HXAIR - Air Side Options

Use this window to enter details of the AIRSIDE DATA OPTIONS Window where you enter data related to the Airside of the Exchanger. The default values are represented in the window.

RANGE:

LENGTH OF THE BUNDLE - SHOULD BE GREATER THAN ZERO.

AREA PER BUNDLE - SHOULD BE GREATER THAN ZERO.

NUMBER OF ROWS/BUNDLE - GREATER THAN OR EQUAL TO ONE.

NUMBER OF PASSES/BUNDLE - SHOULD BE BETWEEN 1 AND 16.

NUMBER OF TUBES/BUNDLE - ANY POSITIVE VALUE

Usage

HOTSIDE=TUBE

Specifies the side of the exchanger receiving the hotside fluid. Enter TUBE or AIR.

FLOW=COUNTERCURRENT

Specifies the flow direction. This entry affects the calculation of the LMTD correction factor (FT) and, thereby, the MTD. Enter COUNTERCURRENT to specify that the tubeside and airside fluids flow in opposing directions, or COCURRENT to specify flow in the same direction. The default is COUNTERCURRENT.

AREA

Rating only. Specifies the effective or "installed" area per bundle. The area covered by the tubesheets and baffles is subtracted from the outside area of the tubes. For finned tubes, fin area must also be included in the total bundle area. This value is checked for consistency with the tube information.

Rows per Bundle

Enter the number of tube rows in the bundle:

O O O O O O O

O O O O

3 rows/ 2 rows/

Number=12 Number=6

If you know the total number of tubes and the duct dimensions, PRO/II can calculate the number of rows per bundle.

Airside or Duct side Data

The Program can calculate the duct dimensions from the data supplied for a tube bundle. These data are used to calculate the gas flow velocity. PROII will calculate default values if these data are not provided.

Width

Enter the width of the bundle. If you do not enter a value, calculates the bundle width using the following formula:

Width = (Tubes/Row) * (Transverse Pitch)

For a design (new) case, this entry represents the bay width as only one bundle is designed in each bay.

Length (Duct)

Enter the length of the bundle inside the duct. If you do not enter a value, PRO/II sets the duct length equal to the tube length.

Bays in Parallel

For a rating case, enter the number of identical bays in parallel. For a design case, enter the minimum and maximum number of identical bays allowed in parallel in the Design Constraints dialog box.

Check Data:

This option performs the geometry consistency checks. If this option is not enabled then the user is expected to provide geometrically consistent data. Incorrect or omitted data can cause fatal errors while execution.

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