• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2010년도 제35회 추계학술대회논문집
• /
• pp.410-415
• /
• 2010

제트연료변경에 따른 엔진 운용 특성 변화를 살펴보기 위해 JP-8 연료와 JP-S 연료를 사용하여 소형터보제트엔진의 지상시험 및 고도시험을 수행하였다. 비중이 18% 높은 JP-S 연료에 대한 연료조절 시스템 특성은 동일 연료공급명령에 대한 실 연료공급량이 JP-8 연료보다 8% 많이 공급되었다. 시동 특성은 연료조절시스템의 명령 대비 공급량의 차이로 인한 점화시점 및 엔진 회전수 가속율 등의 변화를 제외하고는 유사한 특성을 보였다. 정상상태 성능 특성은 순 추력의 일부 구간을 제외하고는 순추력과 공기유량, 배기가스온도 등 대부분의 엔진 성능 변수가 1% 이내로 유사하였으나 연료소모량만은 연료의 발열량 차이로 인해 최대 5 %이상 차이가 발생하였다. 이를 동일 추력 대비 비 연료소모율로 비교할 때 지상시험에서는 약 1.1~2.6 %, 고공환경시험에서는 5 % 이상 차이가 발생하였다.

• 동력기계공학회지
• /
• 제21권6호
• /
• pp.46-55
• /
• 2017

Due to the arise of natural disasters caused by global warming, consumers have more interest in the fuel efficiency of their vehicles, and fuel efficiency became an important factor in comparing vehicles. In this market situation, methods to measure fuel efficiency has become one of the main interests of vehicle related organizations and laboratories, and the current method to measure fuel efficiency is to follow the notification established by the ministry of trade, industry and energy, ministry of environment, and the ministry of land, infrastructure and transport. In this study, we analyze the influence of vehicle fuel efficiency according to test temperature and cooling fan condition which have the possibility to cause difference in fuel efficiency. The analysis results of the influence of the fuel efficiency according to the test temperature, the difference of the fuel efficiency of the test temperature ($21{\sim}29^{\circ}C$) within the allowable range of the notification showed a maximum difference of 2.9%. Therefore, it is necessary to consider the introduction of a test method that permits only the temperature change based on the reference point as the allowable range even in the test within the allowable range. The analysis of the influence of the fuel efficiency according to the cooling method showed no significant effect, and it seems reasonable to maintain the test method of the current notification.

• 오토저널
• /
• 제9권1호
• /
• pp.57-68
• /
• 1987

The driving pattern was studied in Seoul along nineteen representative routes using a test car equipped with all the instruments required for recording traffic flow and measuring fuel consumption. Speed histories, gear shift points, instantaneous fuel consumption rates, etc. were recorded and the data were anlyzed to determine the traffic characteristics for Seoul. The Seoul-14 Mode has been developed to simulated actual driving conditions in Seoul with respect to fuel consumption. The average speed of the Seoul-14 Mode is 30.1 Km/h and the Mode length is 11.94 Km.

• Journal of Biosystems Engineering
• /
• 제35권2호
• /
• pp.77-84
• /
• 2010

In this study, we tried to predict tractor power output, fuel consumption rate and work performance indirectly in order to develop an eco driving system. Firstly, we developed equations which could predict tractor power output and fuel consumption rate using characteristic curves of tractor power output. Secondly, with actual engine rpm determined by initial engine rpm and work load, tractor power output and fuel consumption rate were forecasted. Thirdly, with speed signals of GPS sensor system, it was possible to foresee tractor work performance and fuel consumption rate. Lastly, precision of the eco driving system was evaluated through tractor PTO test, and effects of the eco driving system were investigated in the plowing and rotary tilling operations. Engine rpm, power output, fuel consumption rate, work performance and fuel consumption rate per plot area were displayed in the eco driving system. Predicted tractor power outputs in the full load curve were well coincided with the actual power output of prototype, but small differences, 1 to 6 ㎾, were found in the part load curve. Error of the fuel consumption rate was 0.5 L/h, 4.5%, the greatest, and 1 to 3 L/h at the part load curve. It was shown that 69% and 53% of fuel consumption rates could be reduced in plowing and rotary tilling operations, respectively, when the eco driving system was installed in tractor.

• 한국가스학회지
• /
• 제13권5호
• /
• pp.1-6
• /
• 2009

본 논문에서는 LPG 차량의 연비효과에 미치는 대기온도, 증발기의 가스누출, 엔진오일의 점도, 엔진의 부하조건을 실험적으로 고찰하고자 한다. 연비에 대한 시험결과에 의하면, 엔진의 온도가 상승할수록 연비효과도 함께 점차 높아지고 있다. 대기온도가 $24.2^{\circ}C$일 때의 연비는 $1^{\circ}C$일 때보다 13.6% 정도 높게 나타난 것을 알 수 있다. LP가스 누출이 없는 증발기의 연비는 가스누출이 있는 경우에 비해 5.3%나 좋아지는 것으로 확인되었다. 반면에 엔진오일을 새로 교환한 경우의 연비는 9,500km를 주행한 오일에 비해 1.1% 정도 향상된 것으로 나타났으며, 이것은 대기온도나 증발기의 누설조건에 비해 상대적으로 낮은 영향을 미치는 것으로 관찰되었다. 연비에 더 많은 영향을 미치는 요소는 급제동, 급출발, 급가속과 같은 운전조건으로 판단된다. 연비시험 결과에 의하면, 정상출발은 급출발에 비해 32.3%나 연비가 향상되었고, 급가속은 급출발보다 10.8%나 우수한 연비조건을 보여주고 있다. 또한, 급제동은 급출발보다 18.3%나 우수한 연비상태를 나타내고 있다. 결국 비정상적인 주행조건은 정상적인 운전패턴에 비해 연비가 나쁜 것으로 나타났으므로, 연비를 높이기 위해서는 차량의 주행조건을 정상상태로 유지하는 것이 대단히 중요함을 알 수 있다.

