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Air-conditioning (AC) is an important sub-system in electric vehicles (EVs). AC is responsible for the highest energy consumption among all the auxiliary systems. As the energy is delivered by the batteries, the power consumption for air-conditioning can imply a significant reduction of the vehicle autonomy. Given the actual state of the art and the temperature and power requirements, electrically driven compressors are the most feasible solution. However, vapour-compression systems are reaching their maximum efficiency. Using innovative technologies can improve the performance of standard systems and hereby increase the vehicle autonomy. This paper presents the first steps in the design of a magnetocaloric air-conditioner for an electric minibus. The system will include two reversible magnetocaloric heat pumps, one in the front part of a minibus and one on the rear. The heat rejection system of the power electronics will be coupled to the air-conditioning system.

Among all the auxiliary components in conventional and electric vehicles, air-conditioning (AC) systems present the highest energy consumption. In fully electrical vehicles (FEVs), the heating of the cabin becomes an additional challenge as there is less waste heat available. Therefore, a careful design of the air-conditioning system and of the operation strategies is necessary to reach a reasonable FEV autonomy without compromising the thermal comfort. This paper presents a tool for the design, analysis and optimization of an efficient air-conditioning system for an electric minibus. It consists of dynamic models of each component of the system that have been developed and fully validated individually. Finally, they have been coupled together to simulate the overall vehicle performance of the vehicle in MATLAB-SIMULINK. The core of the system is a water-to-water reversible heat pump with a variable speed compressor.

In this paper a model for Automotive Air Conditioning evaporators is presented, including a comparison between calculated and measured results for two different types of evaporator: tube and fins and plate and fins. The development of the model has been carried out by the Universidad Politécnica de Valencia in co-operation with the Universidad Politécnica de Catalunya and two companies: FASA-RENAULT and FRAPE-BEHR, under a research project supported by the Spanish Agency for R&D: CICYT. The input data for the model are the HEX geometry and the inlet conditions and mass flow rate of both flows. Then the model calculates the outlet conditions and all the performance parameters. The developed model is able to take into account the following aspects of the HE: Tube or plate evaporators as well as any flow configuration: parallel, counter-flow, cross-flow and multi-pass.

In this paper a torque strategy used by RENAULT for the control of a spark ignition engine is presented. With this new strategy for engine control, it was necessary to develop a new motorized butterfly valve. The design and development of this element is described in the paper. This research was carried out through the application of both modeling techniques using computational tools and experimental techniques on the steady flow rig and the engine bench.

This paper presents the main conclusions of the project carried out by the Department of Advanced Studies in Control of Engines of RENAULT and the group IMST of the Departamento de Termodinámica Aplicada de la Universidad Politécnica de Valencia. The main objectives of this Project was: The characterization of the camless engine prototype by means of the modeling for different engine speeds and loads. The determination of the influence of the external operation conditions on the performance of a prototype of a camless engine, by means of the calculation with the program ECARD.

The present concern in the reduction of CO2 emissions occasioned by heavy duty trucks is leading to a technological evolution, among others, in powertrain electrification. Towards this objective, the EU has funded the project GASTone targeting the development of a new powertrain concept based on the energy recovery from the exhaust gases and kinetic losses in order to make possible the electrification of the main auxiliaries. This new concept will follow a cascade approach in which the exhaust gases energy will be recovered by the integration of an advanced thermoelectric generator followed by a turbo-generator. This system will be combined with a smart kinetic energy recovery device which will recover the energy losses in the deceleration periods of the vehicle. The recovered energy will be used in the electrified auxiliaries.

The heating and cooling systems are an important issue in the development of fully electric vehicles (FEVs). On the contrary to vehicles with thermal engines, in FEVs there is almost no waste heat available for the heating of the cabin or for the window de-icing and defogging. The cooling of the cabin also demands a large amount of energy. Due to the high power consumption, the heating and cooling of FEVs is a compromise between thermal comfort and vehicle range. The aim of this work is to present the European project ICE (2010-2014) [1] which focuses on the development of an efficient air-conditioning and heating system based on a magneto-caloric heat pump and on a new system architecture to fulfill the thermal comfort requirements of an electric minibus. The system will be installed and demonstrated in a Daily Electric Mini-bus from IVECO-ALTRA.

Nowadays, more than 50% of the fuel energy is lost in CNG Engines. While efforts to increase their efficiency have been focused mainly on the improvement of the combustion process, the combustion chamber and the reduction of friction losses, heat losses still remain the most important inefficient factor. A global strategy in which several energy recovery strategies are implemented could lead to engine improvements up to 15%. Therefore, the development of accurate models to size and predict the performance of the integrated components as well as to define an optimized control strategy is crucial. In this contribution, a model to analyze the potential of a new powertrain based on the electrification of the main auxiliaries, the integration of a kinetic energy recovery system and the exhaust gases heat recovery through a thermoelectric generator and a turbo-component is presented.