Fans Ventilation A Practical Guide

Drying

A drying system is often necessary in industry: • to reduce the moisture within a material to improve it • to make industrial processes more efficient • to recover the moisture where this has value. Moisture may be present in a solid material in various forms as: • surface moisture • absorbed moisture • water […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

Tunnel ventilation

Ventilation of tunnels is necessary to remove pollution or heat and to control smoke in the event of fire. Pollution in road tun­nels is caused by the emission of carbon monoxide, diesel smoke and the oxides of nitrogen from vehicles. In rail tunnels, it can come from locomotive diesel smoke while, in metros, heat removal […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

Residential ventilation

The UK situation For many years we have been accustomed to providing some form of ventilation in two particular areas of a home. These par­ticular applications are characterised by high levels of humidity and are as follows: • Bathroom extract • Cooker extract Under previous conditions, these two areas were perhaps unique in British houses […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

Figure 21.5 Direct drive mixed flow unit with side discharge Extract ventilation

Wall mounted propeller fans have been used in the extraction mode since the very earliest days of mechanical fans. Refer­ence to Chapter 1 shows that these were popular from the 1880s. Usually positioned in the gable ends of buildings, they are still a feature of many older industrial buildings. Following the 2nd World War, special […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

Fresh air requirements for human comfort

Indoor air quality Over the last few years considerable research has been con­ducted both here and in the USA to determine what pollutants exist in the ambient atmosphere and within buildings. These studies have principally looked at the prevalence of volatile or­ganic compounds, pesticides, carbon monoxide and particulates. Whilst we are all aware of reports […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

Some fan applications

This Chaptergives some indication of the many uses forfans. Fans & Ventilation is not intended to be a text book on ventilation and or air conditioning. Rather it seeks to address the problems that exist at the interface between fan manufacturers and users. Furthermore it hopes to show that there are many uses for fans […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

Purchasing

Many of the chapters in this book deal with the criteria and stan­dards which are of importance in correctly specifying a fan. Chapter 17 deals with the implementation of testing and quality control. These are concerned, among other topics, with guar­antees of performance and quality. Criteria for service life and reliability have not yet been […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

Mathematical tools

Most fan duties can be met by selecting an appropriate fan size from a standard range. It is just a case of choosing the best size and type from those which are available or pre-designed. Theo­retically, if it could be run fast enough, a single fan could meet all duties. Whilst much to be desired […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

General operating conditions

Everything about a fan application is important. Potential pur­chasers should not make value judgments on what information is, or is not important. It may well be that the missing data will devalue the manufacturer’s warranty. Guarantees are given for specified operating conditions. If there are operating conditions which have not been included in the specification, […]

Posted in: Fans Ventilation A Practical Guide | No Comments »

Fan selection

This Chapter is concerned with the general choice of fan and ancillaries and is aimed primarily at the user. It must however, be emphasised that the choice should be finalised after detailed discussions with a reputable supplier. In the following Sections, the fan is chosen on the basis of the desired flowrate, fan pressure, air/gas […]

Posted in: Fans Ventilation A Practical Guide | No Comments »