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

2021 ◽  
Vol 18 (5) ◽  
pp. 510-523
Author(s):  
D. A. Aleshkov ◽  
M. V. Banket ◽  
M. V. Sukovin

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.

2019 ◽  
Vol 9 (1) ◽  
pp. 121-124
Author(s):  
Florin-Emilian Turcanu ◽  
Ana Diana Ancas ◽  
Mihai Profire ◽  
Marina Verdes ◽  
Marius Costel Balan

Abstract This paper evaluates a static heating system from a church. They are presented in almost every church. Temperature distribution in the church is done in 2d plane. The simulation is presented on a particular example, the Dormition of the Mother of God Church from Jassy, Romania. The heating system had been simulated in FLUENT and the consequences over the interior climate in the church are showed. An important issue is the impact of this system over the artwork, the church being rise in XVIII century.


Author(s):  
I.S. Malakhova ◽  
◽  
T.K. Losik ◽  
O.V. Burmistrova

Abstract. Introduction. Work in low temperatures can lead to both general and local cooling of the human body. Local cooling of the distal parts of the legs can limit the motor activity of the employee even with sufficient thermal insulation of the body general surface. Therefore, the use of an additional heat source in special shoes (autonomous electric heating system (AEHS)) can compensate heat losses in the distal parts of the legs and provide thermal comfort in conditions of low temperatures throughout the work. The purpose of the study: physiological and hygienic assessment of the additional heat sources (AEHS) influence on the thermal insulation of special shoes in conditions of low temperatures. Materials and methods. To assess the heat-protective properties of the special shoes experimental sample with an AEHS, a heat flux density and skin temperature meter ITP-MG 4.03/30 "POTOK" (LLC SKB Stroypribor, Chelyabinsk) was used. The presented sample was tested with the participation of 5 volunteers in three modes of autonomous electric heating in a microclimatic chamber for 60 minutes for each mode separately. The average air temperature in the chamber during the study was 2.5±0.5 °C. Based on the obtained data, the thermal insulation of special shoes with an AEHS was calculated. Results. The thermal insulation of the special shoes experimental sample without electric heating was 0.460±0.013 °C m2/W; and 0.512±0.01 and 0.549±0.01 °C m2/W using the minimum and medium electric heating modes-, respectively, which allows us to recommend the presented sample of special shoes with an autonomous electric heating system for work in a "Special" climatic zone when performing moderate-severity work. The thermal insulation of a special shoes sample with the maximum electric heating mode was 0.615±0.01 °C m2/W, which makes it possible to work with it in the IV climatic zone. Conclusions. The use of an AEHS increases the thermal insulation of special shoes, which provides sufficient protection for the distal parts of the legs, allows to expand the scope of its operation in strict compliance with the work and rest regime and can be a prevention of the occupational diseases development in workers at low temperatures.


2019 ◽  
Vol 23 (1) ◽  
pp. 379-392 ◽  
Author(s):  
Tamara Bajc ◽  
Milos Banjac ◽  
Maja Todorovic ◽  
Zana Stevanovic

The paper presents an experimental analysis of the relationship between local thermal comfort and productivity loss in classrooms. The experimental investigation was performed in a real university classroom during the winter semester in city of Belgrade. Measurements were taken for four scenarios, with different indoor comfort conditions. Variations were made by setting the central heating system on/off, adding an additional heat source to provoke higher indoor temperatures, and measuring the radiant asymmetry impact. Innovative questionnaires were developed especially for the research, in order to investigate students? subjective feelings about local thermal comfort and indoor environmental quality. Local predicted mean vote and predicted percentage dissatisfied indices were calculated using data measured in situ. The results were compared to existing models recommended in literature and European and ASHRAE standards. Student productivity was evaluated using novel tests, designed to fit the purposes of the research. Surveys were conducted for 19 days under different thermal conditions, during lectures in a real classroom, using a sample of 240 productivity test results in total. Using the measured data, new correlations between the predicted mean vote, CO2, personal factor and productivity loss were developed. The research findings imply that local thermal comfort is an important factor that can impact productivity, but the impact of the personal factor is of tremendous importance, together with CO2 concentration in the classroom.


2019 ◽  
Vol 2 (1) ◽  
pp. 29-39 ◽  
Author(s):  
S. G. Konesev ◽  
P. A. Khlyupin

Introduction: the systems of thermal effects on thermo-dependent, viscous and highly viscous liquids under conditions of the Arctic and the Extreme North are considered. Low efficiency and danger of heating systems based on burned hydrocarbons, heated liquids and steam are shown. Electrothermal heating systems used to maintain thermo-dependent fluids in a fluid state are considered. The evaluation of the effectiveness of the application of the most common electrothermal system — heating cables (tapes). The most effective electrothermal system based on induction technologies has been determined. Materials and methods: considered methods of thermal exposure to maintain the fluid properties of thermo-dependent fluids at low extreme temperatures. Results: presents an induction heating system and options for its implementation in the Extreme North and the Arctic. Conclusions: induction heating system to minimize loss of product quality, improve the system performance under changing process conditions, eliminate fire product, to reduce the influence of the human factor.


