Thermal comfort formation of the bus interior depending on the power unit layout
Keywords:thermal comfort, ASHRAE Standard, EN ISO 7730, HVAC, heating, ventilation and air conditioning systems, engine placement, power unit layout, driver interior, passenger compartment, PMV, PPD indices
Energy consumption and thermal comfort are among the issues that research engineers of heating, ventilation and air conditioning systems deal with when investigating the most feasible solutions for their implementation. Existing methods of thermal comfort assessment are not optimized in two important and interrelated aspects: achieving thermal comfort (a) at the lowest possible energy consumption (b). Thermal comfort is situationally achieved when occupants perceive the ambient temperature, humidity, air movement and thermal radiation as ideal and do not prefer warmer or colder air or a different humidity level. Thermal comfort is defined by ASHRAE Standard 55 as a subjective concept characterized by the sum of sensations that create physical and mental well-being in a person. That is, he/she is in a state in which he/she feels comfortable and does not need to change one or more environmental parameters. Many studies have been conducted according to the international standards for thermal comfort in vehicles. The presence of a large number of people in the bus leads to a deterioration of the air quality in its interior. The loss of quality is mainly caused by gases resulting from breathing and other organic particles. The presence of moisture, combustion products, particles can also reduce the air quality in the interior. Air quality is affected by the design features of heating, ventilation and air conditioning systems, which largely depend on the location of the power unit, which is the subject of the research. The influence of the bus engine layout is analysed in the presented work: for the rear-engine layout, the location of the engine vertically in the interior and other cases are also considered. Special fans are installed in the engine compartment to remove heat emitted by the engine.
Haller G. (2006). Thermal Comfort in Rail Vehicles. RTA Rail Tec Arsenal Fahrzeugversuchsanlage GmbH, Vienna.
P.O. Fanger, Proposed Nordic standard for ventilation and thermal comfort, in: in Proc. Int. Conf. On Building Energy Managment, 1980.
H. Nilsson, I. Holmér, M. Bohm, O. Norén, Equivalent temperature and thermal sensation - Comparison with subjective responses, in: Comfort in the automotive industry- Recent development and achievements, Bologna, Italy, 1997, pp. 157-162.
H.O. Nilsson, I. Holmér, Definitions and Measurements of Equivalent Temperature, European commission cost contract no smt4-ct95-2017.
ISO, Ergonomics of the thermal environment - Evaluation of thermal environments in vehicles: Principles and methods for assessment of thermal stress, in: ISO 14505-1:2007, 2007.
M. Kilic, S.M. Akyol, Experimental investigation of termal confrot and air qualitu in an automobile interior during cooling period, Heat MassTransfer, 48 (2012) 1375-1384.
B. Torregrosa-Jaime, F. Bjurling, J.M. Corberan, F.D. Sciullo, J. Paya, Transient thermal model of a vehicle's interior validated under variable ambient conditions, Applied Thermal Engineering, 75 (2015) 45-53.
S. Sepehr, M. Dehghandokht, A. Fartaj, Temperature control of a interior in an automobile using thermal modeling and fuzzy controller, Applied Energy, (2012) 860–868.
M.S. Oh, J.H. Ahn, D.W. Kim, D.S. Jang, Y. Kim, Thermal comfort and energy saving in a vehicle compartment using a localized air-conditioning system, Applied Energy, 133 (2014) 14-21.
P. Dancaa, A. Vartiresa, A. Dogeanu. An overview of current methods for thermal comfort assessment in vehicle interior Energy Procedia 85 (2016) 162 – 169.
D.W. Lee, Impact of a three-dimensional air-conditioning system on thermal comfort: An experimental study, Int.J Automot. Technol., 16 (2015) 411-416.
I.Sarna, A.Palmowska. Modelling of the airflow in the passenger coach. Architecture Civil Engineering Enviroment, No 4, 2019, рр.125-132
Şaban Ünal. An experimental study on a bus air conditioner to determine its conformity to design and comfort conditions. Journal of thermal engineering, 2017, No 1, рр. 1089-1101
Horbai O.Z. Mitsnist ta pasyvna bezpeka avtobusnykh kuzoviv: monohrafiia / O.Z. Horbai, K.E. Holenko, L.V. Krainyk. – Lviv: Vydavnytstvo Lvivskoi politekhniky., 2013. – 276 s.
O. A. Tryhub, V. V. Zahubynoha, L. A. Tarandushka. Vyznachennia produktyvnosti nahnitaiuchykh ventyliatoriv systemy avtomatychnoi ventyliatsii kuzova avtomobilia. Visnyk Vinnytskoho politekhnichnoho instytutu, 2018, №4. – S. 95-102.
O. Horbay, Y. Voichyshyn, E. Yakovenko. (2020). Study of the heating system of a city bus. International symposium of education and values, 4, p. 70.
Özgur Ekici and Gökhan Güney. (2017). Experimantal and numerical investigations of heating in a bus interior under transient state conditions. Computational methods and experimental measurements XVIII. Transactions on engineering sciences, 118, рp. 49-59.
Jhan Piero Rojas, Guillermo Valencia Ochoa, Jorge Duarte Forero. CFD Analysis of Swirl Effect in a Diesel Engine Using OpenFOAM. 10.15866/iremos.v13i1.18372, 2020, Vol 13 (1), pp. 8
Zhang, T., Yin, S. & Wang, S., An under-aisle air distribution system facilitating humidification of commercial aircraft interiors. Building and Environment, 45, pp. 907–915, 2010
Dolinskiy A.A., Draganov B.Kh. Optimizatsiya energeticheskikh sistem na osnove teoretiko-grafovykh postroyeniy [Optimization of energy systems based on graph-theoretic constructions]. Kiev: Akademperiodika, 2013. 67 p.
Zhang, T., Li, P. & Wang, S., A personal air distribution system with air terminals embedded in chair armrests on commercial airplanes. Building and Environment, 47(1), pp. 89–99, 2012.
Zhang, T. & Chen, Q., Novel air distribution systems for commercial aircraft interiors. Building and Environment, 42, pp. 1675–1684, 2007.