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Aerodynamic shape optimization processes are often used for complex problems that meet single or multi-objective design requirements. The robust aerodynamic shape optimization techniques with a high number of design variables that consider uncertainties have a huge computational burden compared to the traditional aerodynamic shape optimization techniques without considering uncertainties. To overcome this issue, in this study, the proper orthogonal decomposition is integrated with the inductive design exploration method to use for the robust shape optimization of the ONERA M6 wing. The proper orthogonal decomposition method is utilized for reducing the number of design variables of the wing geometry. The cost due to the computational fluid dynamics analysis is mitigated by incorporating the proper orthogonal decomposition with a surrogate modeling technique called the radial basis function. The robust optimization is conducted by the proposed approach based on the inductive design exploration method by accounting for uncertainties of the Mach number in the transonic flow regime. The agreement between the performance predictions of the robust designs and the computational fluid dynamics analysis results showed the effectiveness of the proposed approach. © 2024 Gazi Universitesi Muhendislik-Mimarlik. All rights reserved.

Aerodynamic shape optimization processes are often used for complex problems that meet single or multi-objective design requirements. The robust aerodynamic shape optimization techniques with a high number of design variables that consider uncertainties have a huge computational burden compared to the traditional aerodynamic shape optimization techniques without considering uncertainties. To overcome this issue, in this study, the proper orthogonal decomposition is integrated with the inductive design exploration method to use for the robust shape optimization of the ONERA M6 wing. The proper orthogonal decomposition method is utilized for reducing the number of design variables of the wing geometry. The cost due to the computational fluid dynamics analysis is mitigated by incorporating the proper orthogonal decomposition with a surrogate modeling technique called the radial basis function. The robust optimization is conducted by the proposed approach based on the inductive design exploration method by accounting for uncertainties of the Mach number in the transonic flow regime. The agreement between the performance predictions of the robust designs and the computational fluid dynamics analysis results showed the effectiveness of the proposed approach. © 2024 Gazi Universitesi Muhendislik-Mimarlik. All rights reserved.

This chapter aims to provide information on classification, types, design methodology, and selection of heat exchangers (HEX), focusing on plate HEX. The details of a software developed based on correlations obtained using experimental data are presented. Plate HEX literature is explained in detail and the correlations in literature are used in the developed HEX selection software for comparison with the new correlations. The analysis shows that specific correlations based on experimental data are necessary to be used with plates utilized in HEX selection, since the plate geometries are unique and need specific correlations to reflect their properties correctly. © 2018 Elsevier Inc. All rights reserved.

In this study, an experimental set-up for testing chevron type gasketed plate heat exchangers is utilized to investigate the thermal and hydraulic characteristics of different plate geometries. The experiments can be performed using various number of plates and wide range of plate sizes. The experiments are carried out for different temperatures, flow rates, and number of plates so that the Reynolds numbers (300-5250) and Prandtl numbers varies for all plates that have 30 degrees of chevron angle. Correlations are derived for Nusselt number and friction factor by using the experimental results.

In this study, a computer program is developed to design and compare gasketed plate heat exchangers with double pipe heat exchangers. The computer program is coded in MATLAB. The user interface of the program is prepared in MATLAB Guide. The program uses hot and cold fluid properties as input data and calculates the characteristics o gasketed plate heat exchangers and double pipe heat exchangers designed for the given conditions. The outputs for gasketed plate heat exchanger design include number of plates, effective area, total heat transfer coefficient, pressure losses, pumping power and cost, whereas, the outputs for double pipe heat exchanger selection are: pump power, total number of hairpins, effective area, pressure drop, total heat transfer coefficient and cost. Correlations selected from literature are used in the program for the analysis. Water is selected as the working fluid to be able to make the comparison. The program compares the heat exchangers based on cost, effective area, and pumping power. The computer program is also used to understand and compare operational behaviors of these two heat exchangers under different operating conditions. Copyright © 2010 by ASME., ASME Turkey Section;Loughborough University

This chapter mainly focuses on numerical studies performed to analyze a plate heat exchanger composed of specific plates and the experimental validation of the numerical study. Different turbulence models, mainly k-?, RNG k-?, EARSM k-?, k-?, and SST k-?, are used and compared in computational fluid dynamics analysis. First, the numerical methodology is validated with the help of experiments. The effects of several geometrical properties on the performance of the exchangers are investigated numerically with the help of the validated methodology. These geometrical properties include channel height, wave amplitude, and distribution channels. New plate designs with better thermal and hydraulic performance are obtained with the utilization of experimentally validated computational fluid dynamics (CFD) techniques. © 2017 by Taylor ; Francis Group, LLC.

