This document discusses the organic Rankine cycle (ORC) for recovering exhaust waste heat from a diesel engine. The ORC converts thermal energy from the engine exhaust into mechanical energy through evaporation and condensation of an organic working fluid. It works similarly to a traditional steam cycle but uses organic fluids instead of water. The document covers the working principle, construction, common working fluids, effects of various parameters, and advantages of the ORC system for waste heat recovery from diesel engines.

1. ORGANIC RANKINE CYCLE
FOR EXHAUST WASTE HEAT
RECOVERY OF A DIESEL
ENGINE
GUIDED BY PRESENTED BY
SREEVATSAN RAMESH VIPIN MP
( AP, ME) ROLLNO:52
S7,ME
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2. CONTENTS
• INTRODUCTION
• WORKING PRINCIPLE
• CONSTRUCTION OF ORC
• WORKING FLUIDS
• PERFORMANCE MAP OF THE DIESEL ENGINE
• ADVANTAGES OF ORC.
• EFFECT OF EVAPORATION PRESSURE.
• EFFECTS OF EXHAUST TEMPERATURE .
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3. INTRODUCTION
• Organic Rankine cycle(ORC) is a thermodynamic cycle which
convert thermal energy into mechanical.
• ORC technology is similar to a traditional steam turbine.
• ORC generators are a way to convert waste heat into
electricity.
• Internal combustion(IC) engines only convert about 40% of
the total fuel combustion energy into useful work.
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4. WORKING PRINCIPLE
• The ORC is a thermodynamic cycle that converts heat into work.
Figure 1: ORC
VIDEO
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5. CONSTRUCTION OF ORC
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Figure-2 Schematic diagram of the ORC system

6. T-S diagram of the ORC system
🌕 Process 1-2 (Expander)
🌕 Process 2-4 (Condenser)
🌕 Process 4-5 (Pump)
🌕 Process 5-1 (Evaporator)
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Figure-5

7. WORKING FLUIDS
• Water is the only working fluid for steam rankine cycle.
• Plenty of organic fluids are suitable for ORC.
WATER ORGANIC FLUIDS
Small, fast moving molecules Large flow rate
Metal parts and blade erosion No wear of blades and
metal parts
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8. CHOICE OF WORKING FLUID
• The selection of the working fluid is very important in ORC.
• In order to recover low-grade heat, the fluid generally has a
lower boiling temperature than water.
• Refrigerants and hydrocarbons are two commonly used
working fluids.
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9. PROPERTIES OF WORKING FLUIDS
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Figure-3 T-s diagram of the six selected working fluids
Table 1 Properties of the selected working fluids

10. EFFECT OF CRITICAL TEMPERATURE OF
WORKING FLUIDS
• Net power output increases with increasing working fluids
critical temperature
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Figure-4

11. EFFECT OF EVAPORATION PRESSURE
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• Power output increases with the evaporation pressure
Figure-6

12. PERFORMANCE MAP OF THE DIESEL ENGINE
• Exhaust energy of diesel engine varies with the operating
conditions.
• Variation of the exhaust energy has an effect on the operating
parameters of the ORC system.
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(a) (b)

13. EFFECT OF EXHAUST TEMPERATURE
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Figure-7

14. INSTALLATION COST
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The ORC system will cost an
estimated 2000-2500$/kW of
installed capacity

15. ADVANTAGES OF ORC
• High turbine / thermodynamic cycle efficiency.
• Turbine low mechanical stress.
• No need to demineralize water.
• No risk of blade erosion.
• Non-oxidizing working fluid with no corrosion issues.
• Completely automatic .
• Simple maintenance procedure.
• No operator attendance required.
• Long life of the plant (> 20 years);.
• Possibility to work at low temperatures (90+°C)
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16. CONCLUSION
• ORC system is used to recover the exhaust waste heat from a
diesel engine.
• Thermal efficiency and exergy efficiency are relative low.
• Power output increases with the evaporation pressure.
• Net power output increases with increasing working fluids
critical temperature
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17. REFERENCES
Fubin Yang, Hongguang Zhang, Songsong Song,Chen Bei, Hongjin
Wang,Enhua Wang “Thermoeconomic multi-objective optimization of an
organic Rankine cycle for exhaust waste heat recovery of a diesel engine”.
Energy 93(2015) 2208-2228.
Wolfgang Lang, Piero Colonna, Raimund Almbauer “Assessment of Waste
Heat Recovery From a Heavy-Duty Truck Engine by Means of an ORC
Turbogenerator”. Institute for Internal Combustion Engines and
Thermodynamics, Graz University of Technology , inffeldgasse 21 ,
Graz,8010,Austria, APRIL2013,Vol,135/042313-1
Rongqi Shi, Tianqi He, Jie Peng, Yangjun Zhang, Weilin Zhuge “System
design and control for waste heat recovery of automotive engines based on
Organic Rankine Cycle ”State Key Laboratory of Automotive Safety and
Energy, Tsinghua University, Beijing, China 0360-5442/©(2016) Elsevier Ltd
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