Yazar "Bacak, Aykut" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • [ X ]
    Öğe
    A comparison of heating and cooling systems having radiant and ventilation systems regarding thermal comfort
    (Springer, 2024) Rahmanparast, Amir; Bacak, Aykut; Camci, Muhammet; Karakoyun, Yakup; Acikgoz, Ozgen; Dalkilic, Ahmet Selim
    Thermal comfort is crucial for indoor environmental quality, impacting occupant well-being and intellectual productivity. Despite the widespread use of HVAC technologies in residential and commercial buildings, there is growing awareness of thermal comfort, leading to more studies on this issue. According to international publication indexes nearly 60% of publications belongs to the categories of construction building technology, energy fuels, and civil engineering. It should also be noted that 40% of world energy consumption pertains to construction sector. In this context, radiant cooling and heating systems come forward with their low exergy destruction rates pointing out the potential to be energy-efficient due to their higher and lower operation temperatures. Displacement ventilation, with its low heating and cooling capacity, has not gained widespread preference. However, the increasing consciousness of global warming and energy efficiency, along with the fear of airborne virus contamination, views stand-alone or hybrid applications of radiant heating/cooling and displacement ventilation as potential future solutions. This review study investigates the impact of radiant heating/cooling and ventilation types, mixing, and displacement on thermal comfort performance, focusing on factors affecting thermal comfort in trending radiant cooling and heating applications like radiant walls, ceilings, and floors. The study emphasizes the importance of considering occupant preferences, building characteristics, and energy efficiency when choosing the most suitable heating and cooling systems for different indoor environments. Stand-alone and hybrid applications of radiant heating/cooling and displacement systems can enhance thermal comfort performance, with the exception of specific cases requiring a high thermal load or ventilation rate.
  • [ X ]
    Öğe
    Novel air duct designs to estimate the windshield demisting issue for a commercial vehicle
    (Sage Publications Ltd, 2024) Akgunlu, Safak; Ozcan, Onur; Bacak, Aykut; Gonul, Alisan; Taner, Tolga; Dalkilic, Ahmet Selim
    This study is about the fog on the windshields of passenger buses because it makes it hard for drivers to see, which is dangerous. The goal of the research is to come up with an effective way to spread the produced mist. According to the study, the air duct design, which is connected to the car's defroster and defrosting system by Kraft hoses, has to be upgraded. The analysis identifies areas in which the current air duct design might be enhanced and then makes design modifications to create a superior design. By conducting climatic chamber experiments on a vehicle equipped with the first air duct design and tracking the actual air velocity values at the nozzle tips, the success of the new technique is assessed. The boundary conditions for the analysis are the observed values. The study involves the utilization of a commercially available software package to conduct investigations on both the original and modified air duct designs. The software package employs a k-epsilon turbulence model that is known to produce reliable results. The data demonstrate that the adjustments made in light of the comparison produced beneficial effects. The maximum air velocities were increased by 23%, while the pressure loss values of the left and right fans were reduced by 2.5% and 2.9%, respectively, due to the modification of the air duct. Significant energy was saved because of the decrease in fan pressure loss, which led to decreases in the power consumption of the left and right fans of 4.2% and 4.7%, respectively. This comparison shows that the newly built air ducts actually increased the flow rate at the system's fan outlets by 40%.