Abstract: An electronic mixed water preparation device comprises a compact flush-mounted unit for electronically controlling mixed water in private households. Previously, such methods could only be implemented in an industrial environment or in combination with additional devices. The compact unit comprises an electronic controller and a step motor which acts upon a mechanical actuator. The preparation of mixed water can be exclusively carried out in conjunction with a temperature sensor whose measuring values are used to detect throughflow and excess temperature, in addition to actual temperature values.

Abstract: We present the results of experimental study of a Couette–Taylor system with superimposed axial flow and an upper free surface, in the high Taylor number regime. At large Taylor numbers, when the rotational speed of the inner cylinder increases, bubbles created near the free surface are distributed throughout the test section and permit the study of the spatial and temporal properties of turbulent flows using visualization techniques. In addition to classic travelling Taylor vortices, intermittent pulses of vortices with higher phase velocities are also observed. These patterns are described in terms of the rotational speed and the intensity of the throughflow.

Abstract: Annular cavities are found inside rotor shafts of turbomachines with an axial or radial throughflow of cooling air. In order to increase efficiency and system reliability, flow and heat transfer phenomena in those cavities have to be investigated in order to minimize thermal load. For research purposes an experimental rig is set up.This paper focuses on flow visualisation using a laser light sheet technique in a heated rotating cavity which is axially flown through by cooling air. Flow phenomena are observed by a rotating telemetric video camera which shows smoke flowing through the light sheet area located in the axial midplane. The visualisation procedure is described and the first results are pointed out. Additionally, heat transfer measurement across the wall is shown.Copyright © 2000 by ASME

Abstract: This article reports on heat transfer measurements made on a rotating test rig representing the internal disc-cone cavity of a gas turbine high-pressure (H.P.) compressor stack. Tests were carried out for a range of flow rates and rotational speeds at engine representative nondimensional conditions. The rig also had a central drive shaft, which could rotate in the same direction as the discs, contrarotate relative to the discs, or remain static. Measurements of heat transfer were obtained from a conduction solution method using measured surface temperatures as boundary conditions. Results from the outer surface of the cone are in reasonable agreement with theoretical predictions for the heat transfer from a free cone in turbulent flow. The heat transfer measurements from the inner surface of the cone reveal two regimes of heat transfer: one governed by rotation, the other by action of the throughflow. In the rotationally dominated regime, the heat transfer from the inner surface of the cone is higher for a co-rotating shaft than for either a static or contra-rotating shaft. In the throughflow-dominated regime the heat transfer shows little consistent dependence on the direction of shaft rotation. Tests carried out at different values of surface-to-fluid temperature difference add support to the hypothesis that in the rotationally dominated regime the heat transfer occurs through a process of free convection, where the buoyancy force is induced by rotation. The heat transfer from the disc is significantly lower than that from the inner surface of the cone and more or less insensitive to the sense of shaft rotation. The disc average Nusselt numbers show similar behavior to those from the inner surface of the cone and suggest that the disc heat transfer too is governed either by rotationally induced buoyancy or by the axial throughflow.

Abstract: The throughflow and internal heat generation effects on the onset of convection in an infinite horizontal fluid layer are investigated. The boundaries are considered to be rigid (however permeable) and perfectly conducting. The resulting eigenvalue problem is solved by using the Galerkin method, and the effects of various parameters in the stability results are analyzed. The results indicate that the stability of the system is significantly affected by both throughflow and internal heat generation in the fluid layer. The Prandtl number comes into play due to the presence of throughflow and it has a profound effect on the stability of the system. It is found that, in the presence of internal heating, throughflow in one direction supresses convection while throughflow in the other direction encourages it.

Abstract: The correlation between long-term mean heat content and dynamic height is used to estimate the dynamic heights from the temperature profiles of the Indian Ocean. Significant correlation is obtained for the whole Indian Ocean, except the northern part of the Arabian Sea and the Indonesian throughflow region. From the estimated dynamic heights, bimonthly means were computed, and maps were prepared to infer the circulation. The North Equatorial Current, South Equatorial Current, Equatorial Counter Current and the South Indian Ocean Current are clearly distinguished in the maps. Strong Indonesian throughflow is evident during July–August. The seasonal change of the Leeuwin Current off western Australia can also be observed in the dynamic height distribution. The equatorial Kelvin wave and the reflected Rossby waves at low latitudes can be identified in the time-latitude section of the steric height. An annual signal of a Rossby wave is obtained along 12°S.

