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Viewing 31 to 60 of 10280
2016-04-05
Technical Paper
2016-01-0655
Farid Bahiraei, Amir Fartaj, Gholm-Abbas Nazri
Li-ion batteries are leading candidates for hybrid and electric vehicles as environmentally friendly means of transport. The main barriers for widely deployment of these batteries in electric vehicles are safety, cost, and poor low temperature performance, which are all challenges related to battery thermal management system (BTMS). Therefore, an effective thermal management strategy is crucial for enhancing the system lifetime and increasing vehicle range. In this study, a coupled thermal-electrochemical model for prismatic cells is primarily developed to simulate the battery cell chemistry and heat generation. This model is also used to investigate the effectiveness of active and passive cooling systems. The active cooling system under study utilizes cooling plates and water-glycol mixture as the working fluid while the passive cooling system incorporates a phase change material (PCM).
2016-04-05
Technical Paper
2016-01-1436
K. Han Kim, Sheila Ebert-Hamilton, Matthew Reed
Automotive seats are commonly described by one-dimensional measurements, including those documented in SAE J2732. However, 1-D measurements provide minimal information on seat shape. A 3-D scanner may provide high-resolution details, but due to inconsistent vertex and polygon compositions, indexing and comparing geometries across different seats are extremely difficult. The goal of this work was to develop a statistical framework to analyze and model the surface shapes of seats by using similar techniques that have been used for modeling human body shapes. The 3-D contour of twelve driver seats of sedans and pickup trucks were scanned and aligned, and 332 landmarks were identified using a semi-automatic process. A template mesh of 18,306 vertices was morphed to match the scan at the landmark positions, and the remaining nodes were automatically adjusted to match the scanned surface. A principal component (PC) analysis was performed on the resulting homologous meshes.
2016-04-05
Technical Paper
2016-01-0206
Ken T. Lan
An Air intake system (AIS) is a duct system which leads the airflow going into the internal combustion engine. Combustion requires oxygen and the more oxygen you give into the combustion process the more power you will get from it. The lower the air temperature, the higher its density, and hence more oxygen in a unit volume. The quality of air entering engine can be measured with the air temperature. AIS routing influences the air charge temperature (ACT) at intake manifold runners, and ACT normally is measured at AIS throttle body in reality. Higher ACT lead to inefficient combustion and can lead to spark retard. Optimization of AIS routing and reduction of ACT can improve engine performance and vehicle fuel economy. High ACT can be a result of two different phenomena: • Recirculation – Hot air from the under hood environment ingested into the dirty side of the air inlet system.
2016-04-05
Technical Paper
2016-01-1295
Atsushi Itoh, ZongGuang wang, Toshikazu Nosaka, Keita Wada
Electric vehicle has quiet in the cabin, but on the other hand, it becomes easy to perceive refrigerant-induced noise in automotive air-conditioning system. In the case of purchasing air-conditioning components from some suppliers separately, it is crucial to verify whether refrigerant-induced noise occurs in system or not before air-conditioning components are assembled. If target noise occurs less frequently, it is difficult to evaluate in a vehicle testing. This paper presents 1D modeling methodology for simulation of refrigerant-induced noise such as self-excitation noise generated by pressure pulsation through thermal expansion valve. A GT-SUITE commercial code was used to develop a refrigerant cycle model, consisting of compressor, condenser, evaporator, thermal expansion valve and connecting pipe network.
2016-04-05
Technical Paper
2016-01-0080
Hiroyuki Miyake
This paper explains a performance enhancement of the lane guidance function in car navigation systems.In order to achieve intuitive lane guidance, a function is considered that displays lane guidance on an image of the front scene that matches what drivers actually see outside the vehicle.Therefore, two developed items were lane accurate positioning based on image recognition and augmented reality visualization that renders lane guidance images overlaid on the scenery of the road ahead.The eye glance time to the navigation screen has been reduced in a comparison test with a conventional lane guidance method. It is confirmed that this lane guidance function is more intuitive than the conventional method.
