Air and gas flow

It is an unfortunate fact that the relationship between academics and engineers in the ventilation industry is less than perfect. The former produce theories from their research which rarely get transferred to industry. In like manner, the latter may install plant for which the working data is never relayed back to academia. Worse, balancing subcontractors endeavour to put right the mistakes made in design. Even worse, system pressures are “guessed” (with a large safety margin). Too many fan enquiries specify 500 Pa for exhaust systems and 1500 Pa for the supply air handling unit.

We have not completely finished with basic theory and it is necessary to introduce the work of three further scientific giants — Newton, Euler and Bernoulli. An appreciation of their work is essential as they give the foundations for fan engineering.

This Chapter on air and gas flow, therefore attempts to bring the science and engineering together for the mutual benefit of the two sides. It emphasises, it is hoped, the need for more auditing of actual plant. How does actual performance compare with design intentions? Certainly there is a need to feed back the actual site data to the universities and a company’s data bank.

Posted in Fans Ventilation A Practical Guide