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2016-05-05
Journal Article
2015-01-9148
Saeed Asgari, Shailendra Kaushik
Abstract A linear parameter varying (LPV) reduced order model (ROM) is used to approximate the volume-averaged temperature of battery cells in one of the modules of the battery pack with varying mass flow rate of cooling fluid using uniform heat source as inputs. The ROM runs orders of magnitude faster than the original CFD model. To reduce the time it takes to generate training data, used in building LPV ROM, a divide-and-conquer approach is introduced. This is done by dividing the battery module into a series of mid-cell and end-cell units. A mid-cell unit is composed of a cooling channel sandwiched in between two half -cells. A half-cell has half as much heat capacity as a full-cell. An end-cell unit is composed of a cooling channel sandwiched in between full-cell and a half-cell. A mass flow rate distribution look-up-table is generated from a set of steady-state simulations obtained by running the full CFD model at different inlet manifold mass flow rate samples.
2016-04-05
Technical Paper
2016-01-0647
Azmi Osman, M. Khairul Arif Muhammad Yusof, Mohammad Rafi
Additional fuel consumption reduction during the NEDC test cycle and real life driving can be effectively achieved by quickly raising the temperatures of the powertrain’s parts, oils and coolant closer to the optimal operating temperatures. In particular, the engine cooling system today must play a bigger role in the overall thermal management of the powertrain’s fluids and metals during warm-up, idle and severe operating conditions. In responding to these additional requirements, the previously proposed cost effective split cooling system has been further evolved to expedite the powertrain’s warming up process without compromising the overall heat rejection performance during severe operating conditions. In achieving these warming and cooling functions, the coolant flow rate in the cylinder head is almost stagnant when the single thermostat is closed and at its maximum when the thermostat is fully opened.
2016-04-05
Technical Paper
2016-01-0179
In this article, the behavior of a typical air-to-air heat exchanger (intercooler) during the thermal shock test has been recorded during which the heat exchanger is exposed to very high temperature gradients. Different CAE models have been built that have different level of details and the sensitivity of the results to the details has been studied. Finally a comparison have been made between the results of the CAE/CFD model and the experimental data and the correlation study shows that in spite of being simple, the dual stream is very accurate and correlates pretty well with test data. Including too many design details in the CAE model will not necessarily improve the accuracy of the model while adding up to the computational cost.
2016-04-05
Technical Paper
2016-01-1403
Jeff D. Colwell, Christopher D. Henry
Data from a full-scale vehicle burn test involving a cargo van illustrated that the fire progressed in distinct stages. After the fire was initiated on the driver’s side of the engine compartment, it slowly grew over a relatively long time period to involve nearby locations. Once the peak temperature reached about 540°C, the rate of flame spread increased such that over the next 4 minutes the fire spread across the entire engine compartment. In the next stage of the fire, which occurred shortly after full involvement of the engine compartment, the fire spread into the passenger compartment. A strong vertical temperature gradient developed from the ceiling to the floor and as the passenger compartment became fully involved, the passenger compartment temperatures both increased and became more uniform. Although oxidation and melted aluminum patterns were created during the burn test, neither correlated well with the origin of the fire.
2016-04-05
Technical Paper
2016-01-0233
Masayoshi Mori, Manabu Matsumoto, Makoto Ohtani
In order to commercialize thermoelectric heat recovery systems, appropriate cost effectiveness is required. Thus, to improve cost effectiveness, TEG (ThermoElectric Generator) structure compatible with high efficiency and low cost is considered. For achieving high efficiency, a means to utilize high exhaust temperature is investigated. The most preferable installation position is just after the close-coupled catalyzer, but due to strict space limitations, the TEG needs to be small. Therefore, a vacuum space structure is proposed to reduce the size of the TEG and enable installation. 1D system simulation is conducted and clarified that installation of the TEG just after the close-coupled catalyzer results in twice as much power generation compared to normal underfloor installation. For achieving low cost, a means to reduce the number of thermoelectric elements in TEG is examined.
