Analysis of an Internal Combustion Engine Using Porous Foams for Thermal Energy Recovery

To promote the energy utilization efficiency of internal combustion engine, the approach of electronically controlled turbocharger (ECT) for IC engine exhaust gas energy recovery was investigated by the method of test coupling with numerical simulation. First, the tests for turbocharged gasoline engine and high-speed motor were conducted so as to provide experimental data for numerical simulation. Then, the simulation model of ECT engine was built and calibrated, and the working processes of ECT engine were simulated. The results show that the recovered exhaust gas energy by ECT increases with the decrease of by-pass valve opening due to the rising of exhaust gas mass flow rate, but the pumping loss also ascends; limited by the original engine turbocharger map, the engine working points are beyond turbine map when the by-pass valve opening increases to a certain degree. To further improve the energy recovery potential of ECT, a larger turbine was rematched, and the working processes of ECT engine under the whole operating conditions were resimulated. The results indicate that engine exhaust gas energy cannot be recovered by ECT in low-load and low-speed area due to the low exhaust gas pressure. In the effective working area, as the load and speed ascend, both the recovery efficiency of ECT and the utilization efficiency of exhaust gas energy increase, and their maximum values reach 8.4% and 18.4%, respectively. All those demonstrate that ECT can effectively recover engine exhaust gas energy.

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An approach for exhaust gas energy recovery of internal combustion engine: Steam-assisted turbocharging

Energy Conversion and Management ◽

10.1016/j.enconman.2014.05.067 ◽

2014 ◽

Vol 85 ◽

pp. 234-244 ◽

Cited By ~ 22

Author(s):

Jianqin Fu ◽

Jingping Liu ◽

Banglin Deng ◽

Renhua Feng ◽

Jing Yang ◽

...

Keyword(s):

Internal Combustion Engine ◽

Energy Recovery ◽

Combustion Engine ◽

Internal Combustion ◽

Exhaust Gas

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INCREASING THE EFFICIENCY OF INTERNAL COMBUSTION ENGINES: HEAT RECOVERY FROM EXHAUST GASES BY THERMOELECTRIC EFFECT

Istituto Lombardo - Accademia di Scienze e Lettere - Incontri di Studio ◽

10.4081/incontri.2018.380 ◽

2018 ◽

Author(s):

Mauro Francesco Sgroi

Keyword(s):

Particulate Matter ◽

Internal Combustion Engine ◽

Co2 Emissions ◽

Thermal Energy ◽

Internal Combustion Engines ◽

Combustion Engine ◽

Internal Combustion ◽

Medium Size ◽

Combustion Engines ◽

Exhaust Gases

The concern related to global warming is generating a legislative pressure on reducing CO2 emissions that is forcing automotive industry to find alternative and more efficient solutions to internal combustion engines. In Europe, the current regulation for passenger vehicles limits the CO2 emissions calculated as fleet average to 130 g/km and fix a target value of 95 g/km to be achieved by 2021. Car manufacturers will have to pay heavy penalties for each registered vehicle exceeding the CO2 limits (€95 per exceeding gram by 2019). Concurrently, the regulations on toxic emissions (CO, NOx, unburned hydrocarbons, particulate matter) is also becoming more and more stringent and requires complex and costly abatement systems to respect the strict limitations imposed on NOx and particulate matter emissions. On the other hand, zero emission electric vehicles, based on batteries, are still not mature enough for a replacement of the internal combustion engine in extra-urban applications, since they are not able to guarantee the driving range required by customers. Hydrogen fuelled vehicles, could meet the same performance of conventional cars, but the cost of materials used in the fuel cell stack is preventing the penetration into the market. Therefore, even though characterized by low energy efficiency, the internal combustion engine will remain, in the short-medium term, the reference technology for the transport industry but the environmental regulations will impose its hybridization with electric systems. Hybrid architectures allow circulating in electric mode in urban areas, limiting the local pollution, and increase the efficiency of the car through energy recovery during breaking phases. An energetic analysis of conventional internal combustion engine reveals that about 70% percent of the chemical energy stored in the fuel is converted in to mechanical energy for traction: the remaining part is dissipated as heat in the exhaust gases (30%) and in the cooling circuit (40%). So a great amount of thermal energy (tens of kW) is available on a car and its effective recovery can dramatically increase the efficiency of the system. Hybrid systems facilitate this task, since the produced electric energy can be stored in the battery pack. Thermoelectric generators (TEGs) offer the possibility to directly convert thermal energy into electricity with a reduced complexity and potential low cost. Even though available semiconducting junctions are characterized by low efficiency and limited operating temperatures, coupling a TEG to the internal combustion engine would allow recovering about 1 kW of electric power on a medium size car, with a reduction of CO2 emissions of about 10 g/km.

