GMB Architects+Engineers Inc. is the first engineering firm to use 3-D modeling for airflow, temperature and humidity performance in an indoor pool design project.

After 18 years experience in consulting engineering, James Harrison, Jr., admits that natatoriums are still one of the HVAC industry's most challenging design applications, due mainly to their huge evaporative rates.

Consequently Harrison, a mechanical engineer at GMB Architects+Engineers Inc., Holland, MI, didn't hesitate for a moment when offered the world's first natatorium Computational Fluid Dynamics (CFD) analysis for his ninth indoor pool project-the huge 16,500-square-foot natatorium of East Kentwood High School, in the Grand Rapids, MI, suburb of Kentwood.

Harrison believes his past designs have been sound; however, huge natatoriums such as East Kentwood's are never a sure bet because of the multitude of variables that must be analyzed and evaluated to arrive at a final design concept. Consequently, consulting engineers are sometimes victimized by factors beyond their control, such as variances in ductwork and fittings manufacturers' specifications. Also, field airflow modifications due to architectural or structural changes, not to mention start-up and testing/balancing problems, can change original concepts once the system is finally in operation.

Add all these concerns to a 9,650-square-foot pool expected to produce a huge humidity load of over 550 lbs./hr. of moisture, and Harrison and East Kentwood Public Schools construction officials gladly accepted the offer of Dan Kasper, sales engineer, Michigan Air Products, Grandville, MI, to be the first CFD analyzed natatorium customer. The "Aire-Tech-Chek™,"