Proceedings of the
5th International Seminar on
ORC Power Systems
9 - 11 September 2019, Athens Greece
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Characterization of Organic Rankine Cycle System for Waste Heat Recovery from Heavy Duty Engine Coolant and Exhaust


Go-down orc2019 Tracking Number 159

Presentation:
Session: Session 4C: Waste heat (2)
Room: Templar's
Session start: 14:00 Tue 10 Sep 2019

Sandhya Thantla   sandhyat@kth.se
Affifliation: KTH Royal Institute of Technology

Jonas Aspfors   jonas.aspfors@scania.com
Affifliation: Scania CV AB

Jens Fridh   jens.fridh@energy.kth.se
Affifliation: KTH Royal Institute of Technology

Anders Christiansen Erlandsson   ace@itm.kth.se
Affifliation: KTH Royal Institute of Technology


Topics: - System Design and Optimization (Topics), - Volumetric expanders (Topics), - Simulation and Design Tools (Topics), - Waste heat recovery (Topics), - Oral Presentation (Preferred Presentation type)

Abstract:

To meet the strict legislations on the carbon-dioxide emissions, Organic Rankine Cycle (ORC) Waste Heat Recovery (WHR) technology is being extensively studied and applied in long haulage Heavy-Duty (HD) truck engines. It is necessary to maximize heat recovery from the HD engines to achieve the objective of reducing fuel consumption and improving efficiency. Volumetric expanders are being considered to be reliable technologies for ORC WHR systems in HD commercial vehicles. The focus of this paper is to characterize the ORC WHR system of a HD truck engine encompassing a volumetric expander, for the boundary conditions imposed by the engine coolant and the exhaust gas of the HD engine. Based on the quality of heat rejected from the engine at some chosen engine operating points, a study on changing the volume ratio and displacement volume of the expander is presented in this paper. Different WHR configurations integrated with the engine exhaust, engine coolant or both the exhaust and coolant as the heat sources are studied using the 1D simulation tool GT-suite. A Scroll-type volumetric expander is represented in the 1D model through maps of expander effectiveness and volumetric efficiency derived from a semi-empirical model of the expander. The main objective of this work is to achieve overall system efficiency using different configurations of the engine and WHR system, and expander sizing. By investigating with unconventional engine coolant temperatures as the heat source for WHR, an optimum engine coolant temperature is proposed based on the overall system performance when using the Scroll expander with R245fa as the working fluid. The optimum expander size and the number of expanders required for improved system efficiency is also determined and compared based on the subjected boundary conditions.