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2015-01-14
Technical Paper
2015-26-0044
Sambhaji Keshaw Jaybhay, Prasanna Nagarhalli, Suresh Tadigadapa, Sangeet Hari Kapoor
Context- In order to enhance fuel efficiency in buses an energy efficient air conditioning system should be deployed. This will lead to reduced parasitic load on the engine and translate into direct fuel saving. Fuel prices are increasing day by day; along with rapid depletion of fuel sources. Alternate fuels like CNG need investments in infrastructure, which is not available easily everywhere. Therefore fuel saving is vital. In case of air conditioned vehicles, the parasitic load mainly consists of power consumed by air conditioning compressor to pump the refrigerant and by blower motors and condenser fans for movement of conditioned air and heat removal respectively. Furthermore roof mounted bus air conditioning systems weigh in the range of 150-220kg (approx.) adding to the payload Necessity- Now days, most mid-size air conditioned buses are equipped with aftermarket solutions.
2015-01-14
Technical Paper
2015-26-0234
Ramesh Pathuri, Yuvraj Patil, Prasanna Vyankatesh Nagarhalli
During early phases of vehicle program, evaluation of Air Conditioning (AC) system for its performance (time to comfort) and power consumption has become vital and hence simulation tools have gained tremendous importance. A 1D simulation model can be introduced early in the design process to evaluate several AC system configurations and parametric studies at different test conditions and which results in reduced experimental work. This paper presents a method for AC cool down simulation of passenger car with multi air zone cabin model in KULI. This approach allows the prediction of zone wise (head, body and foot) temperature and humidity distribution in the cabin for parameter studies for transient analysis. The same cabin model can deal with multiple inlets into the cabin, solar radiation, and recirculation for pre-defined cabin types.
2015-01-14
Technical Paper
2015-26-0045
Rico Baumgart, Joerg Aurich, Jan Ackermann, Christoph Danzer
The development of an energy efficient air conditioning system for electric vehicles is an ever increasing challenge, because the cooling as well as the heating of the passenger cell reduces the cruising range dramatically. Almost always the compressor of the air conditioning system in electric cars is a scroll compressor with a separate electric motor and appropriate power electronics. However, this solution is critical in terms of the installation space, the weight and also the costs. Therefore, IAV develops innovative and energy efficient drivetrain structures for electric vehicles, which integrate the motor of the air conditioning compressor directly into the drivetrain of the vehicle. Thus it is possible to switch off the compressor motor and to use the main motor for the propulsion of the air conditioning compressor at certain driving situations. As a result the operating point of the main motor can be shifted to a better efficiency.
2015-01-14
Technical Paper
2015-26-0196
Soujanya C, V Sundaram, Sathish Kumar S
Cooling system is one of the important systems of an Engine to maintain the optimum temperatures across engine and its components. Analysis of cooling system at initial phase of product development will help in optimum design of the system. Simulation plays a vital role in optimum design. In the System level simulation it is important to accurately model and discretize the components in the system in order to achieve optimum system level flow balancing and flow prediction. As engine coolant jacket is the major contributor of pressure drop in cooling system, its modelling strategy will have high influence on results predictions across the system. Simulation of engine cooling system with Split engine coolant water jacket is challenging. It is difficult to achieve the simulation results close to bench test due to complexity of the system.
2015-01-14
Technical Paper
2015-26-0026
Suresh Kumar Gurusamy, Sateesh Kumar r, Janga Sridhar Reddy, P Chitnis
At present, on average, two thirds of the fuel energy consumed by an engine is wasted through the exhaust gases and the coolant. Recovering & utilizing, much of that wasted energy can provide a significant increase in overall energy efficiency. Several technologies like Organic Rankine Cycle, Thermo Electrics & turbo-generator are being experimented to recover the waste heat energy. In the present work, a turbo-generator system is designed and developed for additional 3 percent power output, from exhaust heat in the form of electricity. A simple model of the system is developed and the amount of energy that can be recovered using the system is estimated. This theoretical model is verified by testing a turbocharger in series with the existing turbocharger. Results show that the turbo-generator system can improve the engine fuel economy upto 3 % at engine full load operating conditions and 1-2 % at part load conditions.
