Development of a simulation model of the heating process in the passenger cabin of a vehicle under low temperature conditions

Introduction. A distinctive feature of working conditions in the Arctic territories is the long period of exposure to low temperatures. Passenger transportation by road is becoming one of the key aspects of ensuring the continuity of the production process. The task of delivering workers to the place of work, moving them between work zones during a work shift is solved by using wheeled vehicles of various categories. One of the most widespread types of wheeled vehicles used to transport workers is the M3 category wheeled vehicles with a capacity of no more than 22 passengers. Ensuring the thermal comfort of vehicle passengers seems to be relevant, since ensuring biophysical compatibility minimizes the risks of cold injury by workers and maintains a high level of performance.Materials and methods. The results of the analysis of the Russian and foreign studies in the direction of ensuring thermal comfort and ensuring biophysical compatibility in confined spaces are presented. The results of computer modelling of the dynamics of microclimate parameters in the passenger cabin of a wheeled vehicle of M3 category with a capacity of no more than 22 passengers are presented.Results. The paper presents the results of theoretical studies, microclimate parameters in the passenger compartment of vehicles, taking into account the breathing of passengers and changes in the gas composition of exhaled air. Theoretical studies of the operation of the heating system of the passenger compartment were carried out, taking into account the refined breathing model of passengers. Distributions of microclimate parameters in the section of the passengercompartment were obtained when using a heating system with one heater; the impact of passengers’ breathing on the parameters of the microclimate in the passenger compartment was assessed.Discussion and conclusion. Based on the numerical solution of the system of heat transfer equations, directions for further research and recommendations are formulated to ensure thermal comfort in the passenger compartment of a wheeled vehicle at low temperatures. The materials of the work may be of interest to specialists involved in the design and ergonomics of wheeled vehicles, labor protection.

Effect of Top Ventilation on Cooling Characteristics of Passenger Cabin

In order to solve the hot soak effect of car during summer parking, the CFD numerical method was used to simulate the cooling law of passenger cabin under different inlet area, inlet velocity and inlet angle at the top vent. From the two dimensions of cooling rate and cooling effect, the influence of top natural ventilation and top forced ventilation on the cooling characteristics of passenger cabin were studied. The results show that under the condition of top natural ventilation, the cabin can reach thermal balance at about 10 min under different vent area conditions, and the cooling rate is the largest when the vent is fully opened, and the minimum temperature can reach about 45 °C within 4 min, which is 10 °C higher than the ambient temperature. Under forced ventilation, the inlet velocity has a great influence on the cooling rate and cooling effect of cabin. When the inlet angle is 90° and the inlet velocity is 5 m / s, the cooling rate is the largest and the cooling effect is the best.

The Air in the Cabin of Passenger Aircraft Is Not as Good As Is Often Assumed - Backgrounds, Possible Solutions and Their Implementation

Fume or smoke events have already been observed on many flights of large passenger aircraft. These events can be explained by sudden failures of seals on the bearings of jet engines, which results in pyrolized engine oil to reach the passenger cabin. But there are also many other ways in which cabin air can be contaminated. Contamination can also be caused by hydraulic or deicing fluid. Pilots, cabin crew and passengers have become ill from such singular events as they themselves report and as confirmed by medical professionals. But even without having ever experienced such a single event, pilots and cabin crew have fallen ill. This could be explained by the small amounts of oil that regularly leak from the seals.

OCULAR PROBLEMS ASSOCIATED WITH AIR TRAVELING

Air transport is the most dynamically developing branch of transport and the number of services provided by civil aviation is increasing from year to year. However, the conditions in the passenger cabin during the flight differ from those on the ground. The aim of this report is to discuss how the changed environment in the cabin affects the visual system, where eye disorders can cause or exacerbate existing ones and in which diseases traveling by air is contraindicated. Air traveling is generally safe for most passengers with eye diseases, but may cause exacerbation of some diseases of the eye and is contraindicated after some vitreoretinal operations and in the case of ischemic changes of the retina and optic nerve.

Concept evaluation of a new aircraft passenger privacy bubble using virtual prototyping: A Human-Centered Design framework

BACKGROUND: The Human-Centered Design methodology advocates VR prototyping, as an effective tool to evaluate concepts in a cost-efficient, time-saving way. It is the question of whether it works in the development of a product intended to increase privacy while flying. OBJECTIVE: The current study aims at the application of virtual reality on the evaluation of a new privacy bubble called PRIVA for the passenger cabin. METHODS: An interactive VR was created and aligned with the HTC VIVE headset. 40 participants took part in the experiment as well as in the post-experiment survey. RESULTS: The concept was in overall, desirable as it was perceived to be more private, comfortable, satisfactory, effective, and appealing to participants compared to the current seat experiences. It was also perceived as more satisfactory with regards to the activities. CONCLUSIONS: The VR was effective, although there are limitations, the product seems promising and should be developed further.

Design of Acoustic Metamaterials for Cabin Noise Reduction and Pressure Sensing in Propfan Aircrafts

This research is about to address the main challenge related to newly emerging airplane engines, namely open rotor (propfan). Though these engines show high efficiency, yet the noise generated is very high. This research focuses on designing a new class of ‘Acoustic Metamaterial’ to overcome the noise reaching the passenger cabin. An acoustic metamaterial is a complex composite structured material that exhibits negative density and negative bulk modulus either individually or simultaneously. The objective of this research is to design an acoustic fuselage using a combination of Negative density acoustic material (NDAM) and Negative bulk modulus acoustic material (NBAM) to reduce the noise transmission into the passenger cabin. Furthermore, the developed acoustic metamaterial structure can be used for pressure sensing application. Based on the literature reviews, experiments pertaining to the combination of NBAM and NDAM are limited. Hence, an integration of both structures is very appealing to be developed. Accordingly, the research will design a combination of two types of Helmholtz resonators (Conventional with one inner membrane and two inner membranes) of negative bulk modulus acoustic metamaterial. This filter can be embedded in a sandwich structure to obtain a new type of cabin wall. Hence the design and development of such acoustic metamaterial are expected to reduce the noise inside the cabin to a minimum. Also, the designed structure will be able to sense pressure at selected locations inside the cabin.