Abstract: The element has a resistive profile body with a positive temperature coefficient, essentially constant profile in the flow direction and electrode coatings for passing heating current through the body walls essentially perpendicularly to the flow. The walls are of essentially constant thickness corresponding to the current path. Heating ribs with electrode coatings protrude into the throughflow channel, preferably at regular intervals. The element has a profile body (1) of resistive material with a positive temperature coefficient, an essentially constant profile in the flow direction and electrode coatings (4.1,4.2) for passing a heating current through the walls of the profile body essentially perpendicularly to the flow direction. The walls are of essentially constant thickness corresponding to the current path. Heating ribs (2) with electrode coatings protrude into the throughflow channel (3), preferably at regular intervals.

Abstract: Dynamics and structure of spatially localized convective perturbations in binary fluid layers heated from below and the effect of a plane horizontal Poiseuille throughflow on them are investigated. Fronts and pulse-like wave packets formed out of the three relevant perturbations-two oscillatory ones and a stationary one-are analyzed after evaluating the appropriate saddle points of the three respective dispersion relations of the linear field equations over the complex wave number plane. Front and pulse properties are elucidated in quantitative detail as a function of small throughflow Reynolds numbers for different Soret coupling strengths psi including the pure fluid limit psi=0 in comparison with the appropriate Ginzburg-Landau amplitude equation approximations. Furthermore, small amplitude pulses and fronts obtained from solving the full nonlinear field equations numerically are presented to check and compare with the linear results.

Abstract: Water from the western Pacific flows through the Indonesian Seas following different pathways and is modified by various processes to form the uniquely characterized isohaline Banda Sea Water. The processes contributing to the isohaline structure are studied using data from three ARLINDO cruises in 1993, 1994, and 1996. An inverse-model analysis using salinity and CFC-11 data is applied to a vertical section along the main path of flow, from the Makassar Strait to the Flores Sea and Banda Sea. The model reproduces the seasonal and interannual variability of the throughflow and shows reversals of flow in the vertical structure. The model solutions suggest strong baroclinic flows during the southeast monsoon of 1993 and 1996 and a small, more barotropic flow during the northwest monsoon of 1994. The isohaline structure can be accounted for by isopycnal mixing of different source waters and by vertical exchanges, which are significant in this region. A downward flux equivalent to a downwelling velocity of 5 × 10 -7 m/s is estimated for the section. The total balance also suggests that seasonally and possibly interannually variable backflushing of water from the Banda Sea into the Straits contribute to the isohaline structure of Banda Sea water.

Abstract: The circulation of the Indian Ocean in the Hadley Centre Climate Model is characterized by a very strong Indonesian Throughflow of O(24 Sv) compared with observational estimates of O(10 Sv) and very weak deep inflow across 32°S compared with observational estimates. The model throughflow has an upper core and a lower core of approximately equal magnitudes. We examine the driving terms for the throughflow and find that the upper core is driven by the wind stress curl and the lower core is driven by bottom pressure torques. The heat gained by the Indian Ocean from the atmosphere is approximately zero in the model, which is at odds with the observational estimates, which indicate a net heating of the Indian Ocean of between 0.4 and 1.2 PW. We hypothesize that the small heat flux is a direct consequence of the large throughflow and weak overturning. Two sensitivity experiments with different throughflows are described. We find that the magnitude of the deep overturning in the coupled model is strongly related to the magnitude of the lower core of the throughflow. The deep overturning increases from 3 to 9 Sv, as the magnitude of the lower core is reduced from 12 to 0 Sv. We find that the sensitivity of the heat gain of the Indian Ocean to the magnitude of the throughflow is O(0.005 PW) per sverdrup. This weak sensitivity may be due to the fact that the changes in the throughflow in the sensitivity experiments take place in the lower (colder) core.

Abstract: A high resolution, regional, non-linear, barotropic ocean model (2D POM) was used to show that a pressure difference between the Pacific and Indian Ocean does not significantly influence the total transport of the Indonesian throughflow.