2016-04-05
Technical Paper
2016-01-0240
Ruobing Zhan, Gangfeng Tan, Bo Yang, Zhiwei Zhang, Tie Wang, Cenyi Liu, Xintong Wu, Yanjun Ren, Haobo Xu
The Organic Rankine Cycle System(ORC) is an effective means to use solar energy. The system adopts the solar energy on the car roof as the heat source to make Organic Rankine Cycle work and drive thermoelectric air-conditioner.It can improve the entering comfort on the parking condition and the vehicle energy utilization efficiency .In this research, the system conprehensively applied the principle of sunshine concentration, heat collection and photoelectricity. Then considering the working condition and performance features of ORC system,the car roof was designed to have a compact structure, through which the efficiency of solar vehicle system could be improved. Firstly, the research analyzed the heat source temperature and the heat flux impact on the output power of the ORC system. After that, the performance of heat collection was identified according to the given thermoelectric air-condition’s power requirements.
2016-04-05
Technical Paper
2016-01-0222
Xingyu Zhang, Bo Yang, Gangfeng Tan, Binyu Mei, Zhilei Li, Zhongjie Yang, Can Wang
Abstract: Heavy duty trucks cover heavy engine load and often drive long distances in complicated geographical conditions. In the traditional fixed transmission ratio fan cooling system, the capacity of cooling system is insufficient and the engine is easy to be over-heated when the engine is working in low speed and heavy load conditions. Owning to the bulk mass of electric fan, it is unsuitable for heavy duty trucks. Hydraulic-driven cooling system with some advantages of small size, large power, convenient speed adjustment and flexible installation location is widely applied in heavy duty trucks. But the low transmission efficiency results in high power consumption of the fan. Furthermore, the delaying response of the hydraulic-driven system restricts the precise temperature control of the cooling system. The study applies the neural network to control the hydraulic-driven cooling system and considers the delaying characteristics of hydraulic system.
2016-04-05
Technical Paper
2016-01-0228
Mengzuo Han, Gangfeng Tan, Xuexun Guo, Ruobing Zhan, Xuyang An, Weiye Xue, HongBo Kang
Vehicle exhaust waste-heat recovery with thermoelectric power generators can improve energy efficiency, as well as vehicle fuel economy. In the conventional structure, the hot-end of thermoelectric module is directly connected with the outer wall of the exhaust pipe, while the cold-end is connected with the water pipe’s outer wall of the vehicle engine cooling cycle. However, the variety of vehicle engine operating conditions leads to instability of the hot-end temperature, which will reduce the generating efficiency of the thermoelectric modules and also shorten its service life. This research is on the basis of constructing a heat transfer oil circulation, and to study the action principles and implementation methods of it.
2016-04-05
Technical Paper
2016-01-0239
Li Zhou, Gangfeng Tan, Xuexun Guo, Ming Chen, Kangping Ji, Zhilei Li, Zhongjie Yang
The hydraulic retarder is an auxiliary braking device used in heavy duty truck. The traditional thermal management system of hydraulic retarder dissipates transmission fluid heat out of the truck directly, it’s a big waste of energy while thermal management system components need to consume engine power. This study applies organic Rankine cycle(ORC) cooling system to meet the high power hydraulic retarder cooling requirements and recovering waste heat energy from hydraulic retarder transmission fluid to supply energy demand of thermal management system, which save the parasitic power of the engine and improve the vehicle comprehensive energy utilization. Firstly, the retarder heat model and ORC thermodynamic model is established based on a certain type of hydraulic retarder. The power output characteristics of ORC and the control method of circulation flow rate is studied under the premise that the retarder import and export oil temperature meet requirements.
2016-04-05
Technical Paper
2016-01-1411
Sangmin lee, Donghwa Shin, Jongseok Park, Ng Eng Chong, Fabrizio Cortigiani, Youngjae Choi
LED in automotive rear combination lighting (RCL) is becoming widely used in high end to mid class segment car. This is mainly fuelled by the strong influence of styling and requirement of a compact design. With OEMs competing to provide higher value to the customers such as longer warranty and advanced diagnostic features, the topic of semiconductor integration is becoming significant. Integration is a key to enable small form factor, high robustness and implementation of advanced technical functionality in the LED driver. However, the cost of implementing an integrated driver, if not partitioned effectively, will be much higher than the discrete solution. Therefore, it is important to implement the cost optimization strategy right from the conceptualization of the LED driver integrated device. In the beginning of this paper, the LED driving concept that is commonly used in the RCL lighting such as linear current sources and switching supply discussed.
