Encyclopaedia Index

TITLE : Heat Exchanger Simulations

    BY               : D.B. SPALDING and S.V.ZHUBRIN
    FOR              : Technical-discussion meeting
    DATE             : August 1997
    PHOENICS Version : 3.1


The pictures outline and exemplify the way in which HEXAGON, Heat EXchAnGer simulatiON, package will be created and tested.

HEXAGON is a 2D or 3D, steady or unsteady, 1-phase or 2-phase heat exchanger simulator which can be used also for condensers and boilers.

It uses multi-space technique to represent all relevant physics. The model settings have been made by PLANT - the key feature of all future extensions.

A series of PHOTON plots describe the fluid movements and temperature distribution in model heat exchanger.


The picture shows how the solution domain is organised to simulate all relevant phenomena in one computational space.

The distribution of densities show that the tube fluid and shell fluid have different densities, as for water and air.

The viscosities are also different. In the header, tube fluid is turbulent with eddy viscosity proportional to WDIS and local velocity magnitude. The same is true for shell fluid. For some reason in-tube fluid viscosity has smaller viscosity.

The velocity vectors show the movement of of tube fluid in the header, in the U-tube array and zig-zag flow in baffled shell side.

The pressure distribution for tube side flow absorbs pressure losses in header, transmission from free volume to the tube array and in-tube momentum losses.

The overall pressure drop can be seen from legend column.

The pressure distribution in shell side shows that the its range is much smaller than for tube side.

It also allows the overall pressure drop to be deduced.

Overall heat-transfer-coefficient distribution is highly non-uniform.

Temperature distributions for tube side and shell side are as shown.