Abstract: The addition of cooling fluid into the main flow affects the aerodynamic performance of the blading and causes changes of the overall flow capacity and efficiency of a turbine. Computing systems which consider all those effects are necessary for the performance prediction of cooled multistage turbines. The throughflow method presented here is based on the finite element method and includes models for the radial distribution of losses, for the spanwise mixing and for different cooling configurations, e.g. convection cooling with trailing edge outlet and film cooling. The reliability of the method is verified by comparisons with experimental data of a 1.5 stage cold air turbine with nitrogen ejection in front of the first stator. Because the coolant is ejected at different radii in order to observe the flow path, the radial mixing process is of special importance for this test case. Due to the reliable models used in the throughflow method the mixing between main flow and coolant at the ejection locus and the radial mixing process downstream is well predicted.Copyright © 2000 by ASME

Abstract: A throughflow time-marching finite-volume solver, capable of computing viscous transonic multistage compressor flows with embedded shocks, is presented. The behavior of the blade model, based on the blade mean surface flow tangency condition, was investigated for transonic flows. The captured passage shock was found to be treated as a normal blade passage shock by the blade model. The choke mass flow prediction was improved by introducing an alternative blade blockage based on a streamtube approach. Two techniques for solving the numerical problems associated with the leading edge singularity in case of incidence are described. Effects due to deviation, secondary losses, endwall skin friction and spanwise mixing are also modeled. The various models, once calibrated on two single stage transonic compressor test cases, were validated on a three-stage transonic model fan. The calculated speed-line performance agreed well with the measured data. To assess the three-dimensional flow departure from the axisymmetry assumption, the tangential spatial perturbation stress terms were derived from the circumferential average of 3D computations of the Nasa 67 transonic rotor. A meridional picture of each of the averaged stresses is given for two flow conditions, near-stall and near-peak efficiency. With the source terms derived from the near-peak efficiency 3D solution, several throughflow computations were carried out to study the influence on the meridional flow of the averaged viscous stresses and of each spatial perturbation stress. The spatial stresses were found to be the main contributors to the blade passage losses and the spanwise mixing phenomenon in comparison with the viscous stresses. The relative importance study of each perturbation term showed that a few of them exert a significant influence on flow angles and losses in the tip region. In order to compare the throughflow multistage calculations with their 3D counterparts, a multistage 3D computation of the three-stage fan speed-line was performed using a mixing plane approach. The tangential average of the near-peak efficiency fan 3D solution was compared with a throughflow computation regarding entropy increase and flow angles. The throughflow solution was found to yield an overprediction of shock losses in the first rotor because of a leading edge singularity related problem. Two alternatives to the original blade model were studied. The first is based on a prescribed blade loading distribution which yields a meridional flow similar to the tangentially averaged 3D flow but requires additional shock loss correlations. The second is based on applying the usual blade model for most of the blade chord, except for the first 20 % where a distributed blade loading is applied. This model proved to alleviate the leading edge singularity problem and still enables one to capture shocks and compute choked-flow conditions. An unsteady calculation of the IGV and first stage of the transonic model fan was carried out in order to assess the reliability of the steady 3D multistage computational method. The steady and time-averaged flows were compared and the differences found were interpreted in terms of the so-called deterministic stresses. An evaluation of the spatial and temporal correlations, in accordance with the deterministic stress tensor decomposition of Adamczyk, was carried out for the rotor flow.

Abstract: The arrangement has at least one regulated coolant circuit in which at least some machine parts (1) are included with their waste heat. Regulation of the coolant circuit is conducted using a throughflow regulation approach. The flow of coolant is increased when its temp. increases and is reduced when the temp. drops.

Abstract: The axial f low turbomachinery throughflow equation states that radial gradients of rothalpy, entropy and moment of momentum affect the conservation of tangential vorticity. The streamline throughflow method (STFM) transforms this equation, expressed in terms of stream function in a radial-axial co-ordinate system, to an equation for streamline radial position in a stream function-axial co-ordinate system. The paper assesses the accuracy and efficiency of the STFM relative to the streamline curvature method (SCM) by comparing streamline positions and velocity profiles to analytical results. Test cases include flow through a single actuator disc, flow through twin actuator discs using a coarse computational grid, compressible f lows through an almost choked nozzle, through single and twin actuator discs, and swirling f low using sloped stations. Results f rom the STFM and SCM agreed about equally well with analytical solutions for the same number of streamlines. The STFM, however, was much more tolerant of distorted computational grids and used an order of magnitude less computer time to converge. The test cases show that the STFM is suitable for annuli with large variations in hub and tip radius, for highly swirling and compressible flow, and is more robust and converges faster than the SCM. To demonstrate the practical applicability of the STFM a multistage compressor was simulated and STFM results compared with experiment. Nomenclature STFM streamline throughflow Τ absolute temperature a = tangential velocity factor for actuator W relative velocity disc flow; sonic velocity x, y orthogonal co-ordinate system ADT = actuator disc theory components b = tangential velocity factor for actuator ζ = axial co-ordinate disc flow; y specific heat ratio = unblocked fraction P density C = absolute velocity ψ stream function CP = specific heat at constant pressure F = force Subscripts I = rothalpy b body h = enthalpy in inlet LHS = left hand side out = outlet Μ = Mach number 0 stagnation property MTFM = matrix throughflow method r = radial component Ρ = pressure ζ = axial component r = radial co-ordinate, radial position of θ tangential component streamline R = gas constant RHS = right hand side Introduction s = entropy S = source term During the last decade the main emphasis in SCM = streamline curvature turbomachir· ;ry flow analysis has been on

