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A method is presented for the determination of secondary flow fields in three practical examples. In one, the flow is laminar and the other two turbulent. The latter were analysed using a one‐equation or two‐equation model of turbulence in conjunction with the equations of motion. Methods of improving the boundary condition for secondary flow prediction by introducing a ‘slip’ condition at near wall locations are referred to, and its effect demonstrated. Finally, a fluid film of extremely high aspect ratio and in laminar motion was investigated and the existence of recirculatory flow pockets predicted.

A finite element based numerical model is employed to obtain isothermal and heat transfer predictions for the case of turbulent flow with a decaying swirl component in a stationary circular pipe. An assessment is made on the quality of predictions based on the choice of turbulence modelling technique adopted to close the governing equations. In the present work the one‐equation, two‐equation and algebraic Reynolds stress turbulence models are employed. For the confined flow problem investigated, accurate prediction of the near‐wall conditions is essential. This is particularly the case for confined swirling flow where the variation of variables near the wall is often somewhat greater than encountered in pure axial flow. A finite element based near‐wall model is employed as an alternative to conventional techniques such as the use of the standard logarithmic functions. Of significance is the fact that flow predictions based on the use of the unidimensional finite element techniques are closer to experiment compared to the wall function based solutions for a given turbulence model. As expected, improvements in the flow predictions directly contribute to improved simulation of the thermal aspects of the problem.

An inherent problem when analysing confined turbulent flows, using a numerical approach, is mapping within the conventionally termed ‘near wall zone’. In order to accommodate the rapid variations in both velocities and turbulent kinetic energies the region would, if conventional techniques are employed, require an extremely fine spatial subdivision.

A combined experimental and numerical investigation into the fluid flow and heat transfer processes that take place in the spray deposition of tubular preforms is presented. The work is concerned principally with impingement mechanisms at jet diameter to target distances that are large in comparison with previous reported studies. The experimental investigation required the design of a novel heat transfer meter that was capable of resolving the heat transfer coefficient within 2.5 per cent. The experiments gave a new correlation for stagnation heat transfer, similar in form to correlations that have been published for small jet diameter to target distance values. The experiments also showed the presence of skewing of the heat transfer coefficient in the deposition zone due to its tapered nature. A finite volume based model of the deposition chamber was developed and run to compare with the experimental data. This model was found to yield trends similar to those measured experimentally, thus confirming its qualitative capability. However the absolute values of heat transfer coefficient that were computed were significantly lower than measured values. This points to the requirement to consider alternative computing schemes and to investigate the methods of representing the heat transfer mechanisms at the physical boundaries, particularly at the preform surface.

A finite element method based investigation is carried out for the determination of three‐dimensional turbulent flow structures and heat transfer rates of cooling ducts within turbine blades which rotate about an axis orthogonal to their own axis of symmetry. The effects of geometrical configurations, Coriolis forces and coolant inertias on the hydrodynamic and thermal characteristics have been systematically predicted and compared with experimental measurements.

A method is presented for the determination of heat transfer rates in cylindrical cooling ducts which rotate about an axis orthogonal to its own axis of symmetry. The equations of motion and energy are solved in conjunction with the two equation model of turbulence (k—ε) using the finite element method. The importance of employing consistent velocity and turbulence quantities is demonstrated; the former condition is particularly relevant with respect to induced secondary flows. It was also found that comparatively minor mesh refinement had a significant effect on both the flow and the increase in heat transfer rates over those obtained for the non‐rotating case.

Finite element based solution techniques have been developed to replace the conventional ‘wall functions’ in the ‘near wall zone’ of general confined turbulent flows. The technique is validated by application to the turbulent flow and associated heat transfer within a square/rectangular cross‐sectioned duct rotating about an axis orthogonal to its longitudinal axis. The predicted results are compared with those from experimental measurements and excellent agreement is obtained when using the advocated methodology.

The purpose of this paper is to study theoretically the combined influence of journal misalignment and wear on the performance of a hole‐entry hybrid journal bearing system. The bearing is assumed to be operating in a turbulent regime.

The modified Reynolds equation based on Constantinescu lubrication theory has been solved by using finite element method together with orifice and capillary restrictors flow equations as a constrain together with appropriate boundary conditions.

It has been observed that for a symmetric hole‐entry journal bearing configuration the value of h¯_min is more for the bearing compensated by orifice restrictor as compared to capillary restrictor when bearing operates in turbulent regime under worn/unworn conditions. From the point of view of stability threshold speed ω¯_th, the reduction in the value of ω¯_th for capillary compensated bearing is around −3.89 percent whereas for orifice compensated bearing it is −7.85 percent when misaligned worn bearing is operating in turbulent regime.

The present work is original of its kind, in case of misaligned hole‐entry worn journal bearing. The results are quite useful for the bearing designer.

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.

Deals with the flow reversal in a buoyancy‐opposed rotating duct that causes heat transfer deterioration. An active technique of trailing‐wall transpiration is adopted to check whether it can avoid the flow separation and subsequently improves the heat transfer deterioration. Finite‐difference method is employed to solve the three‐dimensional Navier‐Stokes equations and the energy equation. Periodic conditions are used between the entrance and exit of a typical two‐pass duct for the closure of the elliptic problem. The predicted results reveal that fluid withdrawal through the trailing wall can avoid the flow separation from the leading wall of the radial‐outward duct (ROD) and thus eliminate local hot spots. In addition, the trailing‐wall suction not only increases the peripherally averaged heat transfer but also reduces the friction loss in the ROD. In the radial‐inward duct (RID), both the peripherally averaged heat transfer and peripherally averaged friction factor are augmented by trailing‐wall injection and are degraded by the trailing‐wall suction.