2016-04-05
Technical Paper
2016-01-0525
Sameer Srivastava, Sandeep Raina, Kapil Kumar Pandey, Arnab Sandilya, Shankar Bose, Kumar Vivek
An automobile Carpet comprises a face fabric (Poly Ehtylene Terephthalate a.k.a PET) for aesthetics with Poly Ethylene lamination/backing (for strength such as Tear, Abrasion etc and Sound barriers to some extent) and Silencer pads functioning as Sound Absorbers and cushioning effect. In a strive to maintain quality, myriads of checks/tests are done during the part development stages. However, in due course of time its exposure to Sunlight and severe weather conditions degenerate the aesthetic quality. Carpets prepared with appropriate additives, UV stabilizers, apposite lamination/backing have shown protracted and extended performance. This paper relates to effects of ageing on aesthetic performance of Automotive Non-Woven Fabrics.
2016-04-05
Technical Paper
2016-01-1410
Stefan G. Grötsch, Morten Brink, Roland Fiederling, Thomas Liebetrau, Ingo Möllers, Jörg Moisel, Hermann Oppermann, Alexander Pfeuffer
The technology for ADB/AFS systems is facing a transition to addressable LED arrays. ADB concepts today on the market use single row and multi row solutions. The “µAFS” consortium funded by the German Ministry of Research and Education consisting of Daimler, Hella, OSRAM SP and OS, Fraunhofer IZM and IAF and Infineon wants to go one step further. By hetero integration of a LED Chip providing 256 pixels with an intelligent driver IC, a building block for high resolution ADB/AFS light sources with more than 1000 pixels is realized. New headlamp design and optic solutions can be adapted to this illumination source with a pixel size in the range of 0.1 mm. In parallel the electronic infrastructure on the lamp and vehicle side is redefined to deal with the communication requirements coming along with high pixel numbers. New processing concepts create adaptive high resolution light patterns in real time and allow the car integration.
2016-04-05
Technical Paper
2016-01-0221
Roberto Monforte, Fabrizio Mattiello, Andrea Perosino, Fabrizio Porta, Susanna Paz, Pablo Lopez del Rincón
The adoption of a low-GWP refrigerant gas in MAC systems is mandatory from 2017 according to the European Directive 2006/40/EC requirements for new vehicles registration. The paper will present the activities held by CRF to support the FCA evaluation of the risk involved by the adoption of the low-GWP refrigerant gas R-1234yf in the MAC systems equipping both new types and current programs, which MACs have to be converted in order to exploit the low-GWP refrigerant gas R-1234yf in order to comply with the 2006/40/EC Directive requirements and gain vehicle registrations from January 1st, 2017. In certain concentrations, R-1234yf could present a safety hazard to the vehicle occupants or to a technician required to service the vehicle. Hazard: event which has the potential to cause harm to an individual. Risk: numerical estimate of the probability or likelihood that a given hazard will occur. Risks are estimated via the process of risk assessment.
2016-04-05
Technical Paper
2016-01-1313
Brian Pinkelman, Woo-Keun Song
Most methods of vibration analysis focus on measuring the level of vibration. Some methods like ISO-2631 weigh vibration level based on human sensitivity of location, direction, and frequency. Sound can be similarly measured by sound pressure level in dB. It may also be weighted to human frequency sensitivity such as dBA but sound and noise analysis has expanded to measure sound quality. The characteristic and the nature of the sound are studied. As an example equal or near equal sound levels can provide different experiences to the listener. Such was the question for vibration, “can vibration quality be assessed just as sound quality is assessed?” Early on in our studies vibration sensory experts found a difference in 4 seats yet we could find no objective measurement of vibration level that could reliable confirm the sensory experience. Yet these particular experiences correlated to certain verbal descriptors including smoothness or roughness.
2016-04-05
Technical Paper
2016-01-0185
Yangjie Ji, Jiaqi Wang, Yingxiao Xu, Ziang Liu, Yongchi Zhou, Jiawei Li
As an auxiliary braking device of heavy-duty vehicle, eddy current retarder can reduce the brake failure due to the high temperature of the main brake. Nevertheless, it will generate high temperature locally during the working process of the eddy current retarder, thus reducing the electrical conductivity of materials, leading to the decline of the brake power. The study on the heating characteristics of eddy current retarder is advantageous to the layout and parameter design of the liquid cooling channel of the retarder body and prolong the effective time of the auxiliary brake. In this research, a new kind of integrated eddy current retarder is established. The thermal-magnetic coupling characteristics are studied and the change laws in torque output of auxiliary brake affected by the body temperature of retarder are analyzed. The boundary conditions are provided for the construction of the cooling channel and the theoretical basis is offered to the design of liquid cooling unit.
