Kinetic Energy Recovery Research Articles

Feasibility Study on MHEV Application for Motorbikes: Components Sizing, Strategy Optimization through Dynamic Programming and Analysis of Possible Benefits

Reducing CO2 emissions is becoming a particularly important goal for motorcycle manufacturers. A fully electric transition still seems far away, given the difficulties in creating an electric motorcycle with an acceptable range and mass. This opens up opportunities for the application of hybrid powertrains in motorcycles. Managing mass, cost, and volume is a challenging issue for motorcycles; therefore, an MHEV architecture represents an interesting opportunity, as it is a low-complexity and low-cost solution. Firstly, in this work, an adequate sizing of the powertrain components is studied for the maximum reduction in fuel consumption. This is performed by analyzing many different system configurations with different hybridization ratios. A 1D simulation of the motorcycle traveling along the homologation cycle (WMTC) is performed, and the powerunit use strategy is optimized for each configuration using the Dynamic Programming technique. The results are analyzed in order to highlight the impact of kinetic energy recovery and engine load-point shifting on fuel consumption reduction. The results show the applicability of MHEV technology to road motorcycles, thus providing a useful tool to analyze the cost/benefit ratio of this technology. The developed methodology is also suitable for different vehicles once a specific test cycle is known.

Efficient roller-driven elastocaloric refrigerator

Elastocaloric cooling has experienced fast development over the past decade owing to its potential to reshape the refrigeration industry. While the solid-state elastocaloric refrigerant is emission-free, the efficiency of the state-of-the-art elastocaloric cooling systems is not sufficient yet to reduce carbon emissions during operation. In this study, we double the coefficient of performance, the most commonly used efficiency metric, via the synergy of material-level advances in TiNiCu and the system-level roller-driven mechanism capable of recovering kinetic energy. On the materials level, a 125% improvement in coefficient of performance is illustrated in TiNiCu compared to NiTi, empowered by the B2-B19 martensitic transformation with improved lattice compatibility and the grain boundary strengthening from the nanocrystalline structure. On the system level, owing to the properly sized angular momentum in rotating parts, 78% work recovery efficiency is reported, transcending the theoretical limit previously unattainable without kinetic energy recovery. This confluence of materials and mechanical innovations propels elastocaloric cooling systems into a new realm of efficiency and paves the way for their practical application.

The kinetic energy recovery of a buoyancy engine

The kinetic energy recovery of a buoyancy engine

Electric Taxiing System. Kinetic Energy Recovery System as an Electric Taxiing Solution: Economic and environmental analysis: Phenom 300 case study

The aviation industry has thrived in recent years, with a significant increase in passenger numbers, leading to the development of larger aircraft fleets and the expansion of airport infrastructure. In 2019, more than 4.5 billion passengers traveled by airplane, which represents an 80% increase compared to 2009. As a consequence, this growth has also resulted in longer taxiing times for aircraft, increasing fuel consumption and operational costs. The industry's CO2 emissions have quadrupled since the 1960s, with over 1 billion tons released in 2019, contributing to global warming. Given that the improvements being made to current propulsion systems and the production of over 600 million liters of SAF (Sustainable Aviation Fuel) in 2023 do not seem sufficient to meet the ambitious goals set by regulators and operators, the logical solution would be to develop a system capable of moving the aircraft on the ground using alternative, cleaner, and cheaper energies, such as electric power. This paper explores the latest advancements in electric propulsion systems, specifically focusing on external and onboard systems. After the state of the art is established, this paper will cover a case study and propose a new alternative for an onboard system called ETS – Electric Taxiing System. The ETS is a 100% electric system for ground handling operations designed to use only the kinetic energy stored in a battery pack, which is recovered during aircraft landing and braking events. Although there are some studies on this topic, the author considers this paper to be more comprehensive as the results computed here take into account 96 variables, 60 simulations, several flight plans, and real-world data. The case study focuses on the implementation and dimensioning of the ETS, considering electric motor power and torque, and battery capacity for the Embraer Phenom 300. A brief economic and environmental analysis was also conducted, considering the operation of NetJets Europe, the world's leading and largest private jet company.