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Increasing the Energy Efficiency of an Internal Combustion Engine for Ship Propulsion with Bottom ORCs

Applied Sciences ◽

10.3390/app10196919 ◽

2020 ◽

Vol 10 (19) ◽

pp. 6919

Author(s):

Melchiorre Casisi ◽

Piero Pinamonti ◽

Mauro Reini

Keyword(s):

Internal Combustion Engine ◽

Energy Recovery ◽

Combustion Engine ◽

Cooling Water ◽

Organic Rankine Cycle ◽

Rankine Cycle ◽

Internal Combustion ◽

Ship Propulsion ◽

Payback Time ◽

Temperature Levels

The study examines the option of adding a bottom Organic Rankine Cycle (ORC) for energy recovery from an internal combustion engine (ICE) for ship propulsion. In fact, energy recovery from the exhaust gas normally rejected to the atmosphere and eventually from the cooling water circuit (usually rejected to the sea) can significantly reduce the fuel consumption of a naval ICE during its operation. In the paper, different possible bottom ORC configurations are considered and simulated using the Aspen® code. Different working fluids are taken into account, jointly with regenerative and two-temperature levels designs. The energy recovery allowed by each solution is evaluated for different engine load, allowing the identification of the most suitable ORC configuration. For the selected case, the preliminary design of the main heat exchangers is carried out and the off-design performance of the whole combined propulsion plant (ICE + ORC) is evaluated, leading to a preliminary analysis of cost saving during normal ship operation. The results of this analysis show an increase in power output of about 10% and an expected Payback Time of less than 6 years.

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Time-Optimal Low-Level Control and Gearshift Strategies for the Formula 1 Hybrid Electric Powertrain

Energies ◽

10.3390/en14010171 ◽

2020 ◽

Vol 14 (1) ◽

pp. 171

Author(s):

Camillo Balerna ◽

Marc-Philippe Neumann ◽

Nicolò Robuschi ◽

Pol Duhr ◽

Alberto Cerofolini ◽

...

Keyword(s):

Internal Combustion Engine ◽

Energy Recovery ◽

Combustion Engine ◽

Internal Combustion ◽

Engine Operation ◽

Energy Recovery System ◽

Low Level ◽

Recovery System ◽

Time Optimal ◽

Hybrid Electric

Today, Formula 1 race cars are equipped with complex hybrid electric powertrains that display significant cross-couplings between the internal combustion engine and the electrical energy recovery system. Given that a large number of these phenomena are strongly engine-speed dependent, not only the energy management but also the gearshift strategy significantly influence the achievable lap time for a given fuel and battery budget. Therefore, in this paper we propose a detailed low-level mathematical model of the Formula 1 powertrain suited for numerical optimization, and solve the time-optimal control problem in a computationally efficient way. First, we describe the powertrain dynamics by means of first principle modeling approaches and neural network techniques, with a strong focus on the low-level actuation of the internal combustion engine and its coupling with the energy recovery system. Next, we relax the integer decision variable related to the gearbox by applying outer convexification and solve the resulting optimization problem. Our results show that the energy consumption budgets not only influence the fuel mass flow and electric boosting operation, but also the gearshift strategy and the low-level engine operation, e.g., the intake manifold pressure evolution, the air-to-fuel ratio or the turbine waste-gate position.

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