Thermal sensation and comfort model for inhomogeneous indoor environments

Aachen / E.ON Energy Research Center, RWTH Aachen Univ. (2011) [Dissertation / PhD Thesis]

Page(s): XIV, 132 S. : Ill., graph. Darst.

Abstract

The subject of this work is thermal comfort in complex non-uniform environments with special regard to aircraft cabins. Under non-uniform conditions, it is difficult to define an acceptable or comfortable range by using only the whole body thermal sensation vote. In complex thermal environments,large thermal differences exist around the occupants. This means that standard comfort models, which consider the human body as one compartment fail in the case of non-uniform environments. Clear evaluations are only possible by considering local effects. The 33 node comfort model (33 NCM) developed for this study relates local thermal sensation and comfort in a psychological model to skin temperatures, which are defined by a physiological model. 16 single body parts are resolved with a subdivision into a core and a skin layer. The local thermal sensation and comfort of the single body parts is transformed into an overall thermal sensation and comfort vote. Since the integrated models for the physiological and psychological part are based on a limited range of experiments with only partly known boundary conditions and the effects of intra- and inter-individual differences, the whole model is calibrated with self-obtained experimental data generated in an automated optimization process. As a result, the optimized set of design parameters is limited to the field of application. The used experimental data reflect the thermal sensation and comfort votes of sitting passengers in an aircraft cabin with a mixing or displacement ventilation system. The universal validity of the underlying model makes it possible, however, to transfer the whole process to any other indoor environment. The book begins with an introduction into the fundamental principles of human physiology and goes on to derive the body’s reactions in terms of thermal sensation and comfort from human physiology and the definition of the human body state. Chapter four presents the various aspects of thermal modelling and developed models. The development of the 33 NCM is based on experiments (chapter five) and numerical flow simulations (chapter six) to collect further information on the environmental conditions. The underlying mathematical models for the 33NCMare explained in chapter seven. Chapter eight defines the optimization process used for calibrating the model. In addition to tests using the author’s own experimental data, the model is validated using data from previous research (chapter nine). Chapter ten demonstrates the application of the 33 NCM as a stand-alone model or in a coupled mode with numerical flow simulations.

Authors

Authors

Streblow, Rita

Advisors

Müller, Dirk

Identifier

  • ISBN: 978-3-942789-00-4
  • URN: urn:nbn:de:hbz:82-opus-35619
  • REPORT NUMBER: RWTH-CONV-125364