Abstract: Apparatus and methods are described for use in mixing of fluids or mixing ingredients into fluids by means of a static mixer assembly (i.e. without requiring moving mechanical parts, where fluid flow is used to achieve mixing). The static mixer assembly is a cylindrical tube with three pairs of fins extending inward from the inner wall of the tube. The central fins form a prow pointing upstream, with two pairs of flanking fins arranged to prevent unhindered fluid flow parallel to the central axis of the tube a peripheral region, while allowing unobstructed flow in a central region and extending to a peripheral region near the inner wall opposite the prow. The fins force fluid outwards along the inner walls from the prow towards the unobstructed peripheral region opposite the prow and additionally fluid spills over the inner edges of the fins into the central region. The resulting flow pattern provides excellent mixing with a low ratio of pressure drop to volumetric flow rate across the assembly.

Abstract: Apparatus and methods are described for use in mixing of fluids or mixing ingredients into fluids by means of a static mixer assembly (i.e. without requiring moving mechanical parts, where fluid flow is used to achieve mixing). The static mixer assembly is a cylindrical tube with three pairs of fins extending inward from the inner wall of the tube. The central fins form a prow pointing upstream, with two pairs of flanking fins arranged to prevent unhindered fluid flow parallel to the central axis of the tube a peripheral region, whilst allowing unobstructed flow in a central region and extending to a peripheral region near the inner wall opposite the prow. The fins force fluid outwards along the inner walls from the prow towards the unobstructed peripheral region opposite the prow and additionally fluid spills over the inner edges of the fins into the central region. The resulting flow pattern provides excellent mixing with a low ratio of pressure drop to volumetric flow rate across the assembly.

Abstract: A method and an apparatus are described for use in the irradiation of fluids. The apparatus has an elongate conduit (312) having a central axis (334) and two or more elongate ultraviolet radiation sources (114) extending along the interior of the conduit for irradiation of the fluid within the conduit. An array of static mixer elements (300) is located within the conduit, and the two or more elongate ultraviolet radiation sources (114) are arranged to extend through apertures in deflection surfaces of the static mixer elements making up the array (300). The apparatus and method allows for reliable and uniform ultraviolet irradiation of fluids of low UV transmissivity, such as turbid fluids, particularly for ultraviolet disinfection of such fluids. Wipers may be fitted to the static mixer elements to enable relative movement between the static mixer elements and the surfaces of the elongate ultraviolet radiation sources to clean the surfaces of the sources without need to dismantle the apparatus.

Abstract: A method and an apparatus are described for use in the irradiation of fluids. The apparatus has an elongate conduit (312) having a central axis (334) and two or more elongate ultraviolet radiation sources (114) extending along the interior of the conduit for irradiation of the fluid within the conduit. An array of static mixer elements (300) is located within the conduit, and the two or more elongate ultraviolet radiation sources (114) are arranged to extend through apertures in deflection surfaces of the static mixer elements making up the array (300). The apparatus and method allows for reliable and uniform ultraviolet irradiation of fluids of low UV transmissivity, such as turbid fluids, particularly for ultraviolet disinfection of such fluids. Wipers may be fitted to the static mixer elements to enable relative movement between the static mixer elements and the surfaces of the elongate ultraviolet radiation sources to clean the surfaces of the sources without need to dismantle the apparatus.

Abstract: A static mixer comprising a group of deflector elements distributed within a conduit through which a fluid flows in a direction generally parallel to an axis of the conduit. Each deflector element defines a surface which is inclined to the conduit axis such that fluid is deflected by the surface in a direction transverse to that axis. The deflector elements are positioned so as to generate an asymmetric vortex flow such that the intensities of adjacent vortices are different. The deflection elements may be in the form of, for example, asymmetric pairs of tabs, for example spaced apart pairs of tabs of different lengths. The angle of inclination of the tabs to the conduit axis may be adjustable.