Modelado del impacto en dos dimensiones de secciones típicas de botes de planeo con entrada asimétrica y velocidad horizontal

The 2D impact phenomenon in calm water, considering asymmetric entry and asymmetric entry withhorizontal velocity is studied. The analysis was performed by using a commercial CFD software (STARCCM+©). The results obtained from the simulations are: pressure distribution, force and roll moment.The study was carried out for typical planing boat sections. Furthermore, the critical conditions requiredfor flow separation from the keel are also determined. The results are compared with models and resultsobtained from some authors and they present very good agreement.En este trabajo se modela la entrada asimétrica de secciones con ángulo de astilla muerta variable y velocidad horizontal con la ayuda del software CFD Star-CCM+, con el cual se determinan la distribución de presión, la variación de fuerza y momento de rolido durante impacto. Los resultados obtenidos son comparados con los modelos de otros autores para entrada asimétrica logrando gran similitud. Se introduce el efecto de la velocidad horizontal y se analiza el comportamiento de este tipo de secciones, y también se evalúan las condiciones críticas que dan origen a la separación del flujo de la quilla para diferentes cuñas

Experimental data for an air-conditioning system identification

In this article, data from a 3.5kW mini split air conditioning is presented. A screening 23 design experiment was performed to evaluate the effects of indoor air temperature, absolute humidity and evaporator fan speed in the performance of the air conditioning. This dataset also includes noise factors as outdoor air temperature, fans energy consumption and response as indoor air exit conditions.Universidad del Norte, Universidad de la Costa

Diseño de un plan de acción para la implementación de un sistema de seguridad, salud en el trabajo y ambiente para contratistas según guía RUC del sector transporte (Rev 4 2014) en la empresa Blue Marlin S.A.S.

En este proyecto se lleva a cabo el diseño de un plan de acción basado en el diagnóstico inicial del formato de autoevaluación del sistema ssta ruc (rev 1813/12/20) y bajo lineamientos de la guía del sistema ssta ruc sector transporte (rev 4-14/02/20) 2014 (Registro Único para Contratistas) en la empresa BLUE MARLIN S.A.S. El diseño del sistema de gestión SSTA está basado en cuatro ejes principales: 1. Liderazgo y compromiso gerencial, 2. Desarrollo y ejecución del SSTA, 3. Administración del riesgo y 4. Evaluación y monitoreo. El primero se encarga del apoyo y compromiso por parte de la alta gerencia. En la segunda etapa se se lleva a cabo la creación de procedimientos, manuales, guías, etc. En la tercera etapa se identifican todas aquellas condiciones peligrosas que generan consecuencias negativas (accidentes o casi accidentes) sobre las personas y el medio ambiente, para ello se utiliza herramientas como entrevistas, estadísticas (en caso de existir), y la matriz de riesgos en personas y ambiente. Finalmente la cuarta etapa garantiza el correcto funcionamiento del sistema SSOA propuesto, mediante la utilización de distintos indicadores se evalúa los diferentes aspectos del sistema, en caso de resultados negativos, entonces se procederá a plantear nuevas soluciones. Lo anterior es un bucle retroalimentador del sistema que permite su mejoramiento continuo.This project is carried out to design a plan of action based on the initial diagnosis of SSTA autoevaluation management system (rev 18-13/12/20) (Safety, Health and Environment at Work) under the guidelines of the RUC (rev 4-14/02/20) 2014 (Uniform Contractor Registration) in the company BLUE MARLINSAS. The program design is based on SSTA management system in four main areas: 1 Leadership and management commitment, 2 Development and implementation of SSTA, 3 and 4 Risk Management evaluation and monitoring. The first is responsible for the support of senior management, this gives it greater worker acceptance. In the second stage all those dangerous conditions that generate negative consequences (accidents or near accidents) on people and the environment, tools are goingto be used to do interviews, statistics (if any), and the matrix of risk are identified people and environment. The third part is done creating procedures, manuals, guides, etc. That will reduce or if possible eliminate the hazards found in the previous phase. Finally the fourth step ensures the proper functioning of the proposed SSOA system, using different indicators of different aspects of the system is evaluated in case of negative results, then proceed to propose new solutions. This is a feedback loop system that allows for continuous improvement

