Computational fluid dynamics has become an important tool in the prediction of thermal comfort in occupied spaces. Despite its ability to predict temperature and velocity fields, it is more difficult to evaluate the degree of thermal comfort experienced by an occupant. This article describes the construction of a new numerical thermal manikin, with new comfort evaluation methods based on data from thermal manikin measurements as well as subjective results from several hundred experiments. The level of thermal comfort is highly dependent on the local environment. Human beings respond differently to local heat transfer in different parts of their bodies. It is suggested for that reason that local results from manikins should be presented in new clothing independent comfort zone diagrams. The research presented in here is intended to be used to evaluate system solutions that provide improved thermal climate in many different everyday situations, e.g. all types of buildings and vehicles.

 It has always been valuable to be able to make early decisions in thermal climate investigations. The development of virtual thermal manikins (VTM) and computer simulated persons (CSP) has become an important complement to traditional evaluation of the thermal environment. This paper describes how to build a VTM within a commercial computational fluid dynamics code (CFD). The methods are based on human experiments and real thermal manikin measurements.

Unfortunately, too few of the theories behind thermal manikin simulations are available in the public domain. Many researchers and companies still use several in-house codes for all or essential parts of their calculations. This paper provides information on how to build the geometry of the manikin in three different commercial CFD codes (CFX (R), Star-CD (R) and Fluent (R)). More information and descriptions are also given on how to connect the VTM to the CFD calculations and make the system interact in real time throughout the full iteration process.

Increasing demand for a comfortable cabin environment makes it necessary, as early as the construction phase, to estimate what effect different factors will have on the driver and passenger. Full-scale measurements and numerical simulations have been carried out in order to investigate how well computational fluid dynamics (CFD) and thermal manikins are able to predict the perceived thermal climate. The heat loss from real or virtual manikins interacts with the environment around the body, as well as thermal interaction with windows; ventilation and seat are influencing the manikins. When manikin heat loss is linked to human thermal sensations in new comfort zone diagrams, the local as well as total thermal situation can be clearly presented. Simulations of this type will enable engineers to make better decisions and early predictions in the design and construction process, improving the thermal comfort in the vehicle environment.

Det är nu aktuellt att göra simuleringar av energiförbrukning och inomhusmiljö för att snabbt ge de effektivaste förslagen på energisparåtgärder. Med verkliga och virtuella termiska manikiner kan man undersöka hur människor kommer att uppleva de olika klimatsituationerna redan innan de uppstår.

Termiska manikiner är formade som människokroppen. De registrerar värmeförluster över hela sin yta i alla riktningar samtidigt, exakt som människor. Genom att bestämma storleken på värmeavgivningen kan en klimatbedömning göras för såväl enskilda kroppsdelar som för hela kroppen. Precis som för människor påverkar kläderna resultatet av mätningen. Med mindre och tunnare kläder blir mätdockan mer känslig för termisk påverkan från omgivningen. Det är därför viktigt att beskriva vilka kläder man använder och att använda komfortzondiagram vid utvärderingen av resultaten.