120 meters tall and 100 meters in length. Smaller towers are normally factory-built, while larger are site constructed.

This course provides more detailed information on the subject.


Course Content

This course is in the following PDF document:

Cooling Towers - Made Easy

Please click on the above underlined hypertext to view, download or print the document for your study. Because of the large file size, we recommend that you first save the file to your computer by right clicking the mouse and choosing "Save Target As ...", and then open the file in Adobe Acrobat Reader. If you still experience any difficulty in downloading or opening this file, you may need to close some applications or reboot your computer to free up some memory.

Course Summary

Evaporative water-cooled systems, whether open or closed-circuit, are the best overall heat rejection solution for most installations. These systems offer design flexibility, save energy, and conserve resources while protecting and respecting the environment.

The most critical value in determining cooling tower efficiency and size is the wet bulb temperature of entering air. Wet bulb temperature is a measurement of maximum cooling capability of air and is a function of the actual (dry bulb) temperature and moisture content (relative humidity) of the air.

Range and Approach are two most important parameters associated with cooling towers. The sizing of cooling tower varies directly as a function of heat load and inversely as range and approach.

To select a cooling tower, the water flow rate, water inlet temperature, water outlet temperature and ambient wet bulb temperatures must be known.

The cooling tower could be natural draft that finds usage mainly in power generation facilities. Most of the industry, process or air-conditioning applications rely on the use of mechanical draft-cooling towers. The mechanical draft cooling towers are further classified as the counter-flow or the cross –flow type depending upon the ‘Fill’ arrangement and the way air comes in contact with water.

The cooling towers use wood, galvanized steel, stainless steel, concrete and fiberglass as the major fabrication materials.

The other important factors that guide the overall performance of the system include the layout & installation considerations to keep the tower free from obstructions, health hazards such as Legionella disease, water treatment, energy efficiency, environment and acoustic concerns.

The testing and performance of cooling tower is governed by the guidelines of Cooling Tower Institute (CTI) standards. The cooling tower industry continues to develop innovative products and services to meet the evolving needs of new and existing facilities.

 

Quiz

Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.