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Contaminant transport in the aircraft cabin became one of the most vital issues that should be concerned; because there are over 4.6 billion passengers choose travelling by aircrafts, as they are safe, comfortable, and fast. In addition, aircrafts manufacturers aim to produce large aircrafts that are able to contain the highest number of passengers. Airborne diseases, for example, SARS and Influenza are considered the most fatal diseases, which can transport in the cabin rapidly, due to the large number of particles or droplets in one cough or sneeze as well as the velocity of these particles, as a consequence these characteristics, airborne pathogens such as cough and sneeze can spread and reach great number of passengers at one time. This study shows the result of simulation of cough droplets that produced from an infected moving passenger using computational fluid dynamics simulation (CFD) and dynamics mesh and discrete phase models in ANSYS FLUENT program, also it reveals the effects of these produced droplets on the other passengers inside the cabin. The results reveals that, cough droplet that produced during the movement of the passenger are extremely detrimental, as it could spread to a distance more than 4 meters along the cabin, moreover, it affected too many passengers in the cabin. [ABSTRACT FROM AUTHOR]

Thermal comfort in automobile cabin can affect drivers and passenger's health, performance and comfort. Due to spatial and temporal variation of state variables and boundary conditions in the automobile cabin, the heating, ventilating and air-conditioning (HVAC) does not have to be designed to provide a uniform environment, especially because of individual differences regarding to physiological and psychological response, clothing insulation, activity, air temperature and air movement preference, etc. The main objective of this research is to study the air flow regimes and thermal comfort in automobile cabin using computational fluid dynamics (CFD) software. For this purpose, the CFD software from ANSYS Inc., called FLUENT 17.2, is employed. In which the solar load model is embedded s2s (surface to surface) as a solar radiation model. The CFD modeling techniques solved the continuity, momentum and energy conservation equations in addition to standard k - e model equations for turbulence closure. Meshing is processed around 4.0 million unstructured tetra-elements approximately. The performance of the air conditioning system is characterized by airflow regimes (air temperature, air velocity, relative humidity, PMV and PPD contours), the present work is focus on the effect of air terminal shape of Hvac system, two configurations are used case (1) and case (2). Case (1) is the existing design of air terminals of the HVAC system of the selected car (Skoda Superb), the air terminals are in rectangular shape. While case (2) are in circle shape. [ABSTRACT FROM AUTHOR]

This paper is devoted to critically analyze the air distribution, thermal patterns and thermal comfort parameters in an air-conditioned enclosure. A computational fluid dynamics model is developed to examine the air flow characteristics of a room with different supply air diffusers at different blade angles. The work focuses on airflow patterns, thermal behavior in the room where few number of occupants. As an input to the full-scale 3-D room model, a 3-D air supply diffuser is numerically modeled to supply air at different directions into the room. Air distribution effect on thermal comfort parameters was investigated depending on changing the air supply diffusers angels. The thermal comfort predictions through this work were based on the PMV (Predicted Mean Vote) model and the PPD (Percentage People Dissatisfied) model, the PMV and PPD were estimated using Fanger's model. [ABSTRACT FROM AUTHOR]

A computational fluid dynamics model is developed to examine the air flow characteristics of a room with different supply air diffusers. The paper is devoted to numerically investigate the influence of location and number of air supply and extracts openings on air flow properties in a typical seating room. The work focuses on air flow patterns, thermal behavior in the room where few number of occupants. As an input to the full-scale 3-D room model, a 2-D air supply diffuser model that supplies direction and magnitude of air flow into the room is developed. Air distribution effect on thermal comfort parameters was investigated depending on changing the air supply diffusers type, angels and velocity. Air supply diffusers locations and number were also investigated. The pre-processor Gambit is used to create the geometric model with parametric features. Commercially available simulation software "Fluent 6.3" is incorporated to solve the differential equations governing the conservation of mass, three momentum and energy in the processing of air flow distribution. Turbulence effects of the flow are represented by the well developed two equation turbulence model. In this paper work, the so-called standard k-ε turbulence model, one of the most widespread turbulence models for industrial applications, was utilized. Basic parameters included in this work are air dry bulb temperature, air velocity, relative humidity and turbulence parameters are used for numerical predictions of indoor air distribution and thermal comfort. The thermal comfort predictions through this work were based on the PMV (Predicted Mean Vote) model and the PPD (Percentage People Dissatisfied) model, the PMV and PPD were estimated using Fanger's model. [ABSTRACT FROM AUTHOR]

In this paper, three dimensional model of the subway station was built, a mathematical model was developed based on the standard κ-[variant_greek_epsilon] turbulence model, and computational fluid dynamics (CFD) simulations for the air conditioning systems were performed to clarify the conditions of the temperature fields. Comparisons were made between different cases of air-conditioning with varying passengers densities showing the degree of human comfort within the space in each case. Commercially available simulation software 'Fluent 6.3' is incorporated to solve conservation of mass, momentum and energy in the processing of air distribution, and to analyze turbulence affection combined heat transfer on air distribution. In this thesis work, the so-called standard κ-[variant_greek_epsilon] turbulence model, one of the most widespread turbulence models for industrial applications, was utilized. Basic parameters included in this work are air temperature, air velocity, relative humidity and turbulence parameters are used for numerical prediction of indoor air distribution. [ABSTRACT FROM AUTHOR]