All-welded plate heat exchanger tube side collection boxes mainly by the upper and lower side-tube plate, the upper and lower connecting plate, front and rear side-tube side plates to form a rectangular cross-section of the container, which tube-side end plate and the connecting plate lap together. In the tube side collection box outside the ring and flange welded to strengthen played reinforcing. Tube side collection boxes of the calculation conditions such as shown in Table l. The mechanical properties, such as shown in Table 2.
2 all-welded plate heat exchanger tube side collection box structure analysis and mechanical model of
According to tube-side collection boxes of structural characteristics and engineering requirements, using ANSYS software, pre-treatment procedures PREP 7, through the unit type selection, the determination of material parameters, geometric modeling and cell generation of steps to establish a management-side collection boxes of finite element analysis model and finite element meshing of the model. In this paper, Shell 63 elastic four-node element 63 bottom-up modeling approach to establish the finite element model, are the deformation and stress analysis of the structure.
2.1 connecting plate and tube-side end plate of the mechanical model of overlap
According to structural characteristics and load characteristics of the finite element model, taking the tube side collection boxes of 1 / 4 for analysis. Shell finite element model.
2.2 Constraints
As the models take the whole 1 / 4 of the analysis, so the model symmetry constraints imposed by the symmetry plane. Beam connecting plate and the plate connected to a fixed position to impose constraints, the management side to side side plates to impose a fixed constraint.
2.3 Finite Element selection
(1) defines the unit type
Structure using ANSYS 9.0 software, the flexibility of four-node 63 units (SheB elastic 4node 63). Shell63 elastic shell: a moment and film properties, affordable, and the plane in the same direction and the normal direction of the load. Each node, six degrees of freedom: X, Y, direction and around the X, Y, axis. Of stress and large deformation capacity to strengthen and provide continuity for large deformation analysis of tangent matrix.
(2) the definition of material properties
Connecting plate and end plate to set the elastic modulus E is 190GPa, Poisson's ratio μ 0.29; set the reinforcement ring and the flange of the elastic modulus E is 200GPa, Poisson's ratio μ is 0.2 all-welded plate heat exchanger 8.
(3) meshing
Meshing meshing means freedom of choice.
2.4 applied load
The inner surface of the model imposed by 0.2 MPa pressure.
3 results
The results include the tube side of the stress and the collection box equivalent stress and deformation analysis.
3.1-side collection boxes of the stress and equivalent stress
3.2 The calculation results
As can be seen from Table 3, the greatest stress appears in the tube side side-plate mid-point, that is, rectangular cross-section at the midpoint of the long side, which is estimated based on the engineering experience, the value of the maximum stress position coincide. Proved that the model and calculated results is in line with reality.
4 Conclusion
By ANSYS analysis, from the node displacement and stress field of cloud cloud can be seen more directly to changes in stress conditions and location of maximum stress and improve the calculation accuracy, the calculation results can be used as all-welded plate heat exchanger connecting plate and deformation of the structural design analysis of the theory. This calculation method can be widely used in engineering practice.