The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 08, 2002
Filed:
Dec. 20, 2001
Donald T. Knauss, Severna Park, MD (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A forced-recirculation boiler (FRB) type of heat-recovery steam generator is applied to a ship-propulsion application of the recuperative dual-fluid engine. Such boilers generally include an economizer, evaporator and superheater, and incorporate a steam drum for controlling the flow of water-steam mixture through the evaporator. By altering the flow system of the FRB, the stability and integrity of the boiler are maintained by simultaneously providing, under any predetermined off-design, gas-side flow conditions, means for (1) limiting the gas-side cold corrosion of said boiler tubes through tube-wall temperature control, and (2) introducing a controllable sensible component into the heat load of said evaporator, thereby enabling, for any predetermined off-design steam rate, stable evaporator operation at a predetermined design steam quality. One embodiment of the invention is achieved by adding to the flow circuit of the economizer a recirculation loop that enables, through diversion of the water flows within the loop, the conditioning of the flows to both the economizer and the steam drum. Simulation of the operation of the flow-system invention along the power-profile curve of the engine has demonstrated the efficacy of the flow-system in enabling, at any particular point on the power-profile curve, the predetermined steam rate needed for optimum performance of the engine.