• 항공우주시스템공학회지
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• 제2권2호
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• pp.46-50
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• 2008

Aerodynamic characteristics, such as drag and lift, play an important role in automobile design under certain speed conditions. Such characteristics are essential to design an automobile since they are directly related to automobile's performance such as passenger safety and fuel consumption. There is a huge demand for the automobile to have safe performance at high speed. Reduction in drag is also important and it could lead to the solution of air flow induced noise and dust problems. The objective of this research is to find out the aerodynamic differences between conventional side mirror and a modified one using CFD. Although drag generated around a side mirror is only about 7% of the total drag when a car runs, it is very closely related to driver's field of vision and noise generation. CFD simulation of the flowfield around a car side-view mirror was performed using a commercial code; Gambit and FLUENT.

• 항공우주시스템공학회지
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• 제4권2호
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• pp.10-15
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• 2010

Aerodynamic noise is becoming the major source of annoyance for modern cars recently and is caused by many different noise sources in a car. Appropriate CFD technologies, therefore, have been developed to resolve the noise problems related with aerodynamics. It is necessary for designers to fully understand the relationship between vehicle aerodynamics and wind noise acoustics. In this study, we simulate the flow fields around two different shapes of side mirror models of passenger car and analyze the noise phenomena around one side mirror model that has lower drag than the other model using Fluent 6.3.

• 항공우주시스템공학회지
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• 제3권4호
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• pp.1-6
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• 2009

Aerodynamic noise is becoming the major source of annoyance for modern cars recently and is caused by many different noise sources in a car. Appropriate CFD technologies, therefore, have been developed to resolve the noise problems related with aerodynamics. It is necessary for designers to fully understand the relationship between vehicle aerodynamics and wind noise acoustics. In this study, we simulate the flow fields around two different shapes of side mirror models of passenger car and analyze the noise phenomena around one side mirror model that has lower drag than the other model using Fluent 6.3.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2573-2578
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• 2007

In order to investigate the vortex body frame interaction around the side mirror of a passenger car, velocity vector fields in the wake, pressure distributions and boundary layer flows over both the mirror surface and the mirror housing, have been measured by several experimental tools. It was resulted that only within an half downstream distance of the mirror span there appears the recirculation zone, and also found that vortex trail towards to the driver side window between A and B pillars, making the acoustic noise and vibration. Wake vortex rolls up after this recirculating zone and makes the trail of the vortex center towards the driver side window, which was also confirmed by measurements of wake velocity vectors in the vertical sections of the trail and visualization over the side mirror surfaces as well. It was also observed that total pressure distribution over the mirror surface has the minimum peak near the lower tip region which can be considered as the origin of the vortex center. It can be concluded that the geometrical modification of the lower tip and the upper root area of the mirror housing is the key to control the wake vortex.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1998년도 춘계 학술대회논문집
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• pp.99-109
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• 1998

This paper describes the analysis of flow and aeroacoustic field around a car-like body. The governing equations, 3-D unsteady incompressible Navier-Stokes equations, are solved with the iterative time marching scheme. The Chimera grid technique has been applied to efficiently simulate the flow around the side-view mirror, After the flow field analysis has been converged, the aerodynamic noise analysis of the side-view mirror has been performed by solving Ffowcs Williams and Hawkings equation. From the present numerical simulation, the A- and C-pillar vortex are evidently shown and the aerodynamic noise level induced by the side-view mirror is predicted to about 100dB.