2016-04-05
Technical Paper
2016-01-1512
Jeya Padmanaban, Roger Burnett, Andrew Levitt
This paper updates the findings of prior research addressing the relationship between seatback strength and likelihood of serious injury/fatality to belted drivers and belted rear seat occupants in rear-impact crashes. Statistical analyses were performed using 1995-2014 CY police-reported crash data from fifteen states. Seatback strength for over 100 vehicle models (model years 1996-2013) was included in the analysis. Seatback strength is measured in terms of the maximum moment that results in 10 inches of seat displacement. These measurements range from 5,989 in-lbs to 39,918 in-lbs, resulting in a wide range of seatback strengths. Additional analysis was done to see whether Seat Integrated Restraint Systems (SIRS) perform better than conventional belts in reducing driver and rear seat occupant injury in rear impacts. Field data shows the injury rate for belted drivers and belted rear seat occupants in rear-impact crashes is less than 1%.
2016-04-05
Technical Paper
2016-01-1417
Toshinao Fukui, Kazuhiko Nakamoto, Hiroyuki Satake
Recently, head up displays (HUD) have become a common visual feedback device of advanced technologies as the HUD can display feedback to the driver in a highly visible area. However, a reflection to front windshield is often caused by the outline (mikiri line) of the HUD unit on the dash board when the dash board is in direct sun light. The reflection can lead to driver annoyance on an asphalt road as well as dark view in front of windshield. In certain conditions of the front view, location and thickness, and contrast of the outlines were considered as factors impacting annoyance. These factors were considered to contribute to the visibility of stripe pattern (a contrast sensitivity function). In addition, since the reflection of the outlines can be enhanced by bright sunlight coming to the dash board, the present study considered high illuminance on the dash board as an environmental factor. This additional factor was not considered in the past study.
2016-04-05
Technical Paper
2016-01-0244
Tim J. LaClair, Zhiming Gao, Omar Abdelaziz, Mingyu Wang, Edward Wolfe, Timothy Craig
Cabin heating of current electric vehicle (EV) designs is typically provided by the traction battery, since waste heat is not available from an engine as in the case of a conventional automobile. In very cold climatic conditions, the power required for space heating of an EV can be of a similar magnitude to that required for propulsion of the vehicle. As a result, its driving range can be reduced very significantly during the winter season, which limits consumer acceptance of EVs and results in increased battery costs to achieve a minimum range while ensuring comfort to the EV driver. To minimize the range penalty associated with EV cabin heating, a novel climate control system that includes thermal energy storage from an advanced phase change material (PCM) has been designed for use in EVs and plug-in hybrid electric vehicles (PHEVs).
2016-04-05
Technical Paper
2016-01-1355
Jeffrey R. Hodgkins, Walter Brophy, Thomas Gaydosh, Norimasa Kobayashi, Hiroo Yamaoka
Current CAE (computer aided engineering) methods used to develop vehicle interior noise performances have always had the reputation for being inaccurate in predicting acoustic behavior in the mid-frequency range (300 to 1000 Hz). It is in this frequency range where the overall acoustic performance becomes sensitive to not only the contributions of structure-borne noise components, which CAE has proven capable of predicting, but also the growing contributions of air-borne noise components, where CAE usually lacks the capability to accurately reflect the physics involved in complex vibro-acoustic systems. This paper will discuss a study that was undertaken to test the capability of a finite element modeling method that can accurately simulate air-borne noise phenomena in the mid-frequency range. This modeling method was used to create a model of an enclosed simple box-shaped vibro-acoustic system fit with various acoustic trim parts (carpet and under body covers).
