CFD simulation of a cabin thermal environment with and without human body – thermal comfort evaluation

Abstract

Nowadays, thermal comfort became one of the criteria in choosing a vehicle. In last decades time spent by people in vehicles had risen substantially. During each trip, thermal comfort must to be ensured for a good psychological and physical state of the passengers. Also, a comfortable environment leads to a higher power concentration of the driver thereby to a safe trip for vehicle occupants and for all traffic participants. The present study numerically investigated the effect of human body sited in the driver's place, over the air velocity distribution and over the thermal comfort in a passenger compartment. CFD simulations were made with different angles of the left inlet grill, in both cases, with and without driver presence. In majority of the actual vehicles environment studies, are made without consideration of human body geometry, in this case, the results precision can be affected. The results show that the presence of human body, lead to global changing of the whole flow pattern inside the vehicular cabin. Also, the locations of the maximum velocities are changing with the angle of the guiding vanes. The thermal comfort PMV/PPD indexes were calculated for each case. The presence of human body leads to a more comfortable environment.

Design of a Small-Scale Experimental Model of the International Space Station Crew Quarters for a PIV Flow Field Study

“…4). The dimensions of the human body model were chosen to fit the scale of our human body numerical models and keeping the proportions of one thermal manikin that was developed in our team [7] [8].…”

Theoretical studies of the heating system in the vehicle compartment during passenger transportation taking into account breathing under conditions of low temperatures

“…The development of microclimate regulation systems is presented in papers [8,21,27,28], and the assessment of their performance by such indicators as energy consumption, thermal comfort and air quality is presented in papers [6,12,13,29,30,31,32,33]. Theoretical studies of microclimate regulation systems and microclimate effect on humans are based on computer models described in papers [3,5,7,9,10,25,27,28,29,33]. The papers [35,36] provide a comparative analysis and assessment of the possibilities of various implementations of mathematical models of gas thermodynamics on computers.…”

“…The assessment of arising subjective sensations of passengers under certain microclimatic conditions is presented in papers [7,17,26]. Different schemes of microclimate regulation and thermal comfort provision for different types of wheeled vehicles have been studied in papers [9,20,29]. Assessment of changes in microclimate parameters in time and various driving conditions of a wheeled vehicle has been performed in papers [11,15,16,19].…”

CFD Modelling of The Airflow in The Driver's Cabin of a Modern Rail Vehicle

“…Based on the literature review, it was found out that researchers focused their attention on motorization and HVAC systems mainly for automobile cabins, for example [2], [3], [4], [5], [6], [7]. For the railway industry, CFD simulation tend to focus on airflow simulations in carriages, for example [8], [9].…”

“…Otherwise, drivers can become fatigued easily. A comfortable vehicular climate not only helps to reduce the driver stress but also guarantees good visibility by avoiding the fog phenomenon, and thus contributing to safer driving [5]. It is also important due to the fact that rail freight transport is widely used and prevalent in many countries around the world.…”