Software provides help to those responsible for tower evaluation, prediction and monitoring.

Software designed for evaporative-cooling tower users by the Cooling Technology Institute, Houston, provides help to those responsible for tower evaluation, prediction and monitoring.

Using Microsoft Windows, the CTI ToolKit predicts off-design performance with demand-curve tabs. It answers "what-if" questions such as how much the leaving-water temperature will change if water flow is increased 10%.

The demand-curve tab speeds the evaluation of the characteristic-curve method, calculating the tower's overall capability when a manufacturer's performance curves are unavailable. Users can produce demand-curve pages on any printer for an exact set of design conditions at any altitude.

The performance-curve tab automatically calculates cooling tower performance using the CTI ATC-105 test method. It automatically solves the iterative calculations for the exit-air temperature and psychrometric properties to compute the test L/G as required by CTI ATC-105, and it interpolates between curves, generating necessary cross-plots to determine overall tower capability.

Users can produce their own performance curves from field-test data. With the demand-curve tab application and a single test point, they can create a set of performance curves along with any spreadsheet.

According to CTI, the performance-curve method is widely recognized as an accurate way of determining cooling tower capability from measured test data. The ToolKit's tab application "provides a quick and easy method for anyone to evaluate a performance test using this more accurate method," said Rich Harrison Jr., chairman of CTI's ATC-105 Task Group.

A single-user license for CTI ToolKit V 2.0 is $395 for CTI members and $450 for nonmembers. The cost to upgrade an existing Toolkit V 1.0 is $95 for members; $120 for nonmembers. The stand-alone performance-curve application, PerfCurv 1.0 is $195 for members; $240 for nonmembers.

To contact CTI, call (281) 583-4087; fax (281) 537-1721; or go to the web at