Recently, TOBB University of Economics and Technology was awarded a grant for a project on 'Design, Construction and Test of Hydraulic Turbines' from Turkish Ministry of Development. The project includes Computational Fluid Dynamics (CFD) aided hydraulic and structural design, geometry optimization, manufacturing and testing of hydraulic turbines. The main objective of the research presented here is to design a hydro turbine test stand which tests the performance and cavitation characteristics of turbine models according to standards. The paper describes the characteristics of the designed test stand. © 2013 IEEE., Abant Izzet Baysal Universitesi;Cankiri Karatekin Universitesi

This chapter aims to provide information on classification, types, design methodology, and selection of heat exchangers (HEX), focusing on plate HEX. The details of a software developed based on correlations obtained using experimental data are presented. Plate HEX literature is explained in detail and the correlations in literature are used in the developed HEX selection software for comparison with the new correlations. The analysis shows that specific correlations based on experimental data are necessary to be used with plates utilized in HEX selection, since the plate geometries are unique and need specific correlations to reflect their properties correctly. © 2018 Elsevier Inc. All rights reserved.

Supersonic transport (SST) technology has widely been investigated. Flow characteristics become complicated in supersonic conditions, and aerodynamic shape optimization studies are required for the design process of supersonic vehicles. An optimized aircraft is very efficient in terms of fuel consumption and pressure losses. This study focuses on the aerodynamic design and shape optimization of a supersonic business jet. For this purpose, a design algorithm (BF-I) is developed with the help of historical trends of supersonic aircrafts, commercial aircrafts and experimental correlations. After obtaining the baseline geometry, a gradient-based optimization is employed to get optimum results for the design. The developed numerical methodology is tested for both 2D and 3D geometries. CFD analysis are performed by using SU2 (Stanford University Unstructured) solver that has high performance for compressible flows. Euler equations are used for the analyses. © 2015, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

In this study, laser energy deposition is used as a flow control technique. The effects of laser energy deposition over an open rectangular supersonic cavity flow to realize the capability of the energy deposition for reduction of the pressure fluctuations and relative sound pressure levels are examined numerically. The simulations are performed for the cases both with and without energy deposition for unsteady flow over a two dimensional cavity at a free stream Mach number of 1.5. The length to depth ratio of the cavity (L/D) is 5.07 which represents an open cavity configuration. The Reynolds-averaged compressible time dependent Navier Stokes equations in two dimensions are solved using the flow solver ANSYS Fluent. The k-w model is used as a turbulence model. The application of the laser deposition is modeled by using the Gaussian temperature profile assuming the density within the spot is initially uniform. The results obtained from the simulation performed for 5mJ of energy show that laser energy deposition provides small reduction for SPL values. Also, the impacts of frequency, location, and amount of laser energy deposition will be investigated and the results will be presented in the final paper.

In this study, an experimental set-up for testing chevron type gasketed plate heat exchangers is utilized to investigate the thermal and hydraulic characteristics of different plate geometries. The experiments can be performed using various number of plates and wide range of plate sizes. The experiments are carried out for different temperatures, flow rates, and number of plates so that the Reynolds numbers (300-5250) and Prandtl numbers varies for all plates that have 30 degrees of chevron angle. Correlations are derived for Nusselt number and friction factor by using the experimental results.

In this study, a computer program is developed to design and compare gasketed plate heat exchangers with double pipe heat exchangers. The computer program is coded in MATLAB. The user interface of the program is prepared in MATLAB Guide. The program uses hot and cold fluid properties as input data and calculates the characteristics o gasketed plate heat exchangers and double pipe heat exchangers designed for the given conditions. The outputs for gasketed plate heat exchanger design include number of plates, effective area, total heat transfer coefficient, pressure losses, pumping power and cost, whereas, the outputs for double pipe heat exchanger selection are: pump power, total number of hairpins, effective area, pressure drop, total heat transfer coefficient and cost. Correlations selected from literature are used in the program for the analysis. Water is selected as the working fluid to be able to make the comparison. The program compares the heat exchangers based on cost, effective area, and pumping power. The computer program is also used to understand and compare operational behaviors of these two heat exchangers under different operating conditions. Copyright © 2010 by ASME., ASME Turkey Section;Loughborough University

This chapter mainly focuses on numerical studies performed to analyze a plate heat exchanger composed of specific plates and the experimental validation of the numerical study. Different turbulence models, mainly k-?, RNG k-?, EARSM k-?, k-?, and SST k-?, are used and compared in computational fluid dynamics analysis. First, the numerical methodology is validated with the help of experiments. The effects of several geometrical properties on the performance of the exchangers are investigated numerically with the help of the validated methodology. These geometrical properties include channel height, wave amplitude, and distribution channels. New plate designs with better thermal and hydraulic performance are obtained with the utilization of experimentally validated computational fluid dynamics (CFD) techniques. © 2017 by Taylor ; Francis Group, LLC.

