Technical solutions for increasing the energy perfo r- [626954]

Technical solutions for increasing the energy perfo r-
mance of internal combustion engines
Rareș -Lucian Chiriac1, Anghel Chiru2, Ovidiu Andrei Condrea3 and Radu George
Togănel4
1 Transilvania University of Brașov, B -dul Eroilor nr.29, 500036 Brașov, Rom ânia
2 Transilvania University of Brașov, B -dul Eroilor nr.29, 500036 Brașov, România
3 Transilvania University of Brașov, B -dul Eroilor nr.29, 500036 Brașov, România
4 Transilvania University of Brașov, B -dul Eroilor nr.29, 500036 Brașov, România
Abstract. Internal combustion engines have an efficiency of operating which
can be exploit to increase its performance. Part of the residual gases can be r e-
covered through the technical solutions such as turbocharging. The turbochar g-
ing solution is one of the most pop ular technical solutions for increasing the e n-
ergy performance of internal combustion engines. For the turbocharging pr o-
cess it is used a turbocharger. The turbocharger can contribute also with new
technical solutions to increase the energy performance of the internal combu s-
tion engines. One of the solutions proposed for the theoretical and experimental
research is the hybrid turbocharger , which has a double function, namely to
compress the fresh air for the internal combustion engine, and to generate ele c-
tric energy for the electric engine of the vehicle both for consumption and for to
be stored in batteries. This article aims is to present new to solutions for i n-
creasing the energy performance of internal combustion engines and to demo n-
strate the efficienc y of the new solutions such as a hybrid turbocharger through
calculations and simulation using the AMESim software.
Keywords: internal combustion engines , hybrid turbocharger , electric energy .
1 Introduction
More energy efficiency and less polluting processes are required in the internal co m-
bustion engines sector. The compression -ignition engines are used in generating ele c-
tricity, marine and transportation and the the Otto engine for transportation use but in
both cases the proces ses can be improved and made enable to higher pressure ratios
and also to generate electricity in sufficient operating conditions. [1]
Regarding the energy heat balance values from Otto and Diesel engine calculated on a
average amount which shows that the internal combustion engines can be improved
through new constructive solutions specifically for turbocharged engines. [2] The
turbocharger is positioned on the ex haust gases pipe from the engine. [3] Therefore
the tu rbocharger can be adapt to a generator and to develop dual purposes, such as, for
example, the take -off of exhaust gas from the engine and to compress air and also
power green energy generation for the battery use and storege and consumers of the
vehic le. [4]

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2 Objective
The general objective of t he new hybrid turbocharger is to improve the energy co n-
sumption and to sustain the electrical intake of the vehicle. The technical objective of
this paper would be to simulate and validate the new turbo compound systems in a u-
tomotive industry for internal combustion engine.
To develop the AMESim simulation of the prototype model hybrid turbocharger it
muss be used more phases of simulation design. For instance the first system is the
compressor – alternator simulation (see Fig. 1.) .
As a secondary objective it will be described the component parts of the simulated
system and the presented the results and main equation of the software.

Fig. 1. Compressor -alternator system simulate with AMESim Sofware

The second level of simulation is the compressor -alternator system composed from
turbocharger as a rotary drive part coupled at a alternator as electrical generator and
the cosummers that are coupled thrue the battery. This is the main principal of the
prototype (see Fig. 2.).

Fig. 2. Compressor -alternator system simulate with AMESim Software

The third stage of the applicable solution on the engine is the hybrid turbocharger
coupled with a 4 cylinder engine simulate with AMESim Software. It can be seen the
turbocharger as a rotary drive part coupled at a alternator. The alternator has the fun c-
tion of a electrical generator and the cosummers that are coupled thrue the battery.
Also the hole system is bound to a engine. (see Fig. 3.)