Energy recovery in automotive systems: A review of regenerative braking, flywheel, thermoelectric, rankin cycle and electric turbo compound

In the backdrop of escalating global vehicle proliferation and the consequent surge in carbon dioxide (CO2) emissions, there is a compelling urgency to innovate energy recovery methods during vehicular operations for heightened energy efficiency and substantial environmental emission reductions. This paper discussed a variety of vehicle technologies to address environmental emissions issues and critically evaluates contemporary energy recovery technologies across three core dimensions: automotive thermal energy conversion, electronic turbine systems (ETC), and kinetic energy recovery systems. By analyzing empirical data encompassing CO2 emission reduction, energy recovery efficiency enhancement, fuel economy improvement, and applicability diversity across vehicle models, the study aims to establish a scientific foundation for continuous vehicular energy efficiency enhancement and emission reduction. This entails a comprehensive investigation of internal combustion engine principles for potential heat energy recovery, juxtaposing conventional and advanced cycles like the Rankine cycle. Moreover, it involves assessing ETC effectiveness in utilizing exhaust energy while acknowledging system complexity and dynamic response challenges. Additionally, the performance disparities of kinetic energy recovery systems like regenerative braking and exhaust energy recovery in distinct operational contexts are examined. By meticulously comparing experimental data, the paper intends to provide a comprehensive assessment of each technologys merits and drawbacks in advancing energy efficiency and emission reduction, try to pick one or more combinations to minimise the impact, thereby guiding future research and application in automotive energy recovery, and contributing to sustainable automotive engineering technology advancement.

REGENERATIVE SHOCK ABSORBERS

Electric vehicles (EVs) have gained popularity as a solution to the fossil fuel crisis and carbon emissions. However, limited range due to battery constraints has been a major obstacle to widespread adoption. Battery management strategies, fast charging, and strategic charging station placement are some of the solutions being explored to address this issue. Another solution is to harness energy from the shock absorbers, which are responsible for filtering vehicle vibrations on rough roads. Research has been conducted since the 1980s on harnessing energy from shock absorbers, and REGENERATIVE SHOCK ABSORBERS have been proposed as a way to harvest the kinetic energy dissipated by suspension vibrations. Studies have shown that REGENERATIVE SHOCK ABSORBERS can produce up to 400W of power at 100 km/h, and can improve the energy harvesting and ride comfort of regenerative vehicle suspensions. Some studies have used electromagnetic methods to generate electric power, while others have used hydraulic methods. The use of regenerative shock absorbers in EVs is a promising solution that has the potential to significantly extend the range of these vehicles. KEYWORDS: Regenerative shock absorber; vehicle suspension; vehicle kinetic energy recovery.

Experimental platform for studying energy regeneration in electric vehicle powertrains

Investigation into the energy consumption in electric vehicles (EVs) plays a pivotal role in determining their autonomy and assessing the electric system performance across diverse operational scenarios. This study focuses on the concept of energy regeneration, encompassing the recovery and storage of kinetic mechanical energy during braking or descent in EVs. Employing control systems in power electronics becomes necessary to establish a seamless workflow across operational quadrants to ensure efficient energy regeneration in an electric machine functioning as both a motor and a generator. To seamlessly integrate new technologies into practical applications, it is essential to conduct thorough evaluations in laboratories prior to deployment. This paper introduces an experimental platform specifically designed to analyze energy consumption and storage in EVs by emulating their powertrains in a controlled laboratory environment. The platform comprises key components for emulating the powertrain of a single-motor electric vehicle with single-axle traction, including a power converter configured in two quadrants, an energy storage system, a primary rotating electric machine, and a mechanically coupled point load torque (another motor). This paper provides a detailed guide on implementing such a laboratory and for facilitating the testing of diverse motor technologies and controllers under varied operational conditions. This comprehensive approach allows for the assessment of electromechanical system efficiency, focusing on both energy recovery and comprehensive control of electric power converters. Validation tests conducted under urban conditions and on steep terrains demonstrate the effectiveness of the platform in analyzing the energy efficiency of both the induction machine and the power controller.

Kinetic energy harvesting for enhancing sustainability of refrigerated transportation