• 한국기계기술학회지
• /
• 제13권3호
• /
• pp.17-23
• /
• 2011

To estimate fuel consumption of a vehicle, a car can be tested on chassis dynamometer. In this case, test causes a lot of time and money. To predict the fuel efficiency of vehicles in the design stage or early stage of development, the development of computer simulation model is necessary. Using simulation to predict the fuel consumption, the driving model which consists of time-velocity profile and time-grade profile is necessary In this study, vehicle model is developed in MatLab/simulink to estimate real driving fuel consumption rate with time-velocity profile, time-shift gear profile and time-grade profile. Vehicle model consists of driver model, engine model, power train model, and so on. On-road vehicle tests to verify the vehicle model are carried out for analyzing the result of simulation and comparing with those of the experiments.

• 오토저널
• /
• 제15권3호
• /
• pp.47-54
• /
• 1993

This paper describes briefly the effect of ultrasonic fuel supply device on the performance of four stroke cycle gasoline engine. Experiments were carried out to clarify the effect of ultrasonic fuel supply device on the engine output, traveling fuel consumption ratio, exhaust emissions. The results were obtained as follows: 1.Engine output was increased 9-14% in comparison with that of the conventional injector. 2.Travelling fuel consumption ratio was improved 17-29% in comparison with that of the conventional injector. 3. CO, HC exhaust emissions was decreased compared to the value of the conventional injector. 4.Fuel consumption ratio in highway driving test was improved about 10% in comparison with that of the conventional injector.

• 한국생산제조학회지
• /
• 제24권5호
• /
• pp.541-547
• /
• 2015

In this study, the performance of a low-floor midsize bus under development is predicted through simulations. To predict the vehicle's acceleration, maximum speed, and uphill driving performance, a forward simulator which calculates the vehicle power is developed. Also we verify the forward simulator by comparing simulations and test result for benchmarking vehicle. To predict the fuel consumption, we use a backward simulator for a specified road cycle. However, to predict the fuel consumption using the backward simulation the engine fuel-consumption map is needed. The engine fuel-consumption map extracting data from a similar sized diesel engine is used by re-scaling the maximum torque. As a result, we simulate the vehicle's forward performance with a new engine. Further, we simulated the backward performance to optimize the fuel efficiency and gearshift timing.

• 융복합기술연구소 논문집
• /
• 제3권1호
• /
• pp.25-29
• /
• 2013

The purpose of this paper is to determine the fuel change and weight change impact on the fuel economy and emission characteristic of ICE (Internal Combustion Engine) vehicle. According to fuel type, fuel consumption and emission characteristics were measured and fuel used in this paper was gasoline, diesel, and LPG. Four vehicles with different weight were tested and the fuel economy were compared and analyzed by using scatter graph. Test was carried out using chassis dynamometer, CVS (Constant Volume Sampler), and emission measurement system. Diesel vehicle less emited $CO_2$ compared to gasoline and LPG. Even if same $CO_2$ between gasoline and LPG, there are difference fuel economy depending on carbon proportion of specific fuel. The heavier weight of vehicle, the worse of fuel economy and Better fuel economy performance on highway driving mode.

• Journal of Mechanical Science and Technology
• /
• 제15권10호
• /
• pp.1442-1450
• /
• 2001

The EGR system has been widely used to reduce nitrogen oxides (NO$\_$x/) emission, to improve fuel economy and suppress knock by using the characteristics of charge dilution. However, as the EGR rate at a given engine operating condition increases, the combustion instability increases. The combustion instability increases cyclic variations resulting in the deterioration of engine performance and emissions. Therefore, the optimum EGR rate should be carefully determined in order to obtain the better engine performance and emissions. An experimental study has been performed to investigate the effects of EGR on combustion stability, engine performance,70x and the other exhaust emissions from 1.5 liter gasoline engine. Operating conditions are selected from the test result of the high speed and high acceleration region of SFTP mode which generates more NO$\_$x/ and needs higher engine speed compared to FTP-75 (Federal Test Procedure) mode. Engine power, fuel consumption and exhaust emissions are measured with various EGR rate. Combustion stability is analyzed by examining the variation of indicated mean effective pressure (COV$\_$imep/) and the timings of maximum pressure (P$\_$max/) location using pressure sensor. Engine performance is analyzed by investigating engine power and maximum cylinder pressure and brake specific fuel consumption (BSFC)