2014-11-23
WIP Standard
AS8040C
This SAE Aerospace Standard (AS) covers combustion heaters used in the following applications: a. Cabin heating (all occupied regions and windshield heating) b. Wing and empennage anti-icing c. Engine and accessory heating (when heater is installed as part of the aircraft) d. Aircraft de-icing
2014-11-18
Magazine
Oil debris monitoring in aero engines In a gas turbine engine, small particles or "chips" are generated at the point of wear, serving as an advanced warning that catastrophic failure will occur if the wear is not addressed. Health monitoring systems, such as oil debris monitoring, are used to find these small particles so that the wear can be resolved before it's too late. Indigenous powertrain development Customer needs and expectations on drivability, fuel economy, and safety has pushed Indian and multinational OEMs to think about the development of powertrains and gearboxes for local needs with global standards. The next wave of crash simulation As computing speed has improved and software itself has made significant speed and performance gains with each release, modeling tools are now quick enough to build high-quality, large, high-detail vehicle models in a very efficient manner.
2014-11-11
Journal Article
2014-32-0044
Simone Vezzù, Carlo Cavallini, Silvano Rech, Enrico Vedelago, Alessandro Giorgetti
Abstract The deposition of thick, pore-free, high-performance copper alloy matrix composite coatings is a topic of interest for several industrial applications, including friction materials, high-strength electrical contacts, and welding electrodes, among others. This study investigates the use of cold spray to deposit CuCrZr/Al2O3 cermet coatings on aluminum alloy 6060. The objective is to integrate copper-based materials with aluminum-based materials, ensuring a high degree of mechanical and thermal contact, using a low temperature process that does not adversely affect the properties of the base materials. This technique can be used to produce integral coolers and aluminum-based bearings for automotive and motorcycle applications. Fused and crushed alumina and gas-atomized CuCrZr powder blends have been used as initial feedstocks, with compositional weight ratios of 65/35 and 80/20 (ceramic/metal).
2014-11-11
Journal Article
2014-32-0050
Tomokazu Nomura, Koichiro Matsushita, Yoshihiko Fujii, Hirofumi Fujiwara
Abstract For detailed temperature estimates in the engine of a running motorcycle, newly researches were conducted on the method for calculation of temperature distribution using a three-dimensional (3D) thermal conductivity simulation after calculating the total balance of heat generation and heat dissipation of the engine using a one-dimensional (1D) thermal simulation. This project is targeted at air-cooled engines in which the cooling conditions vary significantly depending on the external shapes of the engines and the airflow around them. The heat balance is calculated using the 1D thermal simulation taking into account all the routes and processes for dissipation to the atmosphere of the heat that is generated by the combustion in the engine. The 1D engine cycle simulation is applied to calculate the heat transmission to the engine from the combustion. For the calculation of heat transfer within the engine, the engine components are converted to a one-dimensional model.
2014-11-11
Journal Article
2014-32-0080
Jens Steinmill, Ralf Struzyna
Abstract At a micro-CHP unit the target size of the engine controller is not mechanical torque but thermal and mechanical power. Accordingly, these demands must be implemented by the engine controller. This means that on the one hand a mechanical demand is answered under the boundary condition of the highest actual efficiency and that on the other hand thermal demands have to be processed. Since the thermal- and mechanical power output is coupled with the actual efficiency, exceeding the nominal load of the thermal power, the actual efficiency can be regulated in order to answer the demand. This can be done in consideration of the maximum achievable actual efficiency. Limits are set by the combustion stability and thermal protection functions. The functions are modelled with Matlab/Simulink and the ECU code for a rapid control prototyping system is generated. A dynamic engine test bed for internal combustion engines up to 12 kW was built to verify the motor control functions.
