Person: SEVİLGEN, GÖKHAN
Loading...
Email Address
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
SEVİLGEN
First Name
GÖKHAN
Name
4 results
Search Results
Now showing 1 - 4 of 4
Publication The investigation of the effects of spray parameters on the thermal and mechanical properties of 22MnB5 steel during hybrid quenching process(Begell House, 2021-01-01) Sevilgen, Gökhan; Ertan, Rukiye; Bulut, Emre; Öztürk, Ferruh; Eşiyok, Ferdi; Abi, Tuğçe Turan; Alyay, İlhan; SEVİLGEN, GÖKHAN; ERTAN, RUKİYE; BULUT, EMRE; ÖZTÜRK, FERRUH; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/Otomotiv Mühendisliği Bölümü.; 0000-0002-7746-2014; 0000-0001-9159-5000; ABG-3444-2020; KIH-2391-2024; AAG-8907-2021; JIW-7185-2023In this paper, the investigation of the effects of spray parameters on the thermal and mechanical properties of 22MnB5 steel during the hybrid quenching (HQ) process was performed. The HQ method presented in this study includes early removal of hot-stamped parts from the die and transfer to an external multinozzle spray cooling device. The proposed method was developed due to the need for improving disadvantages of the traditional hot stamping process such as complexity of controlling the cooling rate during die quenching by using cooling channels and of providing the reduced tool contact surface temperature after a certain cycle of the hot stamping process. This paper focuses on the temperature distribution and mechanical characteristics of high-strength 22MnB5 steel during the HQ process. Moreover, the methodology developed in this paper can be used to get tailored parts where the cooling rates are locally chosen to achieve structures with graded properties, i.e., to allow local modification of final mechanical properties in order to provide high energy absorption to enhance the crashworthiness of the whole component and thus to improve the vehicle safety performance. The three-dimensional numerical model of spray cooling was also developed by using the computational fluid dynamics (CFD) method to get the suitable process parameters such as spray height and initial blank temperature and to present the detailed heat transfer analysis of hot-stamped parts during the hybrid quenching process.Publication Thermal analysis of different heat pump systems for heating process of electric vehicles(Begell House, 2021-03-05) Bayram, Halil; Sevilgen, Gökhan; SEVİLGEN, GÖKHAN; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/Otomotiv Mühendisliği Bölümü.; 0000-0002-7746-2014; ABG-3444-2020In this paper, three different 1D models of electric vehicle heating, ventilation, and air conditioning (HVAC) system integrated with the vehicle cabin model for heating process were developed. The numerical results were compared in terms of thermal performance to get the desired thermal conditions inside the vehicle cabin. The results of the hybrid heat pump 1D model including both HVAC components and an additional electrical heater showed better thermal performance than the others and it was proposed for the heating process of electric vehicles. At the end of the driving cycle, the average temperature inside the cabin was increased up to about 7 degrees C and 14 degrees C by using the conventional heat pump and innovative heat pump models, respectively, at -5 degrees C ambient temperature and the target temperature cannot be reached. However, under the same conditions, the vehicle cabin could be heated up to about 25 degrees C by using the hybrid heat pump model with a 1-kW electrical heater. In addition, the thermal performance of different heat pump systems can be improved by using electric vehicle thermal management system that allows performing transient simulations for the estimation of the dynamic behavior of system. This study also contributes to decrease of energy usage for HVAC processes that considerably affects the mileage of the vehicle and also life cycle of batteries. These 1D models can be used not only in thermal performance but also can be utilized for thermal comfort conditions of electric vehicles.Publication A new approach for battery thermal management system design based on grey relational analysis and latin hypercube sampling(Elsevier, 2021-09-16) Bulut, Emre; Albak, Emre İsa; Sevilgen, Gökhan; Öztürk, Ferruh; BULUT, EMRE; ALBAK, EMRE İSA; SEVİLGEN, GÖKHAN; ÖZTÜRK, FERRUH; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/Otomotiv Mühendisliği Bölümü; Bursa Uludağ Üniversitesi/Gemlik Asım Kocabıyık Meslek Yüksekokulu/Hibrit ve Elektrikli Araç Teknolojisi; 0000-0001-9159-5000; 0000-0001-9215-0775; 0000-0002-7746-2014; ABG-3444-2020; AAG-8907-2021; I-9483-2017; JCO-2416-2023; FRD-1816-2022A liquid cooling system is an effective type of battery cooling system on which many studies are presented nowadays. In this research, the effects of the mass flow rate and number of channels on the maximum temperature and pressure drop are investigated for multi-channel serpentine cooling plates. A new approach with LHS and GRA is used to obtain the optimum ranges of design parameters to minimize the pressure drop, maximum temperature and to maximize the convective heat transfer coefficient. In this study, the values of the parameters for the numerical modeling are obtained by the experiments. The width and height of the serpentine channel and mass flow rate are chosen as input parameters and the pressure drop, convective heat transfer coefficient and maximum temperature are selected as output parameters. Comparing with the base design, the optimized design provided up to 40.3% decrease in the pressure drop with a penalty of 11.3% decrease in the convective heat transfer coefficient with a slight decrease in the maximum temperature. The proposed approach can be used to design better cooling plates to keep the batteries in safe temperature ranges and to reduce the power consumption by optimizing the pressure drop and maximum temperature values.Publication Dual-separated cooling channel performance evaluation for high-power led Pcb in automotive headlight(Elsevier, 2021-06) Sevilgen, Gökhan; Kılıç, Muhsin; Aktaş, Mehmet; SEVİLGEN, GÖKHAN; KILIÇ, MUHSİN; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/Otomotiv Mühendisliği Bölümü; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/Makine Mühendisliği Bölümü; 0000-0002-7746-2014; 0000-0003-2113-4510; O-2253-2015; ABG-3444-2020In this paper, thermal and hydraulic analysis of a dual-separated cooling channel was performed for the cooling applications of different automotive lighting systems. A single LED and multi-LEDs were considered to evaluate the thermal and hydraulic performance as well as the lighting properties of automotive headlights. The detailed hydraulic analysis was theoretically evaluated for developing laminar flow to get higher thermal performance with less pumping power. The theoretical and simulation results for the dual-separated cooling channel were compared and discussed. Unlike the constant properties were used in the current literature, thermal analysis with temperature-dependent properties was performed to estimate Nusselt number preciously for dual-separated cooling channels. The temperature measurements were also performed in the experimental study to compare the numerical results. The light output parameter of the LEDs depends on junction temperature, it was found that the increase in light output by using a dualseparated cooling channel was about 10% for all cases. Otherwise, higher junction temperature values lead to a reduction in operating efficiency. The top copper surface temperature drop was higher than 50%, and the junction temperature had been reduced by 36% to ensure the desired operating conditions of the automotive lighting system.