Abstract: A civil engineering damper for damping civil engineered structures comprising a damper housing including two dynamic fluid chambers within a piston cylinder and two static fluid chambers straddling the dynamic fluid chambers along an axis of the housing a piston mounted for reciprocation along the axis of the damper housing. A piston web portion divides the piston cylinder into the two dynamic fluid chamber. A restricted passageway through the piston web portion includes an orifice that provides a resistance to fluid flow between the dynamic fluid chambers. The damper also includes regulated passageways between adjacent dynamic and static fluid chambers valved to allow a flow of fluid from the static fluid chambers to the dynamic fluid chambers and check flows of fluid from the dynamic fluid chambers to the static fluid chambers.

Abstract: A damper for a structural tower having a space frame construction for high elevation and heavy load applications is disclosed, with particular application directed to wind turbines. The structural tower includes one or more dampers for damping resonant vibrations or vibrations generated by non-periodic wind gusts or sustained high wind speeds. The wind tower damper includes a fluid damper comprising a housing, elastomeric chamber, piston and damping fluid, wherein relative motion between the first and second structural members drive the fluid moving piston to pump the fluid and thereby dissipate unwanted motion in the tower.

Abstract: A rotary impeller assembly is for a fluid machine and includes a support member having an outer surface and blades connected to the support member. Each blade includes first and second integral portions, the blade first portion having a first thickness and being spaced from the base surface and the blade second portion is disposed against the support member outer surface and has a second thickness. The second thickness is substantially greater than the first thickness such that the blade has greater stiffness proximal to the support and a lesser stiffness generally distal from the support. Preferably, the blades are connected with the support welds between each blade sidewall and the support member. Further, each blade first portion is sized such that the blade first thickness is maintained in a significant area of the blade spaced from the weld(s) so as to allow blade flexure away from the weld.

Abstract: A method of welding and an assembly formed thereby, according to which a first member is formed with a first thickness and a second thickness greater than the first thickness. The first member is welded to a second member and a toe is formed in at least one wall of the first member in that portion of the first member having the increased thickness.