Variable Pitch Fans (GB 2485634 B)
Geoff Sheard & Andreas Rhoden
The present invention relates to an axial air movement fan having a plurality of variable-pitch-in-motion blades. Each blade extends radially from a hub that rotates about the fan’s main axis. A bearing located within the hub supports each blade that enables it to pivot about its radial axis. The hub incorporates a mechanism to pivot the blades simultaneously, thus varying the pitch of all blades in unison.
Axial Air Movement Fans (GB 2486470 A)
Geoff Sheard, Alain Godichon & D. Revillot
The invention relates to axial fans comprising a hub mounted for rotation about an axis. The fan comprises a plurality of elongated fan blades, only one of which is shown as reference, equidistantly disposed about the hub’s periphery and secured so as to extend in a generally radial direction. The blade consists of an elongated member extending generally radially and is secured at its root to the hub at a slight angle to the hub’s plane of rotation. The fan has in its cross-section a major and a minor axis. It also has a radially extending longitudinal main axis. Each blade includes at least one damping mass secured to the fan in such a way as to enable the mass to oscillate relative to the blade in response to the blade’s oscillatory flexing, thereby damping the blade’s flexing.
A Method of Detecting and Controlling Stall in an Axial Fan (GB 2468571 B)
Geoff Sheard, Alessandro Corsini & Stefano Bianchi
The present invention provides a stall-detection method based on measurements of the sound that emanates from the flow through a fan. It prepares a visual representation of the sound. Then, one can compare the visual representation with fixed visual representations derived from a plurality of tests that are representative of the fan’s performance under a range of operating conditions. One may select the fixed visual representation that most closely matches the said sound’s visual representation and derive a control signal from the selected fixed visual representation.
A Meridional Fan (GB 2452104 B)
Geoff Sheard, Alessandro Corsini & Franco Rispoli
The invention seeks to provide improved blade-tip end-plate geometry. The improved geometry both increases fan efficiency and simultaneously reduces the fan’s far-field noise. This improvement is achieved by managing the intensity of the flow-field features associated with the blade tip-to-casing leakage flow. The primary flow-field feature associated with the leakage flow is a leakage vortex, which constitutes both an aerodynamic loss mechanism that reduces fan efficiency and a noise source that increases fan far-field noise.
Capacitive Gap Measurement Device (GB 2325305 B)
In many fields, and especially during the development of gas turbines, there is a need for a gap measurement sensor that is able to function at high temperatures, for example in the order of 1000°C or more. Improvement of the thermodynamic efficiency of a gas turbine may be achived with a higher turbine entry temperature. The inventor is therefore conducting research to increase gap measurement sensor working temperature, for example to 1200°C or higher. In such high temperature environments it is not possible to employ sensors that rely on the permanent magnetism of materials. It is important to ensure that all materials used to produce the sensor can withstand the high temperatures involved. For this reason, the author proposed capacitance sensors for use in turbines.
Gap Measurement Device (US5760593 A)
Geoff Sheard & David Charles Lawrence
This invention provides a device for capacitively measuring the distance to an object, which comprises an electrode that will couple capacitively with the object, a shield that surrounds the electrode and is electrically isolated from the electrode by means of insulation, and a layer of insulation that surrounds the shield, wherein the insulation between the electrode and the shield, and the insulation that surrounds the shield, are formed by deposition.
This invention further provides a method for measuring the distance to a solid object, which comprises forming an electrode that will capacitively couple with the object, depositing a layer of insulation over at least part of the electrode so that the insulation surrounds the electrode, depositing a layer of metal over the insulation to form a shield, and depositing a second layer of insulation over the shield.