2016-04-05
Technical Paper
2016-01-0225
Peixiang Tang, Yunqing Zhang, Zhibao Xu, Qiming Tao
Vehicle Thermal Management System (VTMS) is a crosscutting technology affecting the fuel consumption, engine performance and emissions. With the new fuel economy targets approved and the requirement of vehicle performance enhanced, being able to predict the impact on the fuel consumption of any modification made on the VTMS is becoming an important issue in the pre-prototype phase of vehicle development. This paper presents a methodology using different simulation tools to model the entire VTMS in order to understand and quantify its behavior. The detailed model contains: engine cooling system, lubrication system, powertrain system, intake and exhaust system, HVAC system. In this modle, a link is used to pass the power absorbed by the operating of the components in VTMS such as pumps and condenser to the engine. This absorbed power is taken into account in the computation of the power developed by the engine shaft.
2016-04-05
Technical Paper
2016-01-0217
Somnath Sen, Mayur Selokar, Diwakar Nisad, Kamal Kishore
Adequate visibility through the vehicle windshield over the entire driving period is of paramount practical significance. Water film (fog) that forms on the windshield mainly during winter times would reduce and disturb the driver’s visibility. This water film originates from condensing water vapor on the inside surface of the windshield due to low outside temperatures. Primary source of this vapor is the passenger’s breath, which condenses on the windshield. Hot and dry air which impinges at certain velocity and angle relative to the windshield helps to remove the water film (defogging) and hence improves driver’s visibility. So, a well-designed demisting device will help to eliminate this fog layer within very short span of time and brings an accepted level for visibility. An attempt is made here to design and develop a demisting device for a commercial vehicle with the help of numerical and analytical approach and later on validated with experimental results.
2016-04-05
Technical Paper
2016-01-0652
Ravi ranjan, Lakshmaiah Brahmasani, Parvej khan
This paper reports a study on Charge air cooler effectiveness, Pressure drop and Acceleration Performance of a utility vehicle, for different layouts positioning of Inter cooler, radiator, condenser and fan module in order to finalize efficient Power train cooling system layout. The main objective was effective utilization of front end opening area, eliminating inter cooler heat load on the radiator, so that radiator size, fan size and Fan Motor wattage can be optimized to achieve desired cooling performance requirements with the cooling system (CRFM) module. Effect of the inter cooler effectiveness, Intake pressure drop and Vehicle acceleration were studied to finalize the position of inter-cooler along with other engine cooling components. The cooling system restriction was optimized (reduced) by reducing radiator core thickness with finalizing inter cooler position just above the radiator.
2016-04-05
Technical Paper
2016-01-0181
Yasuki Hirota, Ryuichi Iwata, Takafumi Yamauchi, Manabu Orihashi, Masaki Morita
In order to reduce the energy consumption of the automotive air conditioning system, adsorption heat pump (AHP) system is one of the key technologies. We have been developing compact AHPs system utilizing the exhaust heat from the engine coolant system (80-100 degree C), which can meet the requirements in the automotive application. However, AHPs system have not been practically used in automotive applications because of its low volumetric power density of the adsorber. The volumetric power density of the adsorber is proportional to sorption rate, packing density and latent heat. In general, the sorption rate is determined by mass transfer resistance in primary particle of an adsorbent and heat and mass transfer resistance in packed bed. In order to improve the volumetric power density of the adsorber, it is necessary to increase the production of the sorption rate and the packing density.
2016-04-05
Technical Paper
2016-01-0646
Pablo Olmeda, Jaime Martin, Antonio Garcia, Diego Blanco, Alok Warey, Vicent Domenech
Regulated emissions and fuel consumption are the main constraints affecting engine design. Over the years, many techniques have been used with the aim of meeting these limitations. In particular, EGR has demonstrated to be a necessary solution to reduce NOx emissions, becoming a widely used technique in production diesel engines. However, its application has a direct effect on fuel consumption due to both the changes in the in-cylinder processes, affecting indicated efficiency, as well as air management. An analysis, based on the engine Global Energy Balance, is presented to thoroughly assess the behavior of a HSDI diesel engine under variable EGR conditions at different operating points. The tests have been carried out, while keeping combustion phasing and conditions at intake valve closing (IVC) fixed.
2016-04-05
Technical Paper
2016-01-0100
Sushant Kishor Hingane
The high-end vehicles with latest technology and autonomous driving experience have to bear the cost of increasing number of sensors on-board. It would prove to be the most beneficial to reduce some of the sensors in vehicle and make use of other available resources, retaining the same functionality. This paper discusses a technique of estimating the weight of seat occupant from an already existing DC motor; without using additional pressure sensors. Passenger weight information is important for seat-belt reminder system as well as supplementary restrain system that will decide the air-bag deployment. A mathematical model for a series-type DC motor is developed and simulated using MATLAB. Further, results are shared of the lab experiment performed on a lower capacity motor and verified with the simulation results. Along with the comparison of the simulated data and sensor set-up results, a concluding linear relation is formulated.