2014-11-11
Journal Article
2014-32-0108
Sejun Lee, Kyohei Ozaki, Norimasa Iida, Takahiro Sako
Abstract Recently, a potentiality of Dedicated EGR (D-EGR) concept SI engine has been studied. This concept engine had four cylinders and operated with exhaust gas supplied from the single cylinder to the intake manifold. Compared with conventional SI engines, it was able to increase thermal efficiency and decrease CO, HC, and NOx emission by the high D-EGR ratio 0.25. In this study, numerical analysis of a SI engine with D-EGR system with various D-EGR ratios was conducted for detailed understanding the potentiality of this concept in terms of thermal efficiency and NOx emission. #1 cylinder of assumed engine was used as D-EGR cylinder that equivalence ratio varied from 0.6 to 3.4. Entire exhaust gas from #1 cylinder was recirculated to the other cylinders. The other cylinders run with this exhaust gas and new premixed air and fuel with various equivalence ratios from 0.6-1.0.
2014-11-01
Journal Article
2014-01-9129
Filip Nielsen, Åsa Uddheim, Jan-Olof Dalenbäck
Abstract Fuel consumption of vehicles has received increased attention in recent years; however one neglected area that can have a large effect on this is the energy usage for the interior climate. This study aims to investigate the energy usage for the interior climate for different conditions by measurements on a complete vehicle. Twelve different NEDC tests in different temperatures and thermal states of the vehicle were completed in a climatic wind tunnel. Furthermore one temperature sweep from 43° to −18°C was also performed. The measurements focused on the heat flow of the air, from its sources, to its sink, i.e. compartment. In addition the electrical and mechanical loads of the climate system were included. The different sources of heating and cooling were, for the tested powertrain, waste heat from the engine, a fuel operated heater, heat pickup of the air, evaporator cooling and cooling from recirculation.
2014-10-24
Standard
J1535_201410
This SAE Standard establishes uniform test procedures for the defrosting systems of off-road, self-propelled work machines used in construction, general purpose industrial, agricultural, and forestry machinery as referenced in table one of this document. It includes tests that can be conducted with uniform test equipment in commercially available laboratory facilities, as well as in an appropriate outdoor environment.
2014-10-13
Technical Paper
2014-01-2596
Bo Hu, Colin Copeland, Chris Brace, Sam Akehurst, Alessandro Romagnoli, Ricardo Martinez-Botas, J.W.G Turner
Abstract Engines equipped with pressure charging systems are more prone to knock partly due the increased intake temperature. Meanwhile, turbocharged engines when operating at high engine speeds and loads cannot fully utilize the exhaust energy as the wastegate is opened to prevent overboost. The turboexpansion concept thus is conceived to reduce the intake temperature by utilizing some otherwise unexploited exhaust energy. This concept can be applied to any turbocharged engines equipped with both a compressor and a turbine-like expander on the intake loop. The turbocharging system is designed to achieve maximum utilization of the exhaust energy, from which the intake charge is over-boosted. After the intercooler, the turbine-like expander expands the over-compressed intake charge to the required plenum pressure and reduces its temperature whilst recovering some energy through the connection to the crankshaft.
2014-10-13
Technical Paper
2014-01-2594
Xinyu Wang, Yadong Deng
Abstract Automotive exhaust-based thermoelectric generator (TEG), which effectively converts exhaust thermal energy into electrical energy, can gradually improve the utilization efficiency of energy. The heat exchanger of TEG is one of the most important components for heat transfer, so as to realize energy saving and emission reduction. Hence, its configuration and thermal performance should be intensively studied. In this paper, a new configuration of heat exchanger, whose heat transfer area is regular octagon, is designed in comparison with the pervious rectangle one. In order to improve average temperature and thermal distribution uniformity, typical CFD software named FLUENT is used to simulate the multi-coupling of temperature - fluid - solid, and the temperature distribution on heat transfer area is gained. Moreover, the temperature distribution will be analyzed to evaluate the merits and weaknesses of configuration and thermal performance.