The industry of temperature-controlled transportation has shown significant growth in recent years, and this growth is expected to continue in the future. As the sector expands, it's crucial to focus on reducing energy consumption and greenhouse gas emissions related to transport refrigeration systems to meet the planned decarbonization goals. In this study, the energy and environmental benefits of implementing an electric Kinetic Energy Recovery System (KERS) on a refrigerated light-duty commercial van, equipped with a vapor compression refrigeration (VCR) system, are assessed by means of dynamic simulation. The KERS considered involves a LiFePO4 battery as electricity storage system, a brushless motor-generator unit and a hybrid inverter able to both charge the battery and power the refrigeration system. For each component of the system, i.e. the engine, the alternator, the transmission system and the KERS, the real efficiencies have been considered. The dynamic behaviour of the KERS is simulated by using data obtained by performing a real urban single-delivery 40 km mission, during which the vehicle operating conditions, as well as the electricity demand of the refrigeration system, have been measured. The estimation of the potential benefits of the proposed solution has been performed by comparing the electricity produced by the KERS (and available for use) and the measured energy demand of the refrigeration system.The results have shown that the electricity available for use could cover more than 47% of the total electricity demand. This means that nearly half of the primary energy/fuel consumption can be saved by employing a KERS in refrigerated-light duty vehicles. In particular, emissions savings ranging between 9 and 13 gCO2,e and cost savings between 0.4 and 0.7 c€ per kilometer travelled can be achieved, resulting in an average payback period of 8 years. In addition, when considering the entire useful life of a refrigerated van equal to 10 years, CO2,e savings of 4515–6710 kgCO2,e are obtained.The low complexity of the proposed system and the availability of the components on the market, together with the results obtained by simulation, make using KERS in refrigerated transport a promising solution throughout the decarbonization of the refrigerated transport sector.

Kinetic Energy Recovery from a landing aircraft: Evaluating Onboard Energy Solutions

This paper compares onboard Energy Storage Solutions (ESSs) for a Kinetic Energy Recovery System (KERS) from a landing aircraft. Energy is stored temporarily and reused so that it enables engine-less taxiing. This paper evaluates the choice of onboard Energy Storage Solutions (ESSs) (flywheels, batteries and supercapacitors) for recovering energy during the landing roll and storing it in the device. A design of an ESS with each of the three technologies was made, using commercially available products. The resulting devices are compared on the basis of weight, charging time, discharging time and complexity in retrofitting to existing systems. Results shows that while batteries have the highest energy density and will have the lowest weight, they are unable to charge/discharge quickly enough to satisfy this application. Conversely, supercapacitors have this ability but their low energy density make them heavy which in turn would offer penalty to the aircraft in flight. Flywheels emerge as the most interesting proposition due to their high energy density and fast charging ability, which satisfy the requirements for application.

More Electric Aircraft Conversion to All-Electric During Ground Operations: Battery-Powered Landing Gear Drive System

Raising awareness about environmental issues moves the aerospace industry towards electrification and the corresponding solutions are already present at some airports. However, commercial aircraft are the missing links in claiming the all-electric ground operations. They rely on fossil fuels without any electric alternative due to the technological inability to store large amounts of energy while maintaining low weight of batteries. The issue diminishes if an electric system uses only a fraction of energy normally consumed by the engines and comprises kinetic energy recovery. Accordingly, this paper demonstrates the landing gear drive system for a narrowbody air-plane which has the sustainable and economic means to replace all onboard engines throughout ground operations. The system is simulated in MATLAB/Simulink and leads to the kinematic results which are based on the real drive cycles. The kinematics are subsequently used to estimate the overall on-ground power and energy demand of a more electric aircraft (MEA). The impact is maximized with the components scaled according to performance metrics and two-speed gear ratio optimization. The net fuel advantage is demonstrated for different ground operation modes, taxi times and flight path lengths.

Electric Vehicle Charging from Tramway Infrastructure: A New Concept and the Turin Case Study

The electrification of transport is expected to progressively replace significant shares of light duty mobility, especially in large cities. The European Alternative Fuel Infrastructure Regulation (AFIR) aims to drive the adoption of electric mobility by establishing specific targets for charging point deployment. Innovative charging concepts may complement and accelerate the uptake of this fundamental part of the urban mobility transition. In this paper, one such innovative concept is described and its potential impact is assessed. The core idea involves integrating charging points into existing city tramway infrastructures. Turin’s tramway network is taken as a representative case study. The proposed technical solution encompasses a charging hub powered by four isolated DC/DC converters of 50 kW, directly connected to the DC tramway distribution line. Three of these constitute the heart of a 150 kW charger, while the fourth acts as voltage regulator. This native DC installation greatly simplifies the architecture of the DC chargers. Using a conservative approach, it was estimated that a single recharging station could charge more than 60 vehicles daily. This highly scalable and replicable solution, with the potential for over 100 conversion substations across Italy, would enable the installation of numerous high-power chargers in urban settings. Furthermore, additional benefits could be realized through enhanced recovery of kinetic energy from trams, which is currently dissipated on-board.

