A Numerical and Experimental Evaluation of the Turbulent Heat Flux in a Heated Jet in the Crossflow


Book Description

The injection of fully-developed turbulent heated air from a tube into a cooler turbulent duct flow is examined, as an analogy to film cooled turbine blades. Scale Resolving Simulations (SRS) are used to examine the flow numerically. A Detached Eddy Simulation (DES) methodology is examined but found to be ineffective at correctly capturing the physics of the flow. A Large Eddy Simulation (LES) numerical model is developed and applied in which tube and duct turbulence inflow effects are emulated using a divergence-free synthetic eddy method (SEM). The LES sensitivity to the synthetic inflow toggled on and off. The effects of turbulence in the coolant tube are found to the most critical for accurate prediction. For direct comparison, a hot-wire experiment is conducted within the ERB test cell SW-6 at NASA Glenn Research Center. Excellent agreement is obtained for these numerical and experimental results related to velocity, temperature, and heat flux, for a blowing ratio for 1.2, and involving a 36 K temperature difference. The relative effect on the solutions of tube and duct inflow turbulence is systematically evaluated. The impact of inherent low-pass filtering of temperature measurements and probe wire offset on the experimental results are addressed. The validity of the gradient diffusion hypothesis, fundamental to Reynolds-Averaged Navier-Stokes (RANS) models, is evaluated.
















Nanofluids


Book Description

Nanofluids are a new class of heat transfer fluids engineered by dispersing and stably suspending nanoparticles in traditional heat transfer fluids. Recently they have obtained global attention from the scientific community owing to their unique properties and significant applications in different engineering fields. Nanofluids: Preparation, Applications and Simulation Methods provides a comprehensive review of recent advances in this important research field. Different approaches for preparing some remarkable families of nanofluids such as aluminum oxide-based nanofluids, CuO/Cu-based nanofluids, carbon nanotubes/graphene-based nanofluids, ZnO-based nanofluids, Fe3O4-based nanofluids, and SiO2-based nanofluids are discussed in detail as well as their current and potential applications. Different approaches for numerical, semi-analytical and analytical simulations are also discussed including molecular dynamics, the Lattice Boltzmann method, and spectral methods, as well as advanced analytical techniques such as the Differential Transform Method, the Homotopy Analysis Method, and Optimal Homotopy Analysis. The book will be a valuable reference resource for academic and industrial researchers, materials scientists and engineers, nanotechnologists, and chemists working in the development of nanomaterials and nanofluids for heat transfer in energy and engineering applications. - Covers the synthesis of nanostructures, preparation of nanofluids, different applications and proposed models for fluid mechanics and heat transfer - Presents recent advances on preparation methods, including green chemistry-based methods for preparation of nanomaterials and nanofluids - Includes novel model-based approaches such as molecular dynamics and Lattice Boltzmann methods - Delves into applications in renewable energy technologies and thermal management - Contains a Semi-analytical approach for solving Time-Fractional Navier-Stokes Equation







Masters Theses in the Pure and Applied Sciences


Book Description

Masters Theses in the Pure and Applied Sciences was first conceived, published, and dis seminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the ac tivity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all concerned if the printing and distribution of the volume were handled by an international publishing. house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Corporation of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 25 (thesis year 1980) a total of 10,308 theses titles from 27 Canadian and 214 United States universities. We are sure that this broader base for theses titles reported will greatly enhance the value of this important annual reference work. While Volume 25 reports theses submitted in 1980, on occasion, certain universities do report theses submitted in previous years but not reported at the time.




Mechanical Engineering


Book Description