Ciencias Exactas y Ciencias de la Salud
http://hdl.handle.net/11285/551039
2019-12-14T21:31:23ZStudy on the influence of geometrical parameters to enhance heat transfer in a finned cylindrical segment, incorporating vortex generators.
http://hdl.handle.net/11285/633085
Study on the influence of geometrical parameters to enhance heat transfer in a finned cylindrical segment, incorporating vortex generators.
Chilaca Tarango, Anuar Samuel
The present work addresses the simulation of geometries considering forced convection of turbulent flow for the thermal optimization of a generator of a water-ammonia absorption refrigeration system, for which purpose, several simulations were carried out on ANSYS Fluent, varying the geometric parameters in order to define the optimal design for the generator. In the first part, a geometrical analysis of the previously geometry proposed for the construction of the generator is presented, evaluating those geometrical factors that enhance the heat transfer. The results obtained from the simulations are used to calculate the global heat transfer coefficient by convection, as well as the average Nusselt number. High heat transfer coefficients were found where geometries shows specific arrangements that modify the evolution of the flow, those changes in the flow contributes to the higher mixed and to the heat transfer. The second part of the thesis analyze the modification of arrangement and evaluate the introduction of different types of fin geometries. Realistic and manufacturable geometries were considered for maximization of thermal heat transfer coefficient and also the minimization of friction forces. In order to compare these various geometries, a set of standard conditions were required. Finally, the thesis contemplates the incorporation of Vortex Generators (VG) to enhance the heat transfer along the generator. Vortex generators is one of the passive methods to generate streamwise vortices that create high turbulence in fluid flow over heat transfer surfaces. VG have shown to be an effective way to increase the heat transfer coefficient, decreasing the thermal resistance of the sublayer adjacent to the wall immediately where the viscous effects of the sublayer are dominant. The increase of turbulence of the fluid flow in the main stream have shown positive effects on the heat transfer. The thesis evaluates the present research of VG and contemplate the simulation of the incorporation of an array of VG over the surface of a previously finned- cylindrical geometry of generator, contrasting the immersion of the VG's to baseline geometry, the effects on the pressure drop are also studied. Subsequently, the incorporation of a modified annular winglet vortex generator over the generator surface was also evaluated. The results were compared to the no VG fin type geometry. The results show that the heat transfer increases considerably, but an increase on the pressure drop is also observed.
2018-05-25T00:00:00ZDeveloping a surface with dew enhancing properties to harvest water from the environment by treating a clay substrate with SIO2-OTS nanoparticles
http://hdl.handle.net/11285/633084
Developing a surface with dew enhancing properties to harvest water from the environment by treating a clay substrate with SIO2-OTS nanoparticles
The demand for drinkable water by the world population is increasing each year due to the aggressive exploitation of natural resources and bodies of water. Mexico is a country rich in natural resources, but its population’s demand for drinking water has led to a rapid deterioration of these. Additionally, with the population spread throughout the national territory many communities have found themselves isolated and with few commodities- water is scarce. Thus, it is imperative to develop an alternative that allows the acquisition of water for the population and various communities who require this element vital for life. There is currently a race of diverse solutions for this world-wide problem. While some studies choose high cost mechanical means, others are seeking low cost solutions by the creation of new materials with nanotechnology and biomimecry. However, neither has created a proper surface or method by which such humidity can be harvested and used by the population. Thus, this proposal, developed at the Instituto Tecnologico y de Estudios Superiores de Monterrey, offers a solution focused on the replication of the Stenocara Beetle through the creation of a hybrid surface on a clay substrate with SiO2-OTS particles that harvests the environment’s humidity in an alternative that can be introduced into the construction industry.
Clasificación de espacios urbanos a gran escala a partir de un estudio de percepción y datos del INEGI de la ciudad de Puebla, San Pedro Cholula y San Andrés Cholula.
http://hdl.handle.net/11285/633082
Clasificación de espacios urbanos a gran escala a partir de un estudio de percepción y datos del INEGI de la ciudad de Puebla, San Pedro Cholula y San Andrés Cholula.
El presente trabajo consiste en un estudio enfocado a la automatización de la clasificación
de espacios urbanos de acuerdo a un estudio de percepción y datos sociodemográficos
del INEGI. En la actualidad no se cuenta con un proceso sistematizado
que facilite la toma de decisiones en relación a una planeación urbana adecuada. Por
esta razón, se llevó a cabo un estudio para medir la percepción humana en 5 rubros:
belleza arquitectónica, contaminación, diversión, riqueza y seguridad. La información
recabada se utilizó para proponer un modelo de Machine learning que pueda realizar un
reconocimiento de patrones entre la percepción obtenida y los datos demográficos. Este
primer acercamiento pretende denotar los puntos clave necesarios para el desarrollo de
dicho modelo y su posible implementación.
Geometric phase interferometer for measuring optical systems' polarization parameters
http://hdl.handle.net/11285/633081
Geometric phase interferometer for measuring optical systems' polarization parameters
In this dissertation experimental techniques based on interferogram comparison were used to
extract the geometric phase of a classical light beam. When a light beam passes through a
general optical system, one obtains specific polarization information. The extracted geometric phase allows for the obtainment of parameters such as eigenpolarizations, eigenvalues, retardance, and the equivalent Jones matrix of the system. In addition, it is experimentally demonstrated that it is also possible to determine the Stokes parameters of a uniformly polarized light beam using only the acquired geometric phase. The results presented are in particular for a photonic system of elliptical wave-plate retarders or polarizers, but it is essential to realize that this same idea can be extrapolated to other systems.