Flow medium
A flow medium for distributing a resin in vacuum assisted resin transfer molding processes for manufacturing long, thick and more complex composite parts comprises a flow channel encapsulated by a layer of fibrous material, which provides a high volume flow of resin distributed in a timely manner in the mold.
1. A flow medium for distributing a fluid comprising at least one flow channel and at least one layer of fibrous material, wherein the at least one flow channel is spatially confined in one layer of the at least one layer of fibrous material, wherein the one layer of fibrous material is a three-dimensional entangled mat of extruded filaments in which the extruded filaments are thermally bonded at their crossing points, and wherein the entangled mat of extruded filaments has a void volume of at least 50 vol. %, and wherein the extruded filaments have a thickness in a range of 0.25 mm to 1.2 mm.
2. The flow medium according to claim 1 wherein the at least one layer of fibrous material has two main surfaces, defined by the length and width of the flow medium, wherein the two main surfaces are oriented plane parallel to each other.
3. The flow medium according to claim 1 wherein the at least one flow channel is a porous flow channel.
4. The flow medium according to claim 3 wherein the at least one porous flow channel is a perforated tube.
5. The flow medium according to claim 3 wherein the at least one porous flow channel is a spiral tube.
6. The flow medium according to claim 1 wherein the at least one flow channel has non-porous wall(s).
7. The flow medium according to claim 1 wherein the flow channel has a cross sectional area in the range of 0.5 to 250 mm 2 .
8. The flow medium according to claim 1 wherein the three-dimensional entangled mat of extruded filaments is shaped in a three-dimensional form comprising hills and valleys, hemispheres, positive and/or negative cuspates, cups and/or waffles, pyramids, U-grooves and/or V-grooves.
9. The flow medium according to claim 1 wherein the flow medium has a thickness of 1 to 20 mm.
10. The flow medium according to claim 1 wherein the flow medium comprises one or more additional layers, each of the additional layers being a film or a layer of fibrous material.
11. The flow medium according to claim 1 wherein the flow medium is used in vacuum assisted resin transfer molding processes.
12. The flow medium according to claim 1 wherein the flow medium is in an irrigation system.
13. The flow medium according to claim 1 wherein the flow medium is in a heating or cooling system.
14. The flow medium according to claim 1 wherein the flow channel has a cross sectional area in the range of 10 to 175 mm 2 .
15. The flow medium according to claim 1 wherein the flow channel has a cross sectional area in the range of 75 to 150 mm 2 .
16. The flow medium according to claim 1 wherein the three-dimensional entangled mat of extruded filaments has a void volume of at least 85 vol. %.
17. The flow medium according to claim 1 wherein the three-dimensional entangled mat of extruded filaments has a void volume of at least 95 vol. %.
18. The flow medium according to claim 10 wherein the film or the layer of fibrous material of each of the additional layers is a woven, a two-dimensional grid or scrim, a nonwoven or a three-dimensional entangled mat of extruded filaments.