Experimental Simulation of the Human Respiration

Abstract

In this paper, we present a new mobile respiration simulation system (RSS), which can be connected to existing thermal manikins. With the objective to simulate the human respiration process as realistic as possible, the system was validated on the basis of literature data and results obtained from human subject tests. The RSS reproduces realistic respiration cycles characterized by a sine wave of a typical normal breathing flow rate. The provided flow rates as well as the breathing frequency – representing the time of inhalation and exhalation – were verified by literature values. Since the new system additionally allows to enrich the exhaled air with carbon dioxide ($\mathrm{CO}_2$), experimental studies addressing the indoor air quality are also feasible. Here, the amount of $\mathrm{CO}_2$ emitted by the RSS corresponds to the average amount of $\mathrm{CO}_2$ exhaled by test persons. In addition, the flow characteristics occurring in a human nose are simulated using a self-developed facial mask, in combination with the new system. The result is a breathing thermal manikin based on a mobile respiration simulation system, which can easily be connected to heated passenger models. Accordingly, the system can be installed at any seat within a passenger compartment. This offers the advantage of individually defining the location of the manikin, which can effortlessly be adapted during a measurement campaign. Therefore, the system especially suitable for studies addressing the performance of ventilation systems in passenger compartments and indoor environments.