2014-10-13
Technical Paper
2014-01-2600
Le-zhong Fu, Zhijun Wu, Liguang Li, Xiao Yu
Abstract The present work discusses a novel oxyfuel combustion method named internal combustion rankine cycle (ICRC) used in reciprocating engines. Water is heated up through heat exchanger by exhaust gas and engine cooling system, and then injected into the cylinder near top dead center to control the combustion temperature and in-cylinder pressure rise rate, meanwhile to enhance the thermo efficiency and work of the combustion cycle. That is because injected water increases the mass of the working fluid inside the cylinder, and can make use of the combustion heat more effectively. Waste heat carried away by engine coolant and exhaust gas can be recovered and utilized in this way. This study investigates the effect of water injection temperature on the combustion and emission characteristics of an ICRC engine based on self-designed test bench. The results indicate that both indicated work and thermal efficiency increase significantly due to water injection process.
2014-10-13
Journal Article
2014-01-2857
Jose Serrano, Pablo Olmeda, Francisco Arnau, Artem Dombrovsky
Abstract These days many research efforts on internal combustion engines are centred on optimising turbocharger matching and performance on the engine. In the last years a number of studies have pointed out the strong effect on turbocharger behaviour of heat transfer phenomena. The main difficulty for taking into account these phenomena comes from the little information provided by turbocharger manufacturers. In this background, Original Engine Manufacturers (OEM) need general engineering tools able to provide reasonably precise results in predicting the mentioned heat transfer phenomena. Therefore, the purpose of this work is to provide a procedure, applicable to small automotive turbochargers, able to predict the heat transfer characteristics that can be used in a lumped 1D turbocharger heat transfer model. This model must be suitable to work coupled to whole-engine simulation codes (such as GT-Power or Ricardo WAVE) for being used in global engine models by the OEM.
2014-10-13
Journal Article
2014-01-2592
Dhaminda Hewavitarane, Sadami Yoshiyama, Hisashi Wadahama, Xin Li
Abstract High temperature liquids held in a subcooled state are capable of storing large amounts of energy and then explosively releasing this energy when depressurized in a phase change process known as “Flashing”. The rapid volume expansion that results from this flashing has been harnessed to drive an expansion engine working on a cycle called “The Superheated Liquid Flash, Boiling” (S.L.F.B) cycle. The first stage showed that multiphase convective boiling of the unflashed water off the heated walls of the expansion unit supplemented the Flash work output. Furthermore, Flashing was seen to improve the effectiveness of convective boiling off the walls. The results were shown to be repeatable in a modified piston engine. Convective boiling was again shown to be able to supplement the power output under specific conditions.
2014-10-01
Magazine
Propulsion: Energy Sources Flying on vegetation Avionics/Electronics Avionics heat up, in a good way Unmanned Vehicles Reaching the benchmark in secure unmanned vehicle software Thermal Management Submersion and directed flow cooling technology for military applications RF & Microwave Technology Airborne antenna considerations for C-Band telemetry systems Software-designed system improves wireless test speed and coverage
2014-09-30
Technical Paper
2014-01-2395
Gurunathan Varun Kumar, Meer Reshma Sheerin, Vedachalam Saravana Prabu, Kallikadan Jean, Chaitanya Rajguru, Murugesan Dinesh, Andrew Croft
Abstract Automotive climate control systems are evolving at a rapid pace to meet the overall vehicle requirements and the user expectations for comfort and convenience. This poses a challenge in the product development life cycle of multi-platform vehicle systems with respect to development time and optimal performance in the Heating, Ventilation and Air Conditioning (HVAC) system. This paper proposes rapid HVAC plant model design and development using simplified one-dimensional (1D) simulation models for fast simulations. The specific accuracy limitations of such a simplified model are overcome using limited three-dimensional computational fluid dynamics (3D CFD) modelling. User-level control strategy is developed in an integrated simulation environment that includes a reference 1D model and a control algorithm simulator. The simulation data is used to study and analyse the temperature and airflow distribution in the system.