Eficiencia energética en edificaciones del Caribe

Como parte de los estudios realizados en el Área Estratégica de Investigación en Energía, los grupos de investigación en Arquitectura y Diseño y Uso Racional de la Energía y Preservación del Medio Ambiente (Urema) de Uninorte realizan un estudio para analizar el comportamiento térmico de materiales de construcción regularmente utilizados en la región Caribe colombiana como envolventes de las edificaciones, con el propósito de recomendar al sector de la construcción y a la ciudadanía en general cuáles son los productos adecuados en ahorro energético en lo que se refiere a procesos de enfriamiento.Arquitectos e ingenieros mecánicos de Uninorte desarrollan una investigación, pionera en Colombia, que apunta al fomento del uso de materiales de construcción eficientes en ahorro energético para el enfriamiento de edificaciones en climas tropicales y húmedos.Universidad del Norte. Área Estratégica de Investigación en Energía

Innovación en terapia respiratoria para recién nacidos

Los grupos de investigación de Uninorte Biotecnología y Uso Racional de la Energía y Preservación del Medio Ambiente (UREMA) y la primera spin off de la institución: Biotecnología & Bioingeniería Core S.A, diseñaron un dispositivo compacto y portátil para terapia respiratoria CPAP en niños prematuros, que resulta innovador frente a los que existen actualmente en el mercado.La terapia CPAP (presión positiva continua en la vía aérea) es un sistema de apoyo para neonatos, especialmente para aquellos prematuros o de bajo peso que respiran con dificultad. Los dispositivos CPAP tradicionales sólo pueden utilizarse en unidades de cuidados intensivos. En la mayoría de países de América Latina como Colombia existe la necesidad de suministrar esta terapia en centros de salud y de ser transportada en ambulancias.Biotecnología & Bioingeniería Core S.A. Universidad del Norte: Centro de Emprendimiento y Dirección de Investigación, Desarrollo e Innovació

Thermal optimization of a dual pressure goswami cycle for low grade thermal sources

This paper presents a theoretical investigation of a new configuration of the combined power andcoolingcycleknownastheGoswamicycle. Thenewconfigurationconsistsoftwoturbinesoperating at two different working pressures with a low-heat source temperature, below 150 °C. A comprehensive analysis was conducted to determine the effect of key operation parameters such as ammonia mass fraction at the absorber outlet and boiler-rectifier, on the power output, cooling capacity, effective first efficiency, and effective exergy efficiency, while the performance of the dual-pressure configuration was compared with the original single pressure cycle. In addition, a Pareto optimization with a genetic algorithmwasconductedtoobtainthebestpowerandcoolingoutputcombinationstomaximizeeffective first law efficiency. Results showed that the new dual-pressure configuration generated more power than the single pressure cycle, by producing up to 327.8 kW, while the single pressure cycle produced up to 110.8 kW at a 150 °C boiler temperature. However, the results also showed that it reduced the cooling output as there was less mass flow rate in the refrigeration unit. Optimization results showed that optimum effective first law efficiency ranged between 9.1% and 13.7%. The maximum effective first law efficiency at the lowest net power (32 kW) and cooling (0.38 kW) outputs was also shown. On the other hand, it presented 13.6% effective first law efficiency when the net power output was 100 kW and the cooling capacity was 0.38 kW

Energy, exergy and economic evaluation comparison of small-scale single and dual pressure organic Rankine cycles integrated with low-grade heat sources

