• International Journal of Automotive Technology
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• v.8 no.3
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• pp.289-298
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• 2007

A nonlinear dynamic simulation model from cranking to idle speed is developed to optimize the cold start process of a diesel engine. Physically-based first order nonlinear differential equations and some algebraic equations describing engine dynamics and starter motor dynamics are used to model the performance of cold starting process which is very complex and involves many components including the cold start aiding method. These equations are solved using numerical schemes to describe the starting process of a diesel engine and to study the effects of cold starting parameters. The validity of this model is examined by a cold start test at $-20^{\circ}C$. Using the developed model the effects of the important starting variables on the cold starting processes were investigated. This model can be served as a tool for designing computer aided control systems that improve cold start performance.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.1
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• pp.53-60
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• 1994

Austenite formation and Low temperatures mechanical properties of HSLA steel of different starting structures have been studied by intercritical annealing(IA). The different starting structures are: ferrite+pearlite(FP1), martensite(M1), cold worked ferrite+pearlite(FP2) and cold worked martensite(M2). In most cases tensile strength and elongation was increased by decreasing the testing temperatures regardless of the IA time. Tensile strength of the cold worked starting structures was higher than that of the non-cold worked starting structures. However not any noticeable difference in elongation was found between two cases. Low temperatures impact properties were affected by the starting structures. Charpy V-notch impact transition temperatures of the M-starting structures were around $-40^{\circ}C$, and those of the FP starting structures were around $-10^{\circ}C$. Impact energy was lower in the cold worked specimens than in the non-cold worked specimens at the same starting structures. DP structure obtained from the M-starting structure has shown superior low temperatures mechanical properties than the DP structure obtained from the FP-starting structure.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.1
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• pp.32-39
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• 2000

To optimize the cold start process of a 4-stroke, 8 cylinder Diesel engine, a dynamic simulation model from cranking to idle speed is developed. Physically-based first order starter motor dynamics are used to model the performance of starting process which is very complex. These equations are solved using numerical schemes(Petzold-Gear BDF method) to describe the starting process of diesel engine and to study the effects of starting parameters. The validity of this model is examined by start test. This model can be served as a tool for computer aided control systems design to improve cold improve cold start performance.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.1
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• pp.18-25
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• 2022

The cold staring issue of permanent magnet synchronous motors (PMSM) is a chronic problem in the field of PMSM sensorless drives. A traditional starting method, called the I-F method, is widely adopted because of its simple structure. However, when using this method, the pre-defined magnitude and frequency of the starting current should be changed according to the condition of the load and machine inertia. In this paper, a smart and simple algorithm for the cold starting of PMSM is proposed. In the proposed method, an integrated control angle from the estimated electrical rotor speed is used for vector control such as the indirect vector control of the induction machine. Thus, very stable cold starting is performed regardless of the machine load condition or inertia changing.

• 전기의세계
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• v.13 no.4
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• pp.10-15
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• 1964

It is well known that the starting characteristics of the cold cathode type discharge tube have photoelectric effects by the incident light from outside. After making the cold cathode type discharge tubes to be avaiable for popularizing, the present paper was devoted primaliry to a study of relations between the starting characterstics and photoelectric effects of discharge tube under the oight circumstances of day light, incandescent lamp, flouresent lamp, and mercury lamp we used frequently. The result of this investigation show that the photoelectric effects by flourescent lamp emitting short wave length having close ralation to the photoelectric effects is greater than incandescent lamp or day light, and also mercury lamp emitting shorter wave length than flourescent lamp indicates the greatest photoelectric effects.

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.11-18
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• 2003

This study was carried cut to get basic data of troubles in starting and supply of farm diesel engines in cold winter. The results of the study are summarized as follows: 1. As the result of farm survey. the proportions of farms which had starting problems or troubles in fuel supply in cold winter for the last 5 years were 38% for the farms with power-tillers and 32% for the farms with tractors. Most of the farms which had starting problems or troubles in fuel supply in cold winter used light oil for summer. spring or fall rather than for winter. 2. As the result of fuel supply test, fuel supply was stopped at -6$^{\circ}C$ and -18$^{\circ}C$ for summer light oil and winter light oil. respectively 3. The lowest temperatures of winter light oil for starting engine were -7.5$^{\circ}C$ for power-tiller. -12.5$^{\circ}C$ for tractor of 38ps, and -17.5$^{\circ}C$ for tractor of 45ps. which were 5~7.5$^{\circ}C$ lower than that of summer light oil. 4. The performance of engine starting and the trouble of fuel supply system at lower temperature were significantly improved by using winter hight oil rather than summer light oil.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2910-2915
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• 2008

This paper was investigated the behaviors of the engine and combustion phenomena for various LPG compositions in the semi-return type system, which is not recircurated to LPG tank through furl rail, applied LPi engine during a cold idle condition and including a cold start of the engine. Cyclic HC and NOx emissions were measured at exhaust port to examine their formation mechanical and reduction mechanical with fast response gas analyzers. Various ignition timing is experimented to study the characteristics of combustion phenomena, HC/NOx emissions during fast idle. Also, this study was investigated start delay time, cylinder pressure, HC/NOx emissions, Mass Fraction Burned, starting time to evaluate performance of transient cold startability. Compared to the return type system, the semi-return type system have advantages in point of production cost and equivalent performance of engine starting time and pressure settling time.

• 전기의세계
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• v.14 no.3
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• pp.18-27
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• 1965

It is well known that the starting characteristics of the cold cathode type discharge tubes are irregular. We have two kinds of stabilization for starting characteristics of discharge tubes. Which are the aging test immediately after producing the tubes and the using characteristics. This paper was devoted primaliry to the empric study of relation between the aging and the manufacturing process. And then to stabilize the starting characteristics of discharge tubes by the irradiations of radio-isotope.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.2
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• pp.1-10
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• 2001

In order to reduce hydrocarbon emissions of spark ignition engine, it is important not only to improve catalyst conversion efficiency but also to reduce direct engine out hydrocarbon emissions, during cold starting and warm up process. Tjerefore many researchers have been attracted to develop an early fuel evaporator (EFE) by introducing a ceramic heater for a solution of engine out hydrocarbon emissions in SI engine. But, the performance of the EFE in MPI engine to reduce the exhaust emissions and to improve the cold startability has nat been clarified yet. The purpose of this study is to evaluate the feasibility of a glow plug for EFE.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.1
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• pp.84-92
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• 2002

On the cold start of LPG engine, as the engine temperature has not reached its equilibrium temperature, liquid LPG could not be changed perfectly gaseous LPG, although it was passed to the vaporizer. Liquid and gas mixed fuel could influence starting ability and exhaust emission characteristics of LPG engine. In this study, the vaporization characteristic of liquid LPG was investigated with a conventional vaporizer and the vaporizer with heat source(glow plug) installed at preheated chamber inlet, by using the visualization methods and engine test. According to visualization result, even if the engine coolant temperature was $14^{\circ}C$, liquid fuel was supplied to primary chamber over 25 seconds without vaporizing from preheated chamber in such a conventional vaporizer. However, the vaporizer with heat source do not correspond with that, scarcely had been trim on glow plug when LPG began to vaporize. The effectiveness of heat source could be verified by application to the conventional LPG engine.