Papers by Author: Miltiadis Kourmpetis

Abstract: Cost effective and reliable operation of a power station plant and achieving low carbon dioxide emissions can be very dependent on maintenance activities. Planning maintenance to minimise the down-time of the plant is a key cost factor. It is important to have the latest data as to the age and state of the components and parts at the time of plant shut down. Indeed, deciding on the best time to shut down the plant for maintenance can depend upon trends in these data. For steam pipes, the required ageing information is the creep strain rate. These creep strain data obtained at shut down provide key information as to the needed replacement of pipes to maintain reliable plant operation. This paper presents the E.ON UK ARCMAC creep strain measurement systems that are being further developed by Imperial College London with the use of DIC and other techniques.

Abstract: Optical strain measurement techniques have been extensively developed in recent years in order to cope in various environments. Power stations and wind turbine blades can provide challenging environments for the use of a measurement technique. There are, however, many installation problems to be overcome. For example, there is the need to have regard for the hostile environment in steam generating plant and the demanding conditions to which wind turbine blades are subjected. Ideally the outputs from individual sensors would be used for continuous remote monitoring. However, measurements can also be useful each time the plant is shut down during a plant outage; which would be used to complement data from existing proven rugged monitoring methods. This paper addresses the monitoring of pressurized steam pipes as to their micro-strain growth related to time in service. This paper presents the progress made in the developing of a ruggedised digital speckle ‘sensor’ and associated image capture system. The effect of subsurface defects in the strain distribution is examined.