2016-04-05
Technical Paper
2016-01-0236
Forrest Jehlik, Eric Rask, Michael Duoba
It is widely understood that cold ambient temperatures negatively impact vehicle system efficiency. This is due to a combination of increased friction (engine oil, transmission, and driveline viscous effects), cold start enrichment, heat transfer, and air density variations. Although the art of quantifying steady state vehicle component efficiency is well understood, transient component efficiencies over dynamic ambient real world conditions is less well understood and quantified. This work characterizes wheel assembly efficiencies of a conventional and electric vehicle over a wide range of ambient conditions. Dynamometer testing over three ambient temperatures and drive cycles was conducted with vehicles instrumented to determine the losses of the output energy of the tire on the dynamometer proportional to the input energy of the half-shafts.
2016-04-05
Technical Paper
2016-01-0203
Yadong Deng, Chunhua Liu, Panqi Chu
In order to make full use of engine exhaust heat, the thermoelectric module is used to contribute to thermoelectric power generation in the automotive. At present, the thermoelectric generators (TEGs) have been developing with continuously advances in thermoelectric technology. And almost all of the existing thermoelectric technologies are adding a gas tank to the vehicle exhaust system which increases the exhaust back pressure and occupying excessive space of the vehicle chassis. In this study, a new TEG integrated with a front silencer muffler (FMTEG) is proposed. The muffler is reshaped as the heat exchanger, which has a polygonal cross-section. The water tank and clamping mechanism have been redesigned for the new heat exchanger. The FMTEG system’s dimensions are small that can well meet the installation requirements and has a good compatibility with the vehicle exhaust system.
2016-04-05
Technical Paper
2016-01-0234
Roberto Cipollone, Davide Di Battista, Andrea Perosino, Federica Bettoja
Nowadays, in road transportation the reduction of CO2 emissions is a strategic goal and especially heavy duty vehicles, could play an important role to contribute to this objective in a significant way. The use of reciprocating internal combustion engines (ICE) dominates the sector, in particular as regards heavy commercial vehicles. However, about one third of the fuel energy used in an internal combustion engine is rejected to the environment as thermal waste through the exhaust gases. Therefore, a greater fuel economy might be achieved recovering this energy and converting it into useful electric power on board: this is very interesting in particular for long hauling vehicles, which run for miles at the same operating point. In this activity, an ORC-based power system was developed and coupled with a heavy duty diesel engine. The recovery unit, that used as working fluid R245fa, was designed in order to maximize the waste heat recovery and the electrical energy produced.
2016-04-05
Technical Paper
2016-01-0235
Serenat Karagoz, Murat Karaer, Nurettin Ali Dasdemir
Durability tests of heavy duty engines are made at R&D Test Center in Ford Otosan Inonu Factory. These tests take average 22 hours in a day without problem at engine. The total heat supplied to the engine in the form of fuel, approximately 40% is converted into useful mechanical work; the remaining heat is expelled to the environment through exhaust gases and engine cooling systems. Here, there is huge waste heat energy and it throws away to atmosphere. Project aim is recover this waste heat energy and use it at facility needs. System are designed to remove thermal energy from the exhaust gas of diesel and transfer it to water circuit. In winter, the extracted heat will be used for space heating of test cell or office. In summer, absorption chiller will use waste heat at cooling process of chiller water. With the aid of exhaust heat energy, natural gas consumption of boiler will be decreased in winter, the electric consumption of chiller will be decreased in summer.
2016-04-05
Technical Paper
2016-01-0211
Wang Yiping, Shuai Li, Chunhua Liu, Tao Wang, Panqi Chu
For vehicle thermoelectric generator, heat would been directly transferred into electricity by thermoelectric modules because there was temperature difference between heat exchanger and water tank. The electrical power generation was deeply influenced by temperature difference ,temperature uniformity and topological structure of TEG. In previous works, increasing the difference of temperature would significantly enhance the power generation of TEG and inserted fins were always applied to enhance heat transfer in parallel-plate heat exchanger. But fins would result in a large backpressure which was not conductive to efficiency of the engine. In current study, to enhance heat transfer rates and outside surface temperature, cylindrical grooves on the top and bottom surface in heat exchanger was proposed .The groove geometries were cylindrical grooves with rounded transitions to the adjacent flat surfaces.