2016-04-05
Technical Paper
2016-01-0254
Gursaran D. Mathur
In southern states (e.g., Arizona) typically people drive their vehicles in summer by running vehicle’s air conditioning systems in recirculation modes only. Carbon dioxide exhaled by occupants remains within the cabin during operation in recirculation mode. The concentration of carbon dioxide starts increasing in the cabin. The CO2 that is inhaled by the occupants goes into their blood stream that negatively affects occupant’s health. ASHRAE Standard 62 specifies the safe levels of carbon dioxide in conditioned space for humans. The CO2 concentration limit per ASHRAE is 700 ppm over the ambient conditions on a continuous basis. Current global average ambient concentration level of CO2 as of March 2015 is approximately 401 ppm. Hence, if the CO2 concentration exceeds approximately 1100 ppm inside of a home or a vehicle cabin, then we must introduce outside air into the home or vehicle cabin to reduce the CO2 concentration.
2016-04-05
Technical Paper
2016-01-0241
Sina Shojaei, Simon Robinson, Andrew McGordon, James Marco
The power demand of air conditioning system in PHEVs is known to have a significant impact on fuel economy and performance. Besides the cooling power associated to the passenger cabin, in many PHEVs, the air conditioning system provides cooling power to the high voltage battery’s cooling system. Calculating the exact cooling power demands of the cabin and battery and their impact on the vehicle performance can lead to developing optimum system design and energy management strategies. In this paper, a representative vehicle model is used to calculate the cooling requirements over a number of 24-hour duty cycles. A number of pre-cooling and after-run cooling strategies are studied and effect of each strategy on the performance of the vehicle including, energy efficiency, passenger thermal comfort and degradation of the battery are calculated.
2016-04-05
Technical Paper
2016-01-0657
Sethuramalingam T, Chandrakant Parmar, Sashikant Tiwari
In conventional Passenger cars with rear engine, radiator is located at the rear end of the car. The thermal management of cooling system becomes challenging due to inadequate air flow through the radiator. This paper is about designing a distinctive cooling system where the radiator is mounted in the front of the car. However this kind of arrangement requires lengthy coolant lines extended between the radiator and the engine, routed beneath the vehicle. The U-shaped arrangement where radiator and engine are at higher coolant head and cooling lines are at very low coolant head becomes very critical as air traps in the coolant system during coolant filling and de-aeration process. This restricts the coolant circulation during vehicle running-in and thus affect the life of critical components due to overheating.
2016-04-05
Technical Paper
2016-01-0283
Joydip Saha, Harry Chen, Sadek Rahman
More stringent Federal emission regulations and fuel economy requirements have driven the automotive industry toward more sophisticated vehicle thermal management systems which may include various new technologies such as active grill shutter, variable coolant flow control devices, PWM controlled fan and control strategies in order to best utilize the waste heat and minimize overall power consumption. With these new technologies and new devices, the comprehensive vehicle-thermal-system simulation tools are essential to evaluate and develop the optimal system solution for new cooling system architectures. This paper will discuss how the model-based vehicle thermal system simulation tools have been developed from analytical & empirical data, and have been used for assessment and development of new cooling system architectures.
2016-04-05
Technical Paper
2016-01-0212
Paras Kaushal, Satishchandra C. Wani
TeamIndus is Indian participant in the Google Lunar X prize (GLXP). The mission objective is to soft-land a rover on the Moon, travel for 500 meters and transmit HD images & videos back to Earth. TeamIndus is designing lunar Lander/Spacecraft which will carry the rover to lunar surface assisting during surface operations in accomplishing mission objectives. The mission consists of four phases- Earth orbits, Moon orbits, lunar descent and lunar surface operations, however this paper discusses about lunar descent and lunar surface operations. The descent phase begins at an altitude of 12.5 km from lunar surface and occurs in three phases viz. braking phase in which almost all the orbital velocities are killed, Approach phase in which the spacecraft will be oriented in the desired orientation and Terminal phase during which any residual lateral velocities are removed and engines are cut off from predetermined height above lunar surface for free fall.
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