Low-grade heat sources such as solar thermal, geothermal, exhaust gases and industrial waste heat are suitable alternatives for power generation which can be exploited by means of small-scale Organic Rankine Cycle (ORC). This paper combines thermodynamic optimization and economic analysis to assess the performance of single and dual pressure ORC operating with different organic fluids and targeting small-scale applications. Maximum power output is lower than 45 KW while the temperature of the heat source varies in the range 100-200 °C. The studied working fluids, namely R1234yf, R1234ze(E) and R1234ze(Z), are selected based on environmental, safety and thermal performance criteria. Levelized Cost of Electricity (LCOE) and Specific Investment Cost (SIC) for two operation conditions are presented: maximum power output and maximum thermal efficiency. Results showed that R1234ze(Z) achieves the highest net power output (up to 44 kW) when net power output is optimized. Regenerative ORC achieves the highest performance when thermal efficiency is optimized (up to 18%). Simple ORC is the most cost-effective among the studied cycle configurations, requiring a selling price of energy of 0.3 USD/kWh to obtain a payback period of 8 years. According to SIC results, the working fluid R1234ze(Z) exhibits great potential for simple ORC when compared to conventional R245fa

Uncoupling laminar conjugate heat transfer through chebyshev polynomial

The conjugate heat transfer process of cooling a horizontal plate at the leading edge, in steady state condition, was solved considering the fluid flowing in laminar condition and hydro dynamically developed before interacting with a heated plate. The fluid was considered deep enough to allow the growth of a thermal boundary layer with no restrictions. The conservation of mass, momentum and energy equations at the solid and fluid were converted into a non dimensional form. The heated body presents a constant heat flux at the bottom side, and convective heat transfer at the top side. The interface temperature was obtained using the Chebyshev polynomial approximation. In order to verify the results obtained using the Chebyshev polynomial approximation, the results obtained from the analytical solution for the solid, were compared with the results attained with commercial CFD software, FIDAP®. The solution considered the calculation of the local and average heat transfer coefficient, the local and average Nussel t number, the local and average Biot number, and different temperature distributions at the interface

Experimental And Theoretical Analysis Of The Goswami Cycle Operating At Low Temperature Heat Sources

The Goswami cycle is a cycle that combines an ammonia-water vapor absorption cycle and a Rankine cycle for cooling and mechanical power purposes by using thermal heat sources such as solar energy or geothermal steam. In this paper, a theoretical investigation was conducted to determine the performance outputs of the cycle, namely, net mechanical power, cooling, effective first law efficiency and exergy efficiency, for a boiler and an absorber temperature of 85 °C and 35 °C, respectively, and different boiler pressures and ammonia-water concentrations. In addition, an experimental investigation was carried out to verify the predicted trends of theoretical analysis and evaluate the performance of a modified scroll expander. The theoretical analysis showed that maximum effective first law and exergy efficiencies were 7.2% and 45%, respectively. The experimental tests showed that the scroll expander reached a 30-40% of efficiency when boiler temperature was 85 °C and rectifier temperature was 55 °C. Finally, it was obtained that superheated inlet conditions improved the efficiency of the modified expander

Análisis y caracterización de las variables que inciden en el proceso de secado artificial de yuca en un modelo de secador de flujo radial.

En este artículo se presentan los resultados obtenidos en la investigación realizada para establecer la influencia e importancia de las variables cantidad de yuca, relación superficie a volumen del material de los pedazos de yuca, velocidad del ventilador y temperatura del aire de recirculación, en el proceso de secado de yuca en un modelo de secador de flujo radial. La metodología experimental utilizada fue el diseño de experimentos factoriales, la cual, mediante una serie de análisis estadísticos, posibilitó la caracterización del proceso para un tiempo de secado de tres horas y la obtención de un modelo matemático que describe su comportamiento./This article presents the results obtained in the research carried out to establish the influence and importance of the variables: amount of yucca to be dried, the surface area / volume ratio of the yucca pieces, fan speed, and re circulated air temperature, in a yucca drying process performed in a radial flow dryer model. The experimental methodology used was the factorial design, which by mean of a statistical analysis, allowed the characterization of the process in a three hour time frame, and helped to gather enough information to develop a mathematical model that describes the process behavior