## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Validation and application of source based CFD for numerical simulations and optimizations in turbine-related configurations

**ABSTRACT**

In order to accelerate the numerical simulation and optimization of gas turbine-related configurations, a source based CFD (SCFD) approach is developed for flow and heat transfer simulations. Different sources depending on the fluid porosity at each grid node in the computational domain are introduced to the continuity, momentum, energy and turbulence model equations, so that both the fluid and solid regions can be solved as one region. In the present paper, test cases including a ribbed channel and a winglet shrouded turbine cascade with tip injection are investigated using the SCFD and CFD with body-fitted meshes (BCFD). Impacts of grid clustering and turbulence model equation sources on the SCFD precision are examined. Numerical results show that the SCFD predicts consistent aero-thermal performance with the BCFD and experiments. The validated SCFD scheme is then employed in a response surface optimization of tip jet holes on the winglet shroud tip. A jet arrangement with the minimum energy loss and injection mass flow rate is obtained, indicating that source based predictions can be applied to the preliminary aero-thermal design of turbine blades.

**KEYWORDS**

PAPER SUBMITTED: 2019-04-04

PAPER REVISED: 2019-06-11

PAPER ACCEPTED: 2019-06-13

PUBLISHED ONLINE: 2019-07-06

- Johnson, G.J.J., King, P.I., Clark, J. P., Clark J.P., Ooten M.K., Design Optimization Methods for Improving HPT Vane Pressure Side Cooling Properties Using Genetic Algorithms and Efficient CFD, Report No. AIAA 2012-0326, Nashville, Tennessee, 2012.
- Amaral, S., Verstraete, T., Van den Braembussche, R., Arts, T., Design and Optimization of the Internal Cooling Channels of High Pressure Turbine Blade - Part I, Methodology, J. Turbomach., 132(2010), 2, pp. 021013.
- Maffulli, R., He, L., Wall Temperature Effects on Heat Transfer Coefficient for High-Pressure Turbines, J. Propul. Power, 30(2014), 4, pp.1080-1090.
- Ravi, D., Parammasivam, K. M., Enhancing Film Cooling Effectiveness in a Gas Turbine End-Wall with a Passive Semi Cylindrical, Thermal Science, OnLine-First (2018), pp:1-1.
- Xie, Y.H., Ye, D.T., Shen, Z.Y., Numerical Study on Film Cooling and Convective Heat Transfer Characteristics in the Cutback Region of Turbine Blade Trailing Edge, Thermal Science, 2016, 20(3): S643-S649.
- Khadra, K., Angot, P., Parneix, S., et al. Fictitious Domain Approach for Numerical Modeling of Navier-Stokes Equations, Int. J. Numer. Methods Fluids, 34(2000), 8, pp.651-684.
- Wang, Y.L., Shao, X.M., Study on Flow of Power-Law Fluid Through an Infinite Array of Circular Cylinders with Immersed Boundary-Lattice Boltzmann Method, Thermal Science, 2012, 16(5): 1451-1455.
- He, L., and Tafti, D., Evaluating the Immersed Boundary Method in a Ribbed Duct for the Internal Cooling of Turbine Blades, Report No. ASME GT2015-43953, MontrĂ©al, Canada , 2015.
- Lad, B., He, L., Romero, E., Validation of the Immersed Mesh Block (IMB) Approach Against a Cooled Transonic Turbine Stage, Report No. Report No.GT2012-68779, Copenhagen, Denmark, 2012.
- Andrei, L., Innocenti, L., Andreini, L., Facchini, B., Winchler, L., Film Cooling Modeling for Gas Turbine Nozzles and Blades, Validation and Application, J. Turbomach., 139(2016), 1, p.011004.
- Dbouk, T., A Review about the Engineering Design of Optimal Heat Transfer Systems Using Topology Optimization, Appl. Therm. Eng., 112(2017), pp. 841-854.
- Pietropaoli, M., Ahlfeld, R., Montomoli, F., Ciani, A., D'Ercole, M., Design for Additive Manufacturing, Internal Channel Optimization, Report No.ASME GT2016-57318, Seoul, South Korea, 2016.
- Dilgen, C.B., Dilgen, S.B., Fuhrman, D.R., Sigmund, O., Lazarov, B.S., Topology Optimization of Turbulent Flow, Comput. Methods Appl. Mech. Engrg., 331(2018), pp. 363-393.
- Iseler, J., Martin, T.J., Flow Topology Optimization of a Cooling Passage for a High Pressure Turbine Blade, Report No.ASME G2017-63618, Charlotte, USA, 2017.
- Wilcox, D.C., Multiscale Model for Turbulent Flows, AIAA J., 26(1988), 11, pp. 1311-1320.
- Menter, F.R., Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications, AIAA J., 32(1994),8,pp.1598-1605.
- Ansys, Inc., ANSYS CFX-Solver Modeling Guide, ANSYS, Inc., Canonsburg, USA, 2013.
- Acharya, S., Dutta, S., Myrum, T.A., Heat Transfer in Turbulent Flow Past a Surface-Mounted Two-Dimensional Rib, J. Heat Transfer, 120(1998), 3, pp.724-734.
- Celik, I.B., Ghia, U., Roache, P.J., Freitas, C.J., Coleman, H., Raad, P.E., Procedure for Estimation and Reporting of Uncertainty Due to Discretization in CFD Applications, J. Fluids Eng., 130(2008), 7, p.078001.
- Kang, C., Yang, K.S., Heat transfer enhancement in turbulent ribbed-pipe flow, J. Heat Transfer, 139(2017), 7, p.071901.
- Baughn, J.W., Hoffman, M.A., Takahashi, R.K., Launder, B.E., Local Heat Transfer Downstream of an Abrupt Expansion in a Circular Channel with Constant Wall Heat Flux, J. Turbomach., 106(1984), 4, pp.789-796.
- Liu, Y., Zhang, T.L., Zhang, M., Zhang, M.C., Lu, H.W., Numerical and Experimental Investigation of Aerodynamic Performance for a Straight Turbine Cascade with a Novel Partial Shroud, J. Fluids Eng., 138(2015), 3, p. 031206.
- Zhang, M., Liu, Y., Zhang, M.C., Mo, B.X., Aerodynamic performance of tip injections for a winglet-shrouded linear turbine cascade, Report No.ASME GT2017-63679, Charlotte, USA, 2017.
- Han, J.C., Fundamental Gas Turbine Heat Transfer, J. Therm. Sci. Eng. Appl., 5(2013), 2, p.021007.