2019 ◽  
Vol 16 (6) ◽  
pp. 50-59
Author(s):  
O. P. Trubitsina ◽  
V. N. Bashkin

The article is devoted to the consideration of geopolitical challenges for the analysis of geoenvironmental risks (GERs) in the hydrocarbon development of the Arctic territory. Geopolitical risks (GPRs), like GERs, can be transformed into opposite external environment factors of oil and gas industry facilities in the form of additional opportunities or threats, which the authors identify in detail for each type of risk. This is necessary for further development of methodological base of expert methods for GER management in the context of the implementational proposed two-stage model of the GER analysis taking to account GPR for the improvement of effectiveness making decisions to ensure optimal operation of the facility oil and gas industry and minimize the impact on the environment in the geopolitical conditions of the Arctic.The authors declare no conflict of interest


2017 ◽  
Vol 8 (5) ◽  
pp. 221
Author(s):  
Sugiono Sugiono ◽  
Suluh E. Swara ◽  
Wisnu Wijanarko ◽  
Dwi H. Sulistyarini

Author(s):  
Zulpadli Zulpadli

This paper briefly and through theoretical studies will discuss simply the problems formulated, the impact of globalization on Character education in Indonesia, as well as the paradigm of PKN learning and Character education challenges for the younger generation. It is on the ground by the declining awareness and moral values, as well as to increase the values of the characters seen in the young generations. Civic education in Indonesia has been running throughout the history of Indonesian independence, and has gone through various stages and arms, it certainly demands greater hard work of teachers to be able to increase the values of Pancasila and love of the homeland, and practice the character values which is based on the noble values of Indonesian culture into Indonesian youth.


Author(s):  
S. A. Gorbanev ◽  
S. A. Syurin ◽  
N. M. Frolova

Introduction. Due to the impact of adverse working conditions and climate, workers in coal-mining enterprises in the Arctic are at increased risk of occupational diseases (OD).The aim of the study was to study the working conditions, causes, structure and prevalence of occupational diseases in miners of coal mines in the Arctic.Materials and methods. Th e data of social and hygienic monitoring “Working conditions and occupational morbidity” of the population of Vorkuta and Chukotka Autonomous District in 2007–2017 are studied.Results. It was established that in 2007–2017 years, 2,296 ODs were diagnosed for the first time in 1851 coal mines, mainly in the drifters, clearing face miners, repairmen and machinists of mining excavating machines. Most often, the ODs occurred when exposed to the severity of labor, fibrogenic aerosols and hand-arm vibration. The development of professional pathology in 98% of cases was due to design flaws of machines and mechanisms, as well as imperfections of workplaces and technological processes. Diseases of the musculoskeletal system (36.2%), respiratory organs (28.9%) and nervous system (22.5%) prevailed in the structure of professional pathology of miners of coal mines. Among the three most common nosological forms of OD were radiculopathy (32.1%), chronic bronchitis (27.7%) and mono-polyneuropathy (15.4%). In 2017, coal miners in the Arctic had a professional morbidity rate of 2.82 times higher than the national rates for coal mining.Conclusions. To preserve the health of miners of coal mining enterprises, technical measures to improve working conditions and medical interventions aimed at increasing the body’s resistance to the effects of harmful production and climatic factors are necessary.


Author(s):  
Sergei Soldatenko ◽  
Sergei Soldatenko ◽  
Genrikh Alekseev ◽  
Genrikh Alekseev ◽  
Alexander Danilov ◽  
...  

Every aspect of human operations faces a wide range of risks, some of which can cause serious consequences. By the start of 21st century, mankind has recognized a new class of risks posed by climate change. It is obvious, that the global climate is changing, and will continue to change, in ways that affect the planning and day to day operations of businesses, government agencies and other organizations and institutions. The manifestations of climate change include but not limited to rising sea levels, increasing temperature, flooding, melting polar sea ice, adverse weather events (e.g. heatwaves, drought, and storms) and a rise in related problems (e.g. health and environmental). Assessing and managing climate risks represent one of the most challenging issues of today and for the future. The purpose of the risk modeling system discussed in this paper is to provide a framework and methodology to quantify risks caused by climate change, to facilitate estimates of the impact of climate change on various spheres of human activities and to compare eventual adaptation and risk mitigation strategies. The system integrates both physical climate system and economic models together with knowledge-based subsystem, which can help support proactive risk management. System structure and its main components are considered. Special attention is paid to climate risk assessment, management and hedging in the Arctic coastal areas.


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