2014-09-30
Technical Paper
2014-01-2343
Manfei Bai, Gangfeng Tan, Yadong Deng, Wenying Wang, Hui Yan
Abstract To make full use of engine exhaust heat and further improve the utilization of the energy efficiency of the heavy truck, thermoelectric module is used to contribute to thermoelectric power generation. The hot-end temperature of the module varies with the engine operating condition because it is connected with the exhaust pipe. The cold-end of the thermoelectric module is mainly cooled by engine cooling system. Increasing the temperature difference between the hot-end and cold-end of the thermoelectric module is a good way to improve the thermoelectric conversion efficiency. For the poor controllability of the hot-end temperature of the thermoelectric module, this study puts forward by lowering the cold-end temperature of the thermoelectric module so as to ensure the improvement of the thermoelectric conversion efficiency. The cooling circle for the cold-end of the thermoelectric module which is independent of the engine cooling system is built.
2014-09-30
Technical Paper
2014-01-2341
Salvador Sermeno, Eric Bideaux, Tessa Morgan, Duc Nguyen
Abstract Vehicle thermal management covers the engineering field of solutions that maintain the complete vehicle in acceptable operating conditions regarding component and fluid temperatures in an engine. The maximum efficiency rating of a Diesel engine reaches up to 45%. In order to improve the fuel efficiency of the vehicle one can reduce the losses generated by the cooling system. Ideally, the full motive force of the engine should be used for propulsion and new and more efficient energy sources have to be explored to power the secondary systems (cooling, compressed air…). This paper introduces a dynamic programming algorithm which is used to determine the maximum gains during operation for a given architecture of the cooling system of a Heavy Duty Truck. The algorithm, based in Bellman principle, will determine the best control trajectory for the pump and the fan according to energetic and control goals (fuel economy, regulation of temperature…).
2014-09-30
Technical Paper
2014-01-2406
Marco Carriglio, Alberto Clarich, Rosario Russo, Enrico Nobile, Paola Ranut
Abstract The main purpose of this study is the development of an innovative methodology for Heat Exchangers (HE) design to replace the conventional design procedures. The new procedure is based on the definition of a software package managed by modeFRONTIER, a multi-objective optimization software produced by ESTECO, able to create HE virtual models by targeting several objectives, like HE performance, optimal use of material, HE minimal weight and size and optimal manufacturability. The proposed methodology consists first in the definition of a workflow for the automatic CFD simulation of a parametric model of a periodic HE cellular element.
2014-09-30
Journal Article
2014-01-2325
Michael Franke, Shirish Bhide, Jack Liang, Michael Neitz, Thomas Hamm
Abstract Exhaust emission reduction and improvements in energy consumption will continuously determine future developments of on-road and off-road engines. Fuel flexibility by substituting Diesel with Natural Gas is becoming increasingly important. To meet these future requirements engines will get more complex. Additional and more advanced accessory systems for waste heat recovery (WHR), gaseous fuel supply, exhaust after-treatment and controls will be added to the base engine. This additional complexity will increase package size, weight and cost of the complete powertrain. Another critical element in future engine development is the optimization of the base engine. Fundamental questions are how much the base engine can contribute to meet the future exhaust emission standards, including CO2 and how much of the incremental size, weight and cost of the additional accessories can be compensated by optimizing the base engine.
2014-09-26
WIP Standard
AIR4766/2A
This SAE Aerospace Information Report (AIR) provides information on aircraft cabin air quality, including: - Airborne contaminant gases, vapors, and aerosols. - Identified potential sources. - Comfort, health and safety issues. - Airborne chemical measurement. - Regulations and standards. - Operating conditions and equipment that may cause aircraft cabin contamination by airborne chemicals (including Failure Conditions and normal Commercial Practices). - Airborne chemical control systems. It does not deal with airflow requirements.
