Measurement and Calculation of Nozzle Guide Vane End Wall Heat Transfer

1999 ◽  
Vol 121 (2) ◽  
pp. 184-190 ◽  
Author(s):  
N. W. Harvey ◽  
M. G. Rose ◽  
J. Coupland ◽  
T. V. Jones

A three-dimensional steady viscous finite volume pressure correction method for the solution of the Reynolds-averaged Navier–Stokes equations has been used to calculate the heat transfer rates on the end walls of a modern High Pressure Turbine first-stage stator. Surface heat transfer rates have been calculated at three conditions and compared with measurements made on a model of the vane tested in annular cascade in the Isentropic Light Piston Facility at DERA, Pyestock. The NGV Mach numbers, Reynolds numbers, and geometry are fully representative of engine conditions. Design condition data have previously been presented by Harvey and Jones (1990). Off-design data are presented here for the first time. In the areas of highest heat transfer, the calculated heat transfer rates are shown to be within 20 percent of the measured values at all three conditions. Particular emphasis is placed on the use of wall functions in the calculations with which relatively coarse grids (of around 140,000 nodes) can be used to keep computational run times sufficiently low for engine design purposes.

Author(s):  
Neil W. Harvey ◽  
Martin G. Rose ◽  
John Coupland ◽  
Terry Jones

A 3-D steady viscous finite volume pressure correction method for the solution of the Reynolds averaged Navier-Stokes equations has been used to calculate the heat transfer rates on the end walls of a modern High Pressure Turbine first stage stator. Surface heat transfer rates have been calculated at three conditions and compared with measurements made on a model of the vane tested in annular cascade in the Isentropic Light Piston Facility at DERA, Pyestock. The NGV Mach numbers, Reynolds numbers and geometry are fully representative of engine conditions. Design condition data has previously been presented by Harvey and Jones (1990). Off-design data is presented here for the first time. In the areas of highest heat transfer the calculated heat transfer rates are shown to be within 20% of the measured values at all three conditions. Particular emphasis is placed on the use of wall functions in the calculations with which relatively coarse grids (of around 140,000 nodes) can be used to keep computational run times sufficiently low for engine design purposes.


Author(s):  
J. M. Fougères ◽  
R. Helder

Three-dimensional Navier-Stokes calculations have been performed on various geometries in the presence of discrete-hole injection. The quality of the aerodynamic and thermal predictions of the flow is assessed by comparison to experiments. The code used for the calculations is developed at ONERA and has previously been presented by various authors (Billonnet et al., 1992). It solves the unsteady set of three-dimensional Navier-Stokes equations, completed by a mixing-length turbulence model, using a finite volume technique. The multi-domain approach of the code has facilitated the treatment of this type of geometry. The injection holes are discretized on cylindrical subdomains which overlap the mesh of the main flow. Two applications of the code are presented in this paper. First, a calculation was performed on a row of hot jets injected into a flat plate turbulent boundary layer. Secondly, the code was tested on a plane nozzle guide vane grid with multiple injections. Heat transfer rates, temperature and velocity profiles are compared to experimental data.


Author(s):  
Shahrokh Shahpar

A new approach to three-dimensional design of turbomachinery blades is presented. A number of heuristic and gradient based optimisers are used in conjunction with a linear sensitivity analysis tool, FAITH, to re-design a turbine nozzle guide vane. A novel linear approach is used to eliminate the large computational costs usually associated with function evaluations which are essentially solutions to the Navier-Stokes equations. Results are compared with those obtained previously from the inverse design mode of FAITH. With the present approach, it is shown that nonlinear complicated cost functions can be reduced significantly and aerodynamic and geometrical constraints can be handled easily and efficiently.


Author(s):  
N. W. Harvey ◽  
T. V. Jones

Detailed measurements of surface static pressures and heat transfer rates on the aerofoil and hub end wall of an annular nozzle guide vane (in the absence of a downstream rotor) are presented. Heat transfer rates have been measured using thin film gauges in an annular cascade in the Pyestock Isentropic Light Piston Cascade. Test Mach numbers, Reynolds numbers and cascade geometry are fully representative of engine conditions. The results of 3-D calculations of surface Mach number and 2-D calculations of aerofoil heat transfer are presented and compared with the measurements. A new method of calculating end wall heat transfer using the axisymmetric analogue for three-dimensional boundary layers is described in detail. The method uses a 3-D Euler solver to calculate the inviscid surface streamlines along which heat transfer coefficients are calculated. The metric coefficient which describes the lateral convergence or divergence of the streamlines is used to include three-dimensional effects in the calculation. The calculated heat transfer rates compare well with the measured values. Reference is made to surface flow visualization in the interpretation of the results.


