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Nowadays, many different research efforts are being conducted to develop personal ventilation system for aircrafts. A numerical CFD study is presented as an example analysis, finding the relationship between the initial jet temperature and mass flow to the local thermal comfort on the head, chest and face. Typical regional airplane cabin geometry was used with two passengers seated. The passengers were modeled with numerical manikins with body and arms. The study first investigated whether the personal ventilation jet has influence on only one of the passengers or if it also affects the other. It was demonstrated that the proposed personal ventilation outlet can influence local thermal comfort with minimum influence on the adjacent passenger. The equivalent temperatures on the head, chest and face were calculated with different initial jet temperatures.

A problem of interest of the aeronautical industry is the positioning of electronic equipment in racks and the associated ventilation system project to guarantee the equipment operational conditions. The relevance of the proper operation of electronic equipment increases considerably when high economical costs, performance reduction and safety are involved. The appropriate operational conditions of the electronic components happen when the working temperature of the equipment installed in the rack is inside a safety project temperature margin. Therefore, the analysis and modelling of heat transfer processes for aircraft rack design becomes mandatory. This paper presents a parametric study considering volumetric and superficial heat generation in electronic equipment within racks in an aircraft. Simulations were performed using the commercial CFD Fluent code and results were compared to experimental data.

Nowadays CFD analysis including virtual manikins is vastly applied to evaluate thermal comfort inside different working environments, such as buildings cars and aircrafts. Inside aircraft cabins, added to the numerical challenges due to geometrical complexity, the available subjective responses used to judge occupant local thermal comfort are usually based on buildings and cars experiments [1]. In the present paper however, it is applied an aircraft based subjective responses to evaluate thermal comfort which was specifically developed using regional jet mock-up experiments. The evaluation for the two approaches will be compared providing insight of the main differences.

There is a worldwide trend for the evaluation of internal thermal comfort in aircraft cabins. Even nowadays one of the major difficulties found is the development and application of a standardized index of internal thermal comfort evaluation in the complex environment of a passenger cabin. The objective of this paper is the CFD model description to evaluate the thermal environment in an aircraft passenger cabin and its results. For this, a digital thermal manikin was developed. Experimental and numerical global heat transfer coefficients were compared. Precision of less than 10% was achieved. In this evaluation five turbulent models were tested. Latter, two numerically calibrated manikins were put into a typical cabin. As a comfort index it was used the equivalent temperature for eighteen body segments. A study of the manikin equivalent temperatures with the aircraft on the ground, in cruise and with low ventilation conditions is presented.

A mathematical simulation model was developed to calculate the cooling loads in a cab. The cooling loads calculations are described: Solar irradiation through glasses, conduction through the body walls and glasses, conduction through motor compartment, fresh air intake/infiltrations, people and equipments. Fields experiments were conducted to evaluate the conduction through walls and glasses and the total cooling load models. Precision less than 5% was gotten between experimental measurements and model results. In the summer situation, studies about the effects of the cab orientation, the time, the external paint and the tint of the glasses in changing the conduction and solar radiation cooling loads, were conducted. Cab orientation and the time can change this cooling loads by 225%. Variation by 30% was gotten from different paints and glasses.

A contract between the Escola Politécnica of the Univeridade Estadual de São Paulo and the Mercedes-Benz do Brasil S/A was set to study the heat sources that act on a cab. This article is a bibliographical review on this topic. In the first part is reviewed how the heat sources mathematical models were developped from 1960 to these days. On the second part is commented and discussed some topics on cab ventilation as: air circulation and distribution pattern external air introduction, air dischange nozzles and outlets displacement, comfort discharging air velocity and temperature, etc…

A mathematical simulation model was developed to calculate the internal and the external temperature of a motor compartment wall with radiant heat exchange of the exhaust system and with convective heat exchange with the compartment inside air. Fields experiments were conducted to evaluate the model with a road bus and a heavy truck. Precision less than 5% was gotten between experimental measurements and model results. The effectiveness of the heat shield was verified numerical and experimentally on a heavy truck.

A mathematical simulation model was developed to calculate the cooling loads in a cab. The cooling loads calculations are described: Solar irradiation through glasses, conduction through the body walls and glasses, conduction through motor compartment, fresh air intake/infiltrations, people and equipments. Fields experiments were conducted to evaluate the conduction through walls and glasses and the total cooling load models. Precision less than 5% was gotten between experimental measurements and model results. In the summer situation, studies about the effects of the cab orientation, the time, the external paint and the tint of the glasses in changing the conduction and solar radiation cooling loads, were conducted. Cab orientation and the time can change this cooling loads by 225%. Variation by 30% was gotten from different paints and glasses.