AIRCOMP will be a program that calculates the airflow rates between rooms, between rooms and the atmosphere, and within the ventilating system. Such a program can be useful when a problem associated with the movements of air is to be studied and should give qualified support for the dimensioning of installations. AIRCOMP has been split-up into two separate parts during its development.
MOVECOMP calculates the air movements in the building, while FLOWCOMP calculates the flow rates in the ventilating system. The advantages to this division are obvious. Results are available during the period of development and it is also easier to control the problem. MOVECOMP was developed and programmed in FORTRAN 77 during 1984, while FLOWCOMP will be developed during 1985. Both input and output data are simple to handle. Only relevant input data are needed and output data are chosen from a menu.
Leakage openings are simulated as power functions . For each room there must be a balance between incoming and outgoing mass flow . Therefore, a node model is used . The number of equations is equal to the number of rooms in the building. A modified Newton-Raphson method is used to solve this system of equation. This method takes the specific problem into consideration more effectively than the conventional Newton-Raphson method. Problems associated with the convergence are effective avoided.
But why develop one more program? During the past 20 years, several computer programs have been developed in this field. In the beginning the models were simple but had serious limitations. A recent survey, including a study of the litterature dealing with the causes of, the calculation of, and the effects of air movements (Herrlin 1983, 1984) showed that these complex programs are not available. The reasons may be either that they are still being developed or that they are not public for commercial reasons. A validation and comparison of these programs have been made at the Air Infiltration Centre (Liddament and Allen 1983).
Units: Dual
Citation: Symposium, ASHRAE Transactions, 1985, vol. 91, pt. 2B, Honolulu, HI
Product Details
- Published:
- 1985
- Number of Pages:
- 8
- File Size:
- 1 file , 460 KB
- Product Code(s):
- D-HI-85-40-1