Primary Frequency Regulation Strategy Based on Rotor Kinetic Energy of Double-Fed Induction Generator and Supercapacitor

To address the challenge of wind turbines meeting primary frequency regulation requirements, incorporating energy storage devices to handle most of the frequency regulation tasks would result in increased operational costs. When a wind turbine rotor accelerates, it deviates from the maximum power tracking point (MPPT), leading to reduced output while retaining significant rotational kinetic energy. Based on this characteristic, a primary frequency regulation strategy is proposed that coordinates the rotor kinetic energy of a double-fed induction generator (DFIG) with supercapacitors (SCs). Supercapacitors provide power support during low-frequency conditions, while accelerating the wind turbine rotor reduces output during high-frequency conditions. Additionally, continuous attention is given to subsequent frequency changes. In case of short-term, low-frequency conditions, stored kinetic energy is released for power support, establishing a mechanism for wind turbine kinetic energy recovery and release. This mechanism reduces charging and discharging requirements for supercapacitors, extends their service life, and considers both wind turbine frequency regulation requirements and economy. Finally, using MATLAB 2020/Simulink platform allows for the verification of the effectiveness and rationality of this proposed method.

KERS-Inspired Nanostructured Mineral Coatings Boost IFN-γ mRNA Therapeutic Index for Antitumor Immunotherapy.

Tumor-associated macrophage (TAM) reprogramming is a promising therapeutic approach for cancer immunotherapy; however, its efficacy remains modest due to the low bioactivity of the recombinant cytokines used for TAM reprogramming. mRNA therapeutics are capable of generating fully functional proteins for various therapeutic purposes but accused for its poor sustainability. Inspired by kinetic energy recovery systems (KERS) in hybrid vehicles, a cytokine efficacy recovery system (CERS) is designed to substantially augment the therapeutic index of mRNA-based tumor immunotherapy via a "capture and stabilize" mechanism exerted by a nanostructured mineral coating carrying therapeutic cytokine mRNA. CERS remarkably recycles nearly 40% expressed cytokines by capturing them onto the mineral coating to extend its therapeutic timeframe, further polarizing the macrophages to strengthen their tumoricidal activity and activate adaptive immunity against tumors. Notably, interferon-γ (IFN-γ) produced by CERS exhibits ≈42-fold higher biological activity than recombinant IFN-γ, remarkably decreasing the required IFN-γ dosage for TAM reprogramming. In tumor-bearing mice, IFN-γ cmRNA@CERS effectively polarizes TAMs to inhibit osteosarcoma progression. When combined with the PD-L1 monoclonal antibody, IFN-γ cmRNA@CERS significantly boosts antitumor immune responses, and substantially prevents malignant lung metastases. Thus, CERS-mediated mRNA delivery represents a promising strategy to boost antitumor immunity for tumor treatment.

Comprehensive Analysis of Kinetic Energy Recovery Systems for Efficient Energy Harnessing from Unnaturally Generated Wind Sources

Alternative energy is a rapidly expanding research area primarily driven by concerns over pollution caused by inefficient conventional energy sources. However, many developing nations rely heavily on these conventional sources. In response, numerous researchers have focused on developing kinetic energy recovery systems (KERS) to capture and utilize the energy lost due to inefficiency. These KERS can be implemented in various scenarios, such as near railroad tracks, industrial flue stacks, cooling towers, and air conditioning outlets. The primary objective of this paper is to critically and comprehensively evaluate the research conducted on the development of these systems. The review reveals that the wind speed in the studied cases ranged between 15 and 22 m/s, providing a consistent and theoretically maximum potential higher than any location worldwide. Furthermore, the impact of these systems on the Betz limit, as well as their drawbacks and crucial advancements necessary for practical implementation, have been thoroughly assessed. This paper contributes to the existing body of knowledge by presenting a comprehensive analysis of the research conducted on KERS development. It highlights the potential of these systems in harnessing untapped energy sources and identifies key areas that require further attention for successful practical application.

Analysis of Kinetic Energy Recovery Systems in Electric Vehicles

The recovery of kinetic energy (KER) in electric vehicles was analyzed and characterized. Two main systems were studied: the use of regenerative brakes, and the conversion of potential energy. The paper shows that potential energy is a potential source of kinetic energy recovery with higher efficiency than the traditional system of regenerative brakes. The study compared the rate of KER in both cases for a BMWi3 electric vehicle operating under specific driving conditions; the results of the analysis showed that potential energy conversion can recover up to 88.2%, while the maximum efficiency attained with the regenerative brake system was 60.1%. The study concluded that in driving situations with sudden and frequent changes of vehicle speed due to traffic conditions, such as in urban routes, the use of regenerative brakes was shown to be the best option for KER; however, in intercity routes, driving conditions favored the use of potential energy as a priority system for KER.