2016-04-05
Technical Paper
2016-01-0207
Ivan Arsie, Andrea Cricchio, Cesare Pianese, Vincenzo Ricciardi, Matteo De Cesare
In the last years, the research effort of the automotive industry has been mainly focused on the reduction of CO2 and pollutants emissions. In this scenario, concepts such as the engines downsizing, stop/start systems as well as more costly full hybrid solutions and, more recently, Waste Heat Recovery technologies have been proposed. These latter include Thermo-Electric Generator (TEG), Organic Rankine Cycle (ORC) and Electric Turbo-Compound (ETC) that have been practically implemented on few heavy-duty applications but have not been proved yet as effective and affordable solutions for passenger cars. The paper deals with modeling of ORC power plant for simulation analyses aimed at evaluating the opportunities and challenges of its application for the waste heat recovery in a compact car, powered by a turbocharged SI engine.
2016-04-05
Technical Paper
2016-01-1204
Dongchang Pan, Sichuan Xu, Chunjing Lin, Guofeng Chang
As one of the most crucial components in electric vehicles, power batteries generate abundant heat during charging and discharging processes. Battery thermal management system (BTMS), which is designed to ensure the temperature of all battery cells within a safe range and maintain an even temperature distribution from cell to cell, is vital for the high efficiency, long calendar life and reliable safety of the power batteries. Conventional BTMSs such as air cooling and liquid cooling require extra power and may not meet the requirements at stressful and abuse conditions, especially at high density of heat generation and at high operating or ambient temperatures. With the desirable features of low system complexity, high energy efficiency and good battery thermal uniformity, thermal management using composite phase change materials (PCMs) has drawn specific attention in the last decade.
2016-04-05
Technical Paper
2016-01-1404
Steven E. Hodges
Fire protection, active and passive, has been, and is, an active area of concern during the design, development and deployment phases for all modern ground vehicles. All US military vehicles carry handheld fire extinguishers, and many tactical and all combat vehicles have automatic fire protection systems that protect the crew, engine, and in some cases, external components such as fuel tanks and wheels, from potentially catastrophic combat events involving fire. Vehicle designs also mitigate fire hazards by separating the vehicle occupants from the most flammable materials, e.g., fuel and ammunition, as much as practical. Explosion protection of the crew and passengers in military vehicles is a unique application with unique requirements that must balance suppr3ession effects with safety limits. This paper presents an overview of general guidelines related to protecting military ground vehicle crews from injury due to fire, and lessons learned from the experiences of fielded systems.
2016-04-05
Technical Paper
2016-01-1211
Hua Tian, WeiGuang Wang, Ge-Qun Shu, Xingyu Liang, Haiqiao Wei
Power lithium-ion battery is the core component of electric vehicles and hybrid electric vehicles (EVs and HEVs). Thermal management at different operating conditions affects the life, security and stability of lithium-ion battery pack. In this paper, a one-dimensional, multiscale, electrochemical-thermal coupled model was applied and perfected for a flat-plate-battery pack. The model is capable of predicting thermal and electrochemical behaviors of battery. To provide more guidance for the selection of thermal management, temperature evolutions and distributions in the battery pack at various ambient temperatures, discharge rates and thermal radiation coefficients were simulated based on six types of thermal management (adiabatic, natural convection, air cooling, liquid cooling, phase change material cooling, isothermal).
2016-04-05
Technical Paper
2016-01-0653
Sethuramalingam T, Chandrakant Parmar, Sashikant Tiwari
The aim of this paper is to strategize thermal protection of the engine and components in a vehicle with engine mounted in rear and radiator along with cooling fan mounted in front. An additional Exhaust Fan with speed sensor is fitted in rear mounted engine compartment and a unique monitoring technique framed in the EMS ECU is used to maintain safety of critical components like HT cables, alternators, wiring harness etc. The EMS continuously monitors the engine speed, vehicle speed and the PWM signal from exhaust fan to ensure the intended operation of the exhaust fan. With the implementation of additional exhaust fan it was observed that max engine compartment temp did not exceed safe operating temperature limit when the vehicle is driven in all road load condition (including highway, city & mountain drive tests) in all vehicle operating conditions. The component temperature was observed within acceptable operating temperature.