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Fig. 3. Hybrid turbocharger coupled with a 4 cylinder engine simulate with AMESim Soft-
ware
3 Methodology
The basics equations used for the mathematical simulation of the compressor,
turbine and alternator expressed in terms of reduced or corrected variables are:

3.1. Compresor equasion

Speed

Mass flow rate

(1)
Where:
• T_st and P_ st are the standard pressure and temperature. [K]/ [kPa]
• T_up and P_up are the upstream temperature and pressure, [K]/ [kPa]

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3.2. Turbin equasion

Speed

Mass flow rate

(2)
Where:
• T_st and P_ st are the standard pressure and temperature , [K]/ [kPa]
• T_up and P_up are the upstream temperature and pressure, [K]/ [kPa]

3.3. Alternator equations

The main alternator parameter are rotary velocity in [rev/min], temperature in
[degC], current in [A], torque in [Nm], efficiency in [null] (i.e. no unit), losses in
[W] ( see Fig. 4.)

rotary velocity in [rev/min]
temperature in [degC]
current in [A]
torque in [Nm]
efficiency in [null] (i.e. no unit)
losses in [W]
Fig. 4. Alternator symbol and main parameters in AMESim Software

The main alternator equations with which the software AMESim calculate are
based on three categories like: computation with torque data, computation with
efficiency data and computation with losses data. ( see Tabel 1 ) [5]

Tabel 1. Main alternator equations
Computation with
torque data Computation with eff i-
ciency data Computation with losses
data
The electrical power is
computed with:
The electrical power is
computed with:
The electrical power is
computed with:

The maximum torque
datafile or ex pression
TmaxFile is evaluated:

, The efficiency datafile or
expression EffFile is
evaluated: e
, The maximum losses
datafile or expression
LmaxFile is evaluated:

,
The electromagnetic
torque is then computed The mechanical power is
then computed with: The thermal losses are
then computed with:

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with:
T P P
e d
The mechanical power
is:
P r t
The electromagnetic
torque is given by:

The mechanical power is
then computed with:
P P dh
The efficiency is given
by: e

Finally, the thermal
losses are: dh P P The electromagnetic
torque is given by:

Finally, the thermal
losses are: dh P P Finally, the efficiency is:
e

4 Results
The simulation had use a ro tation of the alternator shaft at 5000 revolutions per
minute and t he results of the simulation for all the three case are:
Tabel 2. Simulation results of the hybrid turbocharger
Title Value Unit
Current at port 4 5.00511 A
Output voltage 10.159 V
Output current 5.00511 A
Alternator efficiency 0.915363 null
Integral of error in PI 38.1677 V*s
Electrical power 50.8471 W
Mechanical power 55.5485 W

In the diagram it is represeted the values from Tabel 2. (see Fig. 5.)

Fig. 5. Diagram with results values
5 Conclusions
The new turbo compound systems in automotive industry for internal combustion
engine to recover energy has three basic elements : the extended shaft to accommodate

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the electrical energy generator at the blower end, a gear that reduce the rotation of the
turbocharger and a cooling system for the generator witch is optional .
The main advantages of the new hybrid turbocharger are: consume the green electr i-
cal energy and s torage in t he main battery of the vehicle, also r edirect to peripheral
computer consumers and to compress air for the engine.
Other studies will be presented. [ 6], [7]
6 References
1. Heim K., Existing and future demands on the turbocharging of modern large two -stroke
diesel engines. In: 8th Supercharging conference, 1 –2 October 2002, Dresden, Germany.
Author, F., Author, S.: Title of a proceedings paper. In: Editor, F., Editor, S. (eds.)
CONFERENCE 2016, LNCS, vol. 9999, pp. 1–13. Springer, Heidelberg (2016).
2. Payri, F., Improvement and application of a methodology to perform the Global Energy
Balance in internal combustion engines. Part 1: Global Energy Balance tool development
and calibration, Journal of Energy, vol. 152, 2018
3. Ponti F., Ravaioli V., De Cesare Estimation Methodology for Automotive Turbochargers
Speed Fluctuations due to Pulsating Flows , J. Eng. Gas Turbines Power, p. 137, 2014
4. Chiriac, R., New turbo compound systems in automotive industry for internal combustion
engine to recover energy, CAR2017 International Congress of Automotive and Transport
Engineering – Mobility Engineering and Environment, 8 –10 November 2017, Pitesti, R o-
mania, vol 252, 2017
5. LMS AMESim , Ameshelp Library, https://www.siemens.com/plm/support
6. Perrot, N., Experimental Study of Centrifugal Compressor Speed Lines Extrapolation for
Automotive Turbochargers, 2017, SAE Paper
7. Chiriac, R., New constructive solutions for hybrid turbochargers – as electrical energy ge n-
erator for increasing the green supply of the vehicule, International Conference for Docto r-
al Students 2017 (Brasov: “Transilvania” University)

7 Acknowledgments
I would like to thank for the cooperation to the company Garrett – turbocharger pr o-
ducers, Compa ny Siemens and “Transilvania” University of Brasov for support and
interest.