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A numerical model of an unsteady laminar free convection flow and heat transfer is studied in a cavity that comprises a vertical flexible thin partition.

The left and right vertical boundaries are isothermal, while the horizontal boundaries are insulated. Moreover, the thin partition, placed in the geometric centerline of the enclosure, is considered to be hyper elastic and diathermal. Galerkin finite-element methods, the system of partial differential equations along with the appropriate boundary conditions are transformed to a weak form through the fluid-structure interaction and solved numerically.

The heat transfer characteristics of the enclosure with rigid and flexible partitions are compared. The effect of Rayleigh number and Young’s modulus on the maximum nondimensional stress and final deformed shape of the membrane is addressed.

Incorporation of vertical thin flexible membrane in middle of a cavity has numerous industrial applications, and it could noticeably affect the heat and mass transfer in the enclosure.

In stereolithography (SL), the total exposure absorbed by photopolymer is variable and is a function of height. This phenomenon causes heterogeneous properties and develops residual stresses during process. Consequently, a pronounced deformation occurs especially when small and more intricate objects are fabricated. The purpose of this paper is to predict this deformation when miniature and complicated parts are fabricated.

In this paper classical lamination theory is employed to model mechanical properties of layers, layers shrinkage and residual stress growth during SL process. Distortion is predicted based on the developed model.

Results show that final distortion is proportional to part thickness and it increases exponentially as parts thickness or layers thickness decrease.

To verify the results, several test pieces were built with SLA 5000 machine and SOMOS 11120 resins. Their distortions were measured with video measuring machine (VMM‐3020D machine). The estimation agrees very well with the experimental results (less than 10 per cent error).

The paper considers the heterogeneous properties of SL parts during fabrication process; an item which was ignored in previous researches. This theoretical and experimental study provides useful information about estimation of deformation of SL parts after building. This information helps the SL machine user to select the best parameters when fabricating miniature and intricate features, especially for biomechanics parts.

The purpose of this study is to investigate the influences of the supports on tensile strength (TS) of stereolithography (SL) parts.

The shape of specimens (tensile specimens) is according to the American Society Testing and Materials (ASTM) D638 standard. Some parts have support trace on one side and some have support trace on both sides. To achieve this target, some parts are fabricated on other parts; therefore, support of the upper part is fabricated on upper face of lower part.

Influences of supports traces on mechanical properties aren’t “zero”. Supports affect TS of SL parts by affecting surface roughness of parts. After experimentation and analyzing experimental results, it is concluded that the TS of the parts which have support on both sides is slightly lower than the parts which have support just on one side.

This is the first attempt toward investigation of supports effects on the mechanical properties in SL parts.