2016-04-05
Technical Paper
2016-01-0250
Filip Nielsen, Åsa Uddheim, Jan-Olof Dalenbäck
In recent years fuel consumption of passenger vehicles has received increasing attention by customers, the automotive industry, regulatory agencies and academia. However, some areas which affect the fuel consumption have received relatively small interest. One of these neglected areas is the total energy used for vehicle interior climate which can have a large effect on real-world fuel consumption. Realistic combinations of energy saving ideas, features and systems was evaluated regarding the total energy used for vehicle interior climate using a 1D simulation model of the important systems. The 1D simulation model included sub models of the passenger compartment, the air-handling unit, the Air Conditioning (AC) system, engine and engine cooling system. A combination of different climates were used for evaluation to better represent real-world fuel conditions.
2016-04-05
Technical Paper
2016-01-0218
Balashunmuganathan vasanth, Sathish Kumar S, Mayur SAH
In an automotive air conditioning, aero-acoustic noise originating from HVAC (Heating Ventilation and Air Conditioning) unit is one of the major concerns for the customer satisfaction. “Fan blower excessive noise” is one among the top issues for all automotive manufacturers. In this paper, a 3D computational analysis is carried out for a passenger car HVAC unit to predict the noise originated from the HVAC unit. HVAC modeling is done using Uni graphics and ANSA and the analysis is carried out using the commercial CFD software STAR CCM+. The inputs for the analysis are the airflow at HVAC Inlet, blower speed and the pressure drop characteristics of evaporator, filter and heater core. The computational model is done by considering the blower region as MRF (Moving Reference Frame) and the air flow is considered incompressible. DES (Detached Eddy Simulation) model is used to resolve the eddies generated by the turbulent flow.
2016-04-05
Technical Paper
2016-01-0249
Balashunmuganathan vasanth, Sathish Kumar S, Murali govindarajalu, Mohsin Khan
In recent years reducing the automobile HVAC (Heating Ventilation and automobile conditioning) noise inside the vehicle cabin is one of the main criterions for all OEMs to provide comfort level to the passengers. The primary function of the HVAC is to deliver more air to the cabin with less noise generation for various blower speeds. Designing the optimum HVAC with less noise is one of the major challenges for all automotive manufacturers. It is critical to predict the noise level of the HVAC during initial design stages of the program by simulation techniques since the parts shall not be available and physical testing cannot be carried out. In this study, a computational 1D (one dimensional) analysis is carried out to compute the airflow noise originated from the HVAC unit and transferred to the air coming out from the HVAC outlet for the passenger car. Modeling and meshing are done using Unigraphics and the analysis is carried out using the commercial 1D software GT suite.
2016-04-05
Technical Paper
2016-01-0255
Yinhua Zheng
This paper addresses R1234yf AC system performance impacted by condenser airflow passage blockages of non-hotspot and hotspot objects. With the modern vehicle design trend, more and more chances are existed in blocking condenser airflow passage by the objects such as TOC or fine grills etc. These objects create hotspot and narrowed airflow passages to the condenser and result in AC performance degradation. It is an important to understand: (1) which area of the condenser is less impacted by the blockages. (2) What level AC performance impact difference presents among the blockages. Thus the recommendation for packaging/designing the location of hotspots and grills can be proposed in order to mitigate these impacts on AC cooling performance.
2016-04-05
Technical Paper
2016-01-0213
Andrea Alessandro Piovano, Laura Maria Lorefice, Giuseppe Scantamburlo
The aim of this work has been to develop an advanced methodology to model the car cabin cool down test. It has been decided to focus on the fluid dynamics and thermal dynamics aspects of the phenomenon, trying to catch the correct heat transfer between the outside environment and the internal cabin with a thermal tool, together with the internal flows CFD simulation. First of all, an experimental cool down test has been conducted in the FCA Italy climatic wind tunnel on a L0 segment vehicle, to get the correlation data and the boundary conditions required for the simulation: panel ducts air transient temperatures, wind tunnel air temperature and air velocity, solar array load. The simulation has been divided in two steps: steady state soaking with a finite difference based thermal solver and transient cool down, coupling the thermal solver with a CFD one. In particular an advanced CFD/Thermal coupled approach has been applied, using STAR-CCM+ and RadTherm codes.