Abstract: The dishwasher has pipeline system for a liquid, e.g. water, washing solution. or similar containing. a riser line leading out of the washing chamber and a throughflow heater (1) with a tubular housing for heating the liquid using an internal heating element. The riser pipe incorporates the throughflow heater.

Abstract: This work deals with the generalization of the spherical Couette flow from a closed flow into an open flow system. A superimposed throughflow in meridional direction leads to novel flow structures and stability behaviour. A analytical solution for the superposition of the spherical Couette and the source-sink flow is given for the creeping flow. Numerical simulations for steady and time-dependent rotationally symmetric solutions are presented for a large Reynolds number range. These solutions represents the non-uniqueness of the supercritical spherical Couette flows. Their symmetry with respect to the equator and time-behaviour depends strongly on the throughflow Reynolds number. The experiments show the rich variety of supercritical solutions depending on the rotation and throughflow parameters. Rotationally symmetric vortices and spiral vortices are realized in steady and time-dependent form. For the pure source-sink flow the instabilities are formed like banana shaped structures. The existence regions and transitions between the different modes of flow are presented in maps. For the rotationally symmetric states there is a good agreement between theory and experiments.

Abstract: A test fluid pipe(12) for connecting to the subject connection(4) determines the test value, namely a fluid pressure, volume flow or suchlike, and means are provided for throughflow testing by means of suction comprising a test pressure source for connecting to the test pipe which has a very small nominal flow passage area. At least one sensor(26,27) is provided for recording at least one test value, and the test pipe is a suction line, and the test pressure source a vacuum source(17). An Independent claim is included for a procedure for throughflow testing of a fuel tank connection in which the connection is subjected to a flow of test fluid by suction.

Abstract: The water circulation channel has at least one ramp (6a,6b) for entering and exiting into and out of the channel, whereby the throughflow and position can be altered wrt. height and inclination. The ramp has adjustable flaps that can be pivoted into open and closed positions, whereby the water flow in the channel can be rapidly regulated with the pump running to achieve an approximately horizontal flow with minimal flow losses.

Abstract: Paleoproductivity in the Timor Trough appears to be inversely proportional to the strength of the Indonesian Throughflow. Today, productivity in the area is inhibited by the narrow band of low-salinity surface water that moves through the Indonesian Archipelago and spreads out over the equatorial portions of the eastern Indian Ocean. During the Last Glacial Maximum, however, the reduction or absence of this low-salinity “cap” would have enhanced the possibility of upwelling and higher productivity in the region. Our results indicate that at this time, productivity was enhanced, the surface waters were being depleted of CO2 and relative nitrate utilization was low. This suggests that the thermocline was shallow and that upwelled, nutrient-rich water was present.

Abstract: This study examined the spatial and temporal variability of throughflow in a shallow forest oil in terms of the controls exerted by topography, soil properties and the shape of the water table. Hillslope outflow was measured at nine troughs installed at a road cut, and hydraulic head was measured at 37 piezometers installed to the confining till surface at the base of the soil. At the lowest flows, the distribution of throughflow across the hillslope conformed reasonably to the distribution of upslope contributing area computed from the topography of the confining basal till layer. At higher flows, however, the distribution of throughflow shifted, partly as a result of changes in the orientation in flow tubes as the piezometric surface changed. At high flows, surface topography appeared to provide a reasonable proxy for the shape of the water table. Shunting of water through discrete macropores, however, can apparently overwhelm topographic controls on throughflow, at least for slope widths less than about 10 m. Effective hydraulic conductivities computed at the scale of the troughs varied over two orders of magnitude and displayed no consistent relationship with the thickness of the saturated layer. Estimates at the plot scale (c. 10 m hillslope width) were far less variable, and for higher flows displayed an approximately linear relationship with saturated zone thickness. Copyright © 2000 John Wiley & Sons, Ltd.