Recently, TOBB University of Economics and Technology was awarded a grant for a project on 'Design, Construction and Test of Hydraulic Turbines' from Turkish Ministry of Development. The project includes Computational Fluid Dynamics (CFD) aided hydraulic and structural design, geometry optimization, manufacturing and testing of hydraulic turbines. The main objective of the research presented here is to design a hydro turbine test stand which tests the performance and cavitation characteristics of turbine models according to standards. The paper describes the characteristics of the designed test stand. © 2013 IEEE., Abant Izzet Baysal Universitesi;Cankiri Karatekin Universitesi

In this study, laser energy deposition is used as a flow control technique. The effects of laser energy deposition over an open rectangular supersonic cavity flow to realize the capability of the energy deposition for reduction of the pressure fluctuations and relative sound pressure levels are examined numerically. The simulations are performed for the cases both with and without energy deposition for unsteady flow over a two dimensional cavity at a free stream Mach number of 1.5. The length to depth ratio of the cavity (L/D) is 5.07 which represents an open cavity configuration. The Reynolds-averaged compressible time dependent Navier Stokes equations in two dimensions are solved using the flow solver ANSYS Fluent. The k-w model is used as a turbulence model. The application of the laser deposition is modeled by using the Gaussian temperature profile assuming the density within the spot is initially uniform. The results obtained from the simulation performed for 5mJ of energy show that laser energy deposition provides small reduction for SPL values. Also, the impacts of frequency, location, and amount of laser energy deposition will be investigated and the results will be presented in the final paper.

Supersonic transport (SST) technology has widely been investigated. Flow characteristics become complicated in supersonic conditions, and aerodynamic shape optimization studies are required for the design process of supersonic vehicles. An optimized aircraft is very efficient in terms of fuel consumption and pressure losses. This study focuses on the aerodynamic design and shape optimization of a supersonic business jet. For this purpose, a design algorithm (BF-I) is developed with the help of historical trends of supersonic aircrafts, commercial aircrafts and experimental correlations. After obtaining the baseline geometry, a gradient-based optimization is employed to get optimum results for the design. The developed numerical methodology is tested for both 2D and 3D geometries. CFD analysis are performed by using SU2 (Stanford University Unstructured) solver that has high performance for compressible flows. Euler equations are used for the analyses. © 2015, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

A Computational Fluid Dynamics (CFD) study is conducted to investigate the unsteady, turbulent supersonic cavity flow characteristics and to control the severe effects of the flow field. Simulations of Mach 1.5 supersonic cavity flow with a length to depth ratio of 5.07 are performed using commercial ANSYS Fluent solver. Unsteady density-based Reynolds Averaged Navier-Stokes equations are modeled with standard k-? turbulence model. Both baseline simulations with no control and simulations with passive and active control methods are examined. Implemented passive control methods are trailing edge wall inclination, cavity entrance cover plate, and wall spoilers. Microjet blowing is applied as an active control method. For further investigation of the flow field and to distinguish the dominant features of the controlled and uncontrolled cases, Proper Orthogonal Decomposition (POD) is applied to velocity data obtained from the inside of the cavity. CFD and POD studies represent promising results for flow control in terms of suppressing undesired effects of cavity flow oscillations. © 2019, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

A Computational Fluid Dynamics (CFD) study is conducted to investigate the unsteady, turbulent supersonic cavity flow characteristics and to control the severe effects of the flow field. Simulations of Mach 1.5 supersonic cavity flow with a length to depth ratio of 5.07 are performed using commercial ANSYS Fluent solver. Unsteady density-based Reynolds Averaged Navier-Stokes equations are modeled with standard k-? turbulence model. Both baseline simulations with no control and simulations with passive and active control methods are examined. Implemented passive control methods are trailing edge wall inclination, cavity entrance cover plate, and wall spoilers. Microjet blowing is applied as an active control method. For further investigation of the flow field and to distinguish the dominant features of the controlled and uncontrolled cases, Proper Orthogonal Decomposition (POD) is applied to velocity data obtained from the inside of the cavity. CFD and POD studies represent promising results for flow control in terms of suppressing undesired effects of cavity flow oscillations. © 2019, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.