Sintered metal screens are commonly used for fluid particle filtration, gas and air particle filtration. These screens are designed and fabricated by using stainless steel 304l, 316l and high strength super alloys. The metal filter screens are made exactly to suit your requirements for cartridges, vessel and nozzle sizes.
The applications of metal screens range from structural materials to filters. In various cases when they are used in silencers or air filters, the mesh is exposed to dirt. Fouling of mesh screens and acoustic absorbers can alter their properties by blocking holes, altering the pore morphology and reducing the porosity. Since attributes like efficiency, flow resistivity are essential for filter functions and acoustic absorbers, fouling behavior of metal mesh screens is essential to consider. This study observes the fouling behavior of different materials.
Mesh screens are widely used in acoustic sound absorption. The aero-acoustic noise produced by flow around airplane wings can be limited by using porous screens. The screens installed on the wings subjected to dirt can alter their properties by blocking pores and hence decreasing the porosity.
Different materials such as super alloy screens, sintered fiber felts and perforated plates are chosen. The behavior of fouled sintered fiber felts is evaluated. Two sintered fiber felts with different structures were used with different fiber radii and porosities. For the resistance to flow, the layer with small pores is crucial. So, the middle layer with the finest fiber is recommended.
After one month of exposure, the flow resistivity in found to be increased by the dirt. The porosity shows a lower value and the fiber radius an increase is anticipated. For the three layered sintered fiber felt, the tortuosity is found to be same.
Considering the structure of sintered fiber felt, it is complicated to find the dirt in the holes. By using the electron microscopy, it becomes feasible to look only at the top layers of felt. The relatively large pores permit dirt to reach the inner layers of the felt that cannot be observed with the naked eyes. Dirt that results into increased flow resistivity is anticpated to be reached to the middle layer of the felt. A notion to find dirt in the internal layers of sintered fiver felt is by using computer tomography. It develops a 3D image of the felt to observe each layer of felt screen.
The perforated plates and sintered fiber felts are observed microstructurally. The flow resistivity is measured and fouling behavior is evaluated. It is found that flow resistivity increases within six months of fouling. In the perforated plates, the dirt accumulations on the pore walls are found that affects the porosity. Particularly for fine pores, the dirt blocks the holes and alter the cross-sectional pattern of the holes. It is found that using three layered sintered fiber felts, the function of the felt is considerably better than perforated metal and dirt is only found on the top layers of the system.