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ispartof: Proceedings of Space Propulsion 2016 ispartof: Space Propulsion 2016 location:Rome, italy status: accepted

International audience; no abstract

Computational fluid dynamics plays an important role in engineering design. To gain insight into solving problems involving complex industrial flows, such as impinging gas-jet systems (IJS), an evaluation of several eddy viscosity models, applied to these IJS has been made. Good agreement with experimental mean values for the field velocities and Nusselt number was obtained, but velocity fluctuations and local values of Nusselt number along the wall disagree with the experiments in some cases. Experiments show a clear relation between the nozzle-to-plate distance and the Nusselt number at the stagnation point. Those trends were only reproduced by some of the numerical experiments. The conclusions of this study are useful in the field of heat transfer predictions in industrial IJS devices, and therefore for its design.

The paper presents the results of simulation of the heat transport in the human tissue by means of 1D numerical model and experimentally obtained data. The model is based on the control volume numerical method with the skin temperature and heat losses to the surrounding as the boundary conditions. The thermodynamical properties of the tissue were taken from the relevant literature. The results obtained by simulation are compared with the data given in lit. [1]. The temperature droop in upper arm tissue of the observed subject is presented graphically, while the temperature distribution on the upper arm surface is given by thermograms. 1. Introduction The thermal comfort of human being is defined with many parameters such as: air temperature and humidity, air velocity and quality, temperatures of the surrounding objects and physical activity. The reaction of the human body to particular situation can be divided in two categories, active and passive. Conscious active reactions are dressing and undressing and unconscious are sweating and shivering. Passive reactions of human body depend on the heat transfer with the surrounding. In the case of thermal unbalance between the body and surrounding the body temperature can increase or decrease. Both situations can be dangerous. The zone of thermal comfort for sedentary humans where mean radiant temperature equals dry bulb temperature and clothing thermal conductance is 10,8 W/(m 2 K) is given on fig. 1. The goal of the research was development of the numerical model by means of which the temperature distribution in the human tissue could be calculated. The boundary conditions for the model are data obtained by thermographic measurements. 2. Thermal balance The thermoregulatory system of human body is maintaining its temperature constant. The energy supplied to the body by food transforms in heat and mechanical work. The metabolic rate is a total energy realised by oxidation in human body per unit time. The heat dissipation from human body to the surrounding takes place through heat and mass transfer. A balance of a human body is given by Eq. (1)