The only software fully implementing T-Method Duct Simulation (ASHRAE Handbook 1993, chapter 32). The program will evaluate the performance of a fan/duct system under various conditions, adjust the fan operating point, and display actual airflow, mass flow rate, velocity, and pressure profile at each duct section. Play "what-if" scenarios. Large fitting library. Menu driven. User friendly. Design/retrofit/modeling/test and balancing/fire protection. Supply/exhaust/return systems.

THE ONLY COMPUTER SOFTWARE WHICH ALLOWS YOU TO SIMULATE, ANALYZE, DESIGN, CHECK, AND MODEL THE PERFORMANCE OF A DUCT SYSTEM

"T-Method is an excellent design tool for simulating flow distribution within a system with various modes of operation"

THE PROGRAM IS RECOMMENDED FOR:

PROGRAM FEATURES

T-DUCT creates numerical models of duct systems. It is based on ASHRAE's T-Method duct simulation technique which governs two basic principles of ventilation: conservation of mass and conservation of energy.

With T-DUCT you may simulate changing cross-sections, close or open dampers, remove/add/modify fittings and duct-mounted equipment, select different diffusers, change fans and/or motors. In response the computer will adjust the fan-system operating point and show the actual airflows, velocities, pressure profiles and how they differ from the preceding design.

T-DUCT is the first duct calculation computer program that satisfies the conservation of mass law by pressure balancing using mass flow rates rather than volumetric flow rates.

T-DUCT will calculate recommended fan pressure for your duct system.

Program Capabilities are . . .
• Complete fitting libraries: ASHRAE, SMACNA, Idelchik, totaling 303 fitting and equipment tables
• Interactive user-friendly window-driven input
• Supply/exhaust/return systems, residential, commercial and industrial
• Browse/copy/move/edit/insert/delete capabilities
• Round/rectangular ducts, all fans and duct materials
• Damper open/close capability including fire/smoke dampers
• Automatically converts from/to IP/SI/Metric units as required
• Private directories for each project or user
• Air temperature and density calculation at each duct section
• Air mass flow rates and pressure losses balancing
• Fan curve and pressure loss correction due to high/low elevation and/or changes in air temperature

T-DUCT is developed under direct consulting and supervision of Mr. Herman F. Behls and Dr. Robert J. Tsal, the authors of ASHRAE 1989 and 1993 Handbook, "Duct Design" chapter.

Fitting/Equipment Libraries include . . .

Entries, Exits, Louvers, Elbows, Transitions, Junctions, Dampers, Obstructions, System effect factors, Room air terminal devices, Coils, Heat exchangers, Filters, Sound traps, Air monitor devices, Air washers and eliminators, Additional C-coefficients and required pressure losses.

T-DUCT allows playing "what-if" evaluations like ...

"what happens when one or more fans in a parallel-fan system shuts down?" or "what is the effect on a smoke control system's performance during a fire when some fire/smoke dampers close, and others remain open?"

Converging

the example in ASHRAE (19-section system) requires 7 iterations and takes approximately 40 seconds (IBM 386-25), 9 seconds (IBM 486-33), or 1 second (Pantium 133) and has an accuracy greater than 99%.

Developed

in C language, easy installation, interactive window-driven fitting selection. Program VERIFICATION AND VALIDATION is included into the manual.

APPLICATION EXAMPLES
• Parallel fan-system operating condition when one or more fans shut down
• Flow distribution in a variable air volume (VAV) system due to terminal box flow diversity
• Pressure differences between adjacent confined spaces within a nuclear facility when a design basis accident (DBA) occurs
• Airflow redistribution due to HVAC system additions and/or modifications
• System airflow analysis for partially occupied buildings
• Replacing fans and/or motors when retrofitting an air distribution system
• Smoke control system performance during a fire when some fire/smoke dampers close, and others remain open
• Pneumatic conveying system and manifold analysis
• Effect of damper blade modulation at various angles on airflow.

T-DUCT Title Screen	T-DUCT Fitting Selection Screen
Fan-System Curves Screen	T-DUCT Pressure Profile Screen
T-DUCT Sections Screen