• 한국자동차공학회논문집
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• 제20권5호
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• pp.26-35
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• 2012

This paper investigates the influence on the aerodynamic performance of a passenger cruising very fast by some specific car body parts such as side mirrors, wheel arches and wheels designed hardly regarding aerodynamics. The magnitude of the contribution of each part is analyzed via on the CFD simulations. YF SONATA, a sedan of Hyundai Motors Company, plays a major role as the baseline car in this research, representing all passenger car. The CFD analysis condition consists of 6 different cases depending on whether each part exists or not. According to the CFD results, there were confirmed that additionally to the body parts' own drag, the car body went through somewhat the consequential increment of the drag by them. Among the 3 parts, wheel is the magnate that not only has the maximal drag but drives the drag of the passenger car to increase most steeply and the next is the side mirror.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.7-7
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• 2000

This paper describes a mirror control system that can adjust the location of side and room mirror of the vehicle automatically using 3D coordinates to monitor the location of driver's eyes. Through analysis of the image inputted by two B/W CCD camera and infrared lamps installed on top of the driver's dashboard, we can estimate the values of 3D coordinate of the driver's eyes. Using these values, this system can determine the absolute position of each mirror and activate each actuator to the appropriate position. The stereo vision system can detect the driver's eyes whether it is day or night by virtue of infrared Lamps. We have tested this system using 10 drivers who drive a car currently, and most of the drivers were satisfied with the convenience of this system.

• 한국융합학회논문지
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• 제10권9호
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• pp.161-166
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• 2019

본 연구에서는 A, B, C 3가지 자동차 사이드미러 모델들에 있어서의 공기 저항으로 인한 유동을 분석을 함으로서 다양한 사이드미러들 주위에서의 흐름을 연구한다. 모델 A는 사각형 모양의 사이드미러이고, 모델 B는 삼각형 모양의 사이드미러, 모델 C은 타원형 모양의 사이드미러이다. 자동차의 사이드미러의 설계를 변경함으로서 운전 시 좀 더 사이드미러의 공기저항을 줄여서 약간의 자동차의 동력을 감소시킬 수 있다. 해석 결과로서, 사이드미러에 대한 공기저항의 압력이 클수록 공기 유동속도가 큰 것을 볼 수 있었다. 그러므로 공기저항의 압력이 작을수록 유동속도가 작고 공기가 더 잘 유통된다고 판단된다. 그러므로 Model B가 가장 좋은 Model이라는 것을 확인할 수 있다. 본 연구결과를 토대로 얻은 자동차 사이드 미러의 설계데이터를 활용함으로서 실생활에서의 자동차 운전시에 그 미적 감각을 나타낼 수 있다.

• 한국항해항만학회지
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• 제32권10호
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• pp.793-798
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• 2008

이 논문은 차량 사이드 미러용 고감도 RFID 태그 안테나의 설계에 대해 나타내었다 제안된 태그 안테나($154\;mm{\times}66\;mm{\times}1;mm$)는 900 MHz에서 공진하며 690 MHz($490\;MHz{\sim}1180\;MHz$)의 넓은 대역폭을 가진다. 태그 안테나의 측정된 이득과 인식거리는 각각 5.8 dBd와 10 m 이다. 차체를 포함한 사이드미러 내부에 위치한 제안된 태그 안테나의 방사패턴과 인식거리가 전파암실에서 측정되었다. $90^{\circ}$근방에서의 인식거리는 차체가 없는 제안된 안테나의 인식거리와의 비교로부터 약 1.5 m 확장된 것을 확인하였다. 제안된 태그안테나의 우수한 성능이 상용 태그안테나의 측정된 결과들과의 비교에 의해 관측되고 입증되었다.

• International Journal of Automotive Technology
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• 제5권4호
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• pp.277-285
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• 2004

This paper describes an intelligent mirror adjustment system that rotates a pair of side mirrors and the room mirror of a car to the optimal position for a driver by using the location of the driver's pupils. A stereo vision system measures the three-dimensional coordinates of a pair of pupils by analyzing the input images of stereo B/W CCD cameras mounted on the instrument panel. This system determines the position angle of each mirror on the basis of information about the location of the pupils and rotates each mirror to the appropriate position by mirror actuators. The vision system can detect the driver's pupils regardless of whether it is daytime or nighttime by virtue of an infrared light source. Information about the pair of nostrils is used to improve the correctness of pupil detection. This system can adjust side mirrors and the room mirror automatically and rapidly by a simple interface regardless of driver replacement or driver's posture. Experiment has shown this to be a new mirror adjustment system that can make up for the weak points of previous mirror adjustment systems.