Multi-objective optimization of turbo-ORC systems for waste heat recovery on passenger car engines

Kévin Rosset, Violette Mounier, Eliott Guenat and Jürg Schiffmann

Energy, 2018, vol. 159, issue C, 751-765

Abstract: Waste heat recovery from passenger car internal combustion engines by means of an organic Rankine cycle (ORC) system is promising for reducing CO2 emissions. In this study, different cycle configurations capable of converting waste heat from both coolant and exhaust gases are investigated based on different working fluid categories. Radial-inflow turbines are considered as expansion devices and corresponding isentropic efficiencies are evaluated based on a preliminary design map accounting for the effect of the pressure ratio. Mechanical losses resulting from the use of a gas-bearing-supported rotor driving a permanent magnet generator are also evaluated. In order to identify the turbo-ORC system design tradeoffs, constrained multi-variable and multi-objective optimizations are performed using an evolutionary algorithm. It is found that the optimal cycle configuration and working fluid depend on the available space in the vehicle and that the condenser is the most critical component for the ORC system integration. In addition, the most suitable working fluids for this application are characterized by (1) a boiling point close to the heat sink temperature, (2) a high critical pressure, and (3) a high molecular weight. The resulting optimal radial-inflow turbines are 10–33 mm in tip diameter and operate at 80–330 krpm.

Keywords: Internal combustion engine; Waste heat recovery; Organic Rankine cycle; Turbo-generator preliminary design; Heat exchanger sizing; Multi-objective optimization (search for similar items in EconPapers)
Date: 2018
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (5)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544218312581
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:159:y:2018:i:c:p:751-765

DOI: 10.1016/j.energy.2018.06.193

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().