Author(s):  
Roberto Maffulli ◽  
Li He

The present work is aimed to examine how the heat transfer coefficient (HTC) and main three-dimensional (3D) passage aerodynamic features may be affected by a nonadiabatic wall temperature condition. A systematic computational study has been first carried out for a 3D nozzle guide vane (NGV) passage. The impacts of wall temperature on the secondary flows, trailing edge shock waves, and the passage flow capacity are discussed, underlining the connection and interactions between the wall temperature and the external aerodynamics of the 3D passage. The local discrepancies in HTC in these 3D flow regions can be as high as 30–40% when comparing low and high temperature ratio cases. The effort is then directed to a new three-point nonlinear correction method. The benefit of the three-point method in reducing errors in HTC is clearly demonstrated. A further study illustrates that the new method also offers much enhanced robustness in the wall heat flux scaling, particularly relevant when the wall thermal condition is also shown to influence the laminar–turbulent transition exhibited by two well-established transition models adopted in the present work.


Mathematics ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 756
Author(s):  
Federico Lluesma-Rodríguez ◽  
Francisco Álcantara-Ávila ◽  
María Jezabel Pérez-Quiles ◽  
Sergio Hoyas

One numerical method was designed to solve the time-dependent, three-dimensional, incompressible Navier–Stokes equations in turbulent thermal channel flows. Its originality lies in the use of several well-known methods to discretize the problem and its parallel nature. Vorticy-Laplacian of velocity formulation has been used, so pressure has been removed from the system. Heat is modeled as a passive scalar. Any other quantity modeled as passive scalar can be very easily studied, including several of them at the same time. These methods have been successfully used for extensive direct numerical simulations of passive thermal flow for several boundary conditions.


1993 ◽  
Vol 115 (2) ◽  
pp. 283-295 ◽  
Author(s):  
W. N. Dawes

This paper describes recent developments to a three-dimensional, unstructured mesh, solution-adaptive Navier–Stokes solver. By adopting a simple, pragmatic but systematic approach to mesh generation, the range of simulations that can be attempted is extended toward arbitrary geometries. The combined benefits of the approach result in a powerful analytical ability. Solutions for a wide range of flows are presented, including a transonic compressor rotor, a centrifugal impeller, a steam turbine nozzle guide vane with casing extraction belt, the internal coolant passage of a radial inflow turbine, and a turbine disk cavity flow.


Author(s):  
Fahua Gu ◽  
Mark R. Anderson

The design of turbomachinery has been focusing on the improvement of the machine efficiency and the reduction of the design cost. This paper presents an integrated design system to create the machine geometry and to predict the machine performance at different levels of approximation, including one-dimensional design and analysis, quasi-three-dimensional-(blade-to-blade, throughflow) and full-three-dimensional-steady-state CFD analysis. One of the most important components, the Reynolds-averaged Navier-Stokes solver, is described in detail. It originated from the Dawes solver with numerous enhancements. They include the use of the low speed pre-conditioned full Navier-Stokes equations, the addition of the Spalart-Allmaras turbulence model and an improvement of wall functions related with the turbulence model. The latest upwind scheme, AUSM, has been implemented too. The Dawes code has been rewritten into a multi-block solver for O, C, and H grids. This paper provides some examples to evaluate the effect of grid topology on the machine performance prediction.


Author(s):  
F. J. Hong ◽  
P. Cheng ◽  
H. Ge ◽  
Teck Joo Goh

In this paper, a numerical simulation is carried to study pressure drop and heat transfer in a fractal tree-like microchannel net heat sink of 10mm×12.5mm×0.5mm in dimensions. The numerical result is obtained by solving three-dimensional Navier-Stokes equations and energy equation, taking into consideration conjugate heat transfer in the microchannel walls. A comparison of fractal tree-like microchannel net heat sink with 6 branch levels to parallel microchannels heat sink, with respect to the pressure drop, thermal resistance and temperature uniformity, was also performed under the condition of the same heat sink dimensions. The results indicates that for a mass flow rate of water less than 0.00175kg/s, the fractal tree-like microchannel is much better than parallel channel heat sink with respect to all of three aspects. Therefore, the fractal tree-like microchannels net heat sink using water as the coolant is promising to be used in the future electronic cooling industry.


Author(s):  
Andrea Arnone ◽  
Roberto Pacciani

A recently developed, time-accurate multigrid viscous solver has been extended to handle quasi-three-dimensional effects and applied to the first stage of a modern transonic compressor. Interest is focused on the inlet guide vane (IGV):rotor interaction where strong sources of unsteadiness are to be expected. Several calculations have been performed to predict the stage operating characteristics. Flow structures at various mass flow rates, from choke to near stall, are presented and discussed. Comparisons between unsteady and steady pitch-averaged results are also included in order to obtain indications about the capabilities of steady, multi-row analyses.


Sign in / Sign up

Export Citation Format

Share Document