2016-04-05
Technical Paper
2016-01-0480
Weiguo Zhang, John White, Mark Likich, Mac Lynch
The noise radiated from the snorkel of an air induction system (AIS) can be a major noise source to the vehicle interior noise. This noise source is typically quantified as the snorkel volume velocity which is directly related to vehicle interior noise through the vehicle noise transfer function. It is important to predict the snorkel volume velocity robustly at the early design stage for the AIS development. Design For Six Sigma (DFSS) is an engineering approach that supports the new product development process. The IDDOV (Identify-Define-Develop-Optimize-Verify) method is a DFSS approach which can be used for creating innovative, low cost and trouble free products on significant short schedules. In this paper, an IDD project which is one type of DFSS project using IDDOV method is presented on developing a robust simulation process to predict the AIS snorkel volume velocity. First, the IDDOV method is overviewed and the innovative tools in each phase of IDDOV are introduced.
2016-04-05
Technical Paper
2016-01-0237
Ge-Qun Shu, Xuan Wang, Hua Tian
Because of the great resources potential and the feature of low pollution of gaseous fuel, gaseous fuel internal combustion engines (gas engines) have been paid more and more attention. However, their average thermal efficiency is just about 30-40% wasting a huge amount of energy by exhaust, cooling water and so on, so waste heat recovery is very meaningful. Both the RC (steam Ranking Cycle) and the ORC (Organic Ranking Cycle) are regarded as the suitable way of WHR (waste heat recovery) for internal combustion engines. Therein, RC is usually used in large engines. The WHR system is always designed at rated work condition, while the gas engine may often work at different conditions. This makes the property of the waste heat source change, which affects the performance of WHR system, so it is very important to research its performance at variable working condition.
2016-04-05
Technical Paper
2016-01-0229
Mohammed Ismail, Shahram Fotowat, Amir Fartaj
ABSTRACT: A numerical study is performed to investigate the transient heat transfer and flow characteristics of aluminum oxide/Ethylene glycol (Al2O3/EG) nanofluid in a multipass crossflow minichannel heat exchanger. The time dependent thermal and hydrodynamic responses of the system in a laminar regime are predicted by solving the Navier-Stokes and energy equations using the finite volume method and SIMPLE algorithm. Three-dimensional model is validated by obtaining good agreements with experimental data. The transient regime is caused by a rapid change of nanofluid mass flow rate at the inlet of the minichannel heat exchanger. In this study, three volume fractions up to 3 percent of Al2O3 nanoparticles added to the basefluid-EG are modeled and analyzed to ensure a Newtonian fluid behaviour. Al2O3/EG nanofluid is considered as a homogenous single-phase fluid. A comprehensive analysis of the transient response for the variation of nanofluids volume concentrations is conducted.
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
2016-01-0204
Igor Gritsuk, Yurii Gutarevych, Vasyl Mateichyk, Vladimir Volkov
IMPROVING THE PROCESSES OF PREHEATING AND HEATING AFTER TRANSPORT ENGINE START WITH THE HELP OF HEATING SYSTEM BY USING HEATING WITH THE HEAT ACCUMULATOR WITH PHASE TRANSITION The article discusses the features of application system of heating the vehicle engine with heat accumulator with phase transition. The peculiarity of the present system is in the fact that it uses for the heat accumulation the thermal energy of exhaust gases of internal combustion engine during its operation. The results of experimental studies of heating the vehicle engine are shown. The structure of information complex for studing the internal combustion engine of a vehicle with heating system and heat accumulator during the start and heating after starting is described. The complex allows to remote the distant evaluation of engine parameters and heat trainingof engine in the structure of intelligent transport systems.
2016-04-05
Technical Paper
2016-01-1273
Lakshmikanth Meda, Martin Romzek, Yanliang Zhang, Martin Cleary
Although the technology of combustion engines is quite fully developed, the degree of efficiency is considerably low. A large amount of the energy, around 30 %, is lost as exhaust waste heat, and up to 30 % is dissipated in the cooling circuits. This is a reason why thermal recuperation has a great potential for raising the efficiency of combustion engines. In order to meet ever-increasing consumer demand for higher fuel economy, and to conform to more stringent governmental regulations, auto manufacturers have increasingly looked at thermoelectric materials as a potential method to recover some of that waste heat and improve the overall efficiency of their vehicle fleets. Seeking new possibilities to make vehicles greener and more efficient, the industry wants to use the waste heat which passes through the exhaust system almost completely unused in the past.
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
2016-01-0240
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.
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