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Full-Text Articles in Thermodynamics
Conceptual Exploration Of Film Cooling Techniques In Hydrogen Gas Turbines, Wen Wu
Conceptual Exploration Of Film Cooling Techniques In Hydrogen Gas Turbines, Wen Wu
Student Research Symposium (SRS)
Film cooling is a key heat transfer technique that protects gas turbine blades from extreme temperatures, allowing higher turbine inlet temperatures and greater thermal efficiency. It works by ejecting a thin layer of cooler air from the compressor through small holes onto the hot surface, creating a protective film layer that lowers surface temperature and reduces thermal stress on blades. This process is vital in power generation and propulsion systems that operate near material limits. With growing emphasis on sustainability, film cooling has gained new importance in hydrogen-fueled gas turbines. Hydrogen combustion creates water vaper and low-density exhaust gases, which …
Benchmarking Of A Sco2 Heat Exchanger Flow Loop, David Velasco
Benchmarking Of A Sco2 Heat Exchanger Flow Loop, David Velasco
Doctoral Dissertations and Master's Theses
Heat transfer of supercritical carbon dioxide (sCO2) was studied experimentally by commissioning a sCO2 flow loop featuring a horizontal tube-in-tube counterflow heat exchanger with a circular cross section. The main objective was to establish experimental heat transfer research capabilities for sCO2 at Embry-Riddle Aeronautical University’s (ERAU) Thermal Science Lab. sCO2 experiences a drastic change in thermophysical properties near its critical point that results in unique heat transfer characteristics. The high pressures at which sCO2 exists make the large gradients in thermophysical and transport properties difficult to study, experimentally and numerically. However, understanding the heat transfer characteristics and thermophysical behavior of …
Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer
Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer
Publications
In order to increase the accuracy of temporal solutions, reduce the computational cost of time marching, and improve the stability associated with collisions for the finite-volume discrete Boltzmann method, an advanced implicit Bhatnagar-Gross-Krook (BGK) collision model using a semi-Lagrangian approach is proposed in this paper. Unlike existing models, in which the implicit BGK collision is resolved either by a temporal extrapolation or by a variable transformation, the proposed model removes the implicitness by tracing the particle distribution functions (PDFs) back in time along their characteristic paths during the collision process. An interpolation scheme is needed to evaluate the PDFs at …
Thermal Removal Of Carbon Dioxide From The Atmosphere: Energy Requirements And Scaling Issues, Ted Von Hippel
Thermal Removal Of Carbon Dioxide From The Atmosphere: Energy Requirements And Scaling Issues, Ted Von Hippel
Publications
I conduct a systems-level study of direct air capture of CO2 using techniques from thermal physics. This system relies on a combination of an efficient heat exchanger, radiative cooling, and refrigeration, all at industrial scale and operated in environments at low ambient temperatures. While technological developments will be required for such a system to operate efficiently, those developments rest on a long history of refrigeration expertise and technology, and they can be developed and tested at modest scale. I estimate that the energy required to remove CO2 via this approach is comparable to direct air capture by other techniques. The …