Investigation of energy dissipation of an H-type vertical axis wind turbine based on entropy production theory

In vertical axis wind turbine (VAWT) research, amount studies have been conducted about the flow field around the blades, but the effect of blade tip vortex was not revealed clearly. The present study emphasized on the effect of blade tip vortex on energy loss in wake region and employed entropy production theory to determine where and how energy loss generates quantitatively. The numerical simulation was conducted for the VAWTs versus various tip speed ratio (TSR) conditions, and the numerical results were analyzed by entropy production method. The energy loss calculated by entropy production theory in VAWTs flows increases with TSR increasing. The distribution of entropy production rate (EPR) in wake region was asymmetrical due to the influence of blade tip vortex diffusion downstream and two fluctuation peaks appeared on EPR curves. The energy loss coefficient was defined to represent the energy deficit and kinetic energy recovery in wake region quantitatively. Generally, the energy loss coefficient was reduced to 0.1 between 8D to 9D in wake region and was equal to 0.1051 at x = 8D under optimal condition TSR = 2.19. The present study can guide configuration optimization of VAWTs to improve wind energy utilization and revenue of wind farms.

A Flywheel-Based Regenerative Braking System for Railway Vehicles

Abstract Regenerative braking is a technique that employs electric motors to convert the dynamic mechanical energy from the motor’s spinning rotor and any attached loads into electricity. However, such a type of regenerative braking can only slow but not stop the vehicle because there is too little energy to excite the motor acting as a generator at low speeds. Therefore, this paper presents a unique flywheel-based regenerative braking system for railway vehicles. This system is supposed to meet high safety and comfort expectations in all operating conditions. The braking action control of this system should allow braking of empty or loaded vehicles according to load, the anti-blockage braking action of wheels and prevent wheel-slide during braking or wheel slip during acceleration. The new regenerative braking system under development, like any kinetic energy recovery system, requires the application of continuously variable transmission. The essence of the new solution is to design and build this type of variable transmission using only one planetary gear controlled through the powertrain control module for an electric motor cooperating concurrently. This paper describes complete modelling and simulation realisation on a closed-loop servomotor drive, which cooperates with the variable transmission of the regenerative braking system based on the Scilab/Xcos environment.

Systematic modeling of complex time-variant gear systems using a Power-Oriented approach

This paper addresses a methodology for the systematic modeling of complex gear systems. The methodology is based on the use of a unified general model, working for all complex gear systems: time-variant as well as time-invariant, having parallel or oblique rotation axes. The model equations are automatically written following the outlined procedure and applying the presented algorithms, making this approach less prone to mistakes with respect to other approaches. Next, a reduced model assuming rigid gear connections and introducing no loss of information is proposed, which directly gives the kinematic relations between the gears angular speeds and input torques. In order to show some case studies, the proposed methodology is applied to three systems of interest for vehicle dynamics and powertrain modeling. The considered case studies are a differential structure having a bevel gearing system with non-perpendicular gear shafts, a vehicle differential and a full toroidal variator, which is suitable for applications such as KERS (Kinetic Energy Recovery System) and IVT (Infinitely Variable Transmission). Furthermore, the control of a full toroidal variator acting as a KERS with reference to an automotive case study and the comparison of the proposed modeling methodology with two other approaches are addressed.

Retracted: Research on Kinetic Energy Recovery of Energy Vehicle ABS Solenoid Valve Based on the ELM Deep Learning Model.

[This retracts the article DOI: 10.1155/2022/6571085.].

Introductory Analysis of Spark Ignition Engine and Extensively Implemented Electric Alternatives

Energy crises and climate change lead to restricted standards of emission and energy consumption in regular road vehicles. Combustion method, ignition time, and injection time are engine development priorities. Optimal injection and ignition timing at 1600 rpm can save 10% on brake fuel. Perfect injection and ignition timing reduce heat loss and emissions. Various approaches to reducing transportation emissions and energy were implemented. Plug-in electric vehicles and hydrogen fuel cell vehicles (HFCV) were eliminated because of the lack of charging and refilling facilities. Mild hybrid energy recovery devices are considered straightforward and effective. Because of its effectiveness and longevity, Kinetic Energy Recovery System (KERS) is the most popular hybrid system in road automobiles. Future road energy recovery systems may include heat energy recovery methods and solar panels. However, electric vehicles with regenerative technologies own the highest energy efficiency among all the proposed solutions with the advantage of no pollution during the operation.