Part I of this paper described how the HP turbine model rig of the Rolls-Royce Trent 500 was redesigned by applying non-axisymmetric end walls to both the vane and blade passages, whilst leaving the turbine operating point and overall flow conditions unaltered. This paper describes the results obtained from testing of the model rig and compares them with those obtained for the datum design (with conventional axisymmetric end walls). Measured improvements in the turbine efficiency are shown to be in line with those expected from the previous linear cascade research at Durham University, see Harvey et al. [1] and Hartland et al. [2]. These improvements are observed at both design and off-design conditions. Hot wire traverses taken at the exit of the rotor show, unexpectedly, that the end wall profiling has caused changes across the whole of the turbine flow field. This result is discussed making reference to a preliminary 3-D CFD analysis. It is concluded that the design methodology described in part I of this paper has been validated, and that non-axisymmetric end wall profiling is now a major new tool for the reduction of secondary loss in turbines (and potentially all axial flow turbomachinery). Further work, though, is needed to fully understand the stage (and multistage) effects of end wall profiling.

Thrust in Electrical Submersible Pumps (ESPs) is a very important factor that affects pumps' performance. Thrust forces in pumps can increase the friction losses and reduce the overall pump efficiency and lifetime. Pump designers have to design pumps to handle thrust generated in the operating range whether by adding up-thrust protection, down-thrust protection, or sometimes both kinds of protections if the operating range includes both up and down thrust.Hydraulic thrust mainly depends on the hydrodynamic forces generated inside ESPs. These hydrodynamic forces depend on many factors like blade loading, seal geometries, seal diameters, seal engagement, and balance holes location and sizes. Not only is the thrust magnitude important to predict, but also the shape of the thrust curve plays an important role in defining the operating range. If the thrust curve is flat, then this means a wider operating range for the pump. Currently, no model is available to predict or design for thrust curve. Engineers use an iterative process of manufacturing and testing trying to reach the optimum seal configuration and balance holes geometry for better thrust and pump performance.In this paper, a detailed CFD model of a mixed flow multistage ESP is presented including all seal elements and balance holes to be able to predict hydraulic thrust. Thrust curve is predicted for the first time using CFD analysis. Different seal geometries and balance holes configuration is also modeled to study the effect of geometry change on thrust curve. The model is validated using experimental test results. Also, other design parameters like the shape of the head curve, pump efficiency, and gas handling capability were controlled early in the design phase using CFD analysis.

In this paper, we consider the filtering problem of an optical parametric oscillator (OPO). The OPO pump power may fluctuate due to environmental disturbances, resulting in uncertainty in the system modeling. Thus, both the state and the unknown parameter may need to be estimated simultaneously. We formulate this problem using a state-space representation of the OPO dynamics. Under the assumption of Gaussianity and proper constraints, the dual Kalman filter method and the joint extended Kalman filter method are employed to simultaneously estimate the system state and the pump power. Numerical examples demonstrate the effectiveness of the proposed algorithms.

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Steam-assisted gravity drainage (SAGD) and other thermal recovery applications require electrical submersible pump (ESP) equipment which can withstand extremely harsh oilfield environments with well conditions typically including high gas, sand, and scale concentrations in addition to the extreme temperatures and temperature cycles generated in the process. Thermal recovery pump construction specifications were developed as part of a new tiered product line covering deployment of equipment in wells with bottom hole temperatures (BHT) as high as 250°C. Special construction considerations were implemented for stage compression, thrust handling, bearing design and materials of construction. The new pump technology combines high temperature and abrasive handling features to extend product life and provide consistent reliability in thermal recovery applications. Enhanced temperature tolerance is achieved through reduced thermal stresses on internal components leading to better reliability and increased run life. This next generation of thermal recovery pumps has been extensively field validated with systems utilizing the new technology currently installed and operating in over 400 wells.