2014-09-17
WIP Standard
J2670
This SAE standard applies to any and all additives and chemical solutions intended for aftermarket use in the refrigerant circuit of vehicle air-conditioning systems with belt-driven compressors, except as noted below. This standard provides testing and acceptance criteria for determining the stability and compatibility of additives and flushing materials (solutions) with A/C system materials and components, that may be intended for use in servicing or operation of vehicle air conditioning systems. This standard does not provide test criteria for additive, compressor lubricant, or flushing solution effectiveness; such testing is the responsibility of the additive and/or solution manufacturer/supplier. This standard does not cover additives or flushing materials for electrically driven compressors. The use of additives with electrically driven compressors might cause electrical shorting and compressor failure.
2014-09-17
WIP Standard
J2297
This SAE Standard applies to dyes intended to be introduced into a mobile air-conditioning system refrigerant circuit for the purpose of allowing the application of ultraviolet leak detection. In order to label any product(s) they shall meet SAE J2297, and the certification process as described in SAE J2911 must be followed and the documentation described in the appendix shall be submitted to SAE.
2014-09-16
Technical Paper
2014-01-2225
Hidefumi Saito, Shoji Uryu, Norio Takahashi, Noriko Morioka, Hitoshi Oyori
Abstract To improve an energy optimization issue of ECS for MEA, we propose our concept in which ACS is replaced with VCS. A VCS is generally evaluated as auxiliary or limited cooling system of an aircraft. Cooling demand of commercial aircraft usually becomes large due to ventilation air at hot day conditions. In case of using conventional VCS for whole cooling demand, the ECS becomes too heavy as aircraft equipment. Though ACS's light weight is advantageous, the issue that VCS will be available for aircraft ECS is important for saving energy. ECS of commercial aircraft should work for three basic functions, i.e. pressurization, ventilation, and temperature control. The three functions of the ECS for bleed-less type of MEA can be distributed among equipment of the ECS. MDFAC works for pressurization and ventilation. Therefore, we should select appropriate system for only temperature control.
2014-09-16
Technical Paper
2014-01-2224
Stephen Emo, Jamie Ervin, Travis E. Michalak, Victor Tsao
Abstract Numerous previous studies have highlighted the potential efficiency improvements which can be provided to aircraft thermal management systems by the incorporation of vapor cycle systems (VCS), either in place of, or in conjunction with, standard air cycle systems, for providing the needed thermal management for aircraft equipment and crews. This paper summarizes the results of a cycle-based VCS control architecture as tested using the Vapor Cycle System Research Facility (VCSRF) in the Aerospace Systems Directorate of the Air Force Research Laboratory at Wright-Patterson Air Force Base. VCSRF is a flexible, dynamic, multi-evaporator VCS which incorporates electronic expansion valves and a variable speed compressor allowing the flexibility to test both components and control schemes. The goal of this facility is to reduce the risk of incorporating VCS into the thermal management systems (TMS) of future advanced aircraft.
2014-09-16
Technical Paper
2014-01-2190
Michael Ellis, William Anderson, Jared Montgomery
Under a program funded by the Air Force Research Laboratory (AFRL), Advanced Cooling Technologies, Inc. (ACT) has developed a series of passive thermal management techniques for cooling avionics. Many avionics packages are often exposed to environment temperatures much higher than the maximum allowable temperatures of the electronics. This condition prevents the rejection of waste heat generated by these electronics to the surrounding environment and results in significant ambient heat gain. As a result, heat must be transported to a remote sink. However, sink selection aboard modern aircraft is limited at best. Often, the only viable sink is aircraft fuel and, depending on mission profile, the fuel temperature can become too high to effectively cool avionics. As a result, the electronic components must operate at higher than intended temperatures during portions of the mission profile, which reduces component lifetime and significantly increases the probability of failure.
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