Recovery and effective utilization of waste heat from the exhaust of internal combustion engines for cooling applications using ANSYS

2021 ◽  
pp. 095440622110568
Author(s):  
Ghulam Abbas Gohar ◽  
Muhammad Zia Ullah Khan ◽  
Hassan Raza ◽  
Arslan Ahmad ◽  
Yasir Raza ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Heat Recovery ◽  
Waste Heat ◽  
Internal Combustion ◽  
Heat Energy ◽  
Exit Velocity ◽  
Inlet Velocity ◽  
Exhaust Gases ◽  
Recovery Unit ◽  
Libr Solution

The exhaust gases from an internal combustion (IC) engine carry away about 75% of the heat energy which means only 25% of heat energy is operated for power production. A recovery unit at the exhaust outlet port can ensure heat exchange between different temperature fluids through conjugate heat transfer phenomena. This study represents heat recovery from exhaust gases that are emitted from IC engines which can be utilized in various applications such as vapor absorption refrigeration systems. In the present work, a new type of perforated fin heat exchanger for waste heat recovery of exhaust gases is designed using SolidWorks, and the flow field design of the heat recovery system is optimized using ANSYS software. Various parameters (velocity, pressure, temperature, and heat conduction) of hot and cold fluid have been analyzed. Inlet velocity of cold fluids including refrigerant (LiBr solution), water, and graphene oxide (GO) nanofluid have been adopted at 0.03 m/s, 0.165 m/s, and 0.3 m/s, respectively. Inlet velocity of hot fluid is taken as 2 m/s, 4 m/s, and 6 m/s, respectively, to develop a test matrix. The results showed that maximum temperature reduction by the exhaust is achieved at 104.8°C using graphene oxide nanofluids with an inlet velocity of 0.3 m/s and exit velocity of 2 m/s in the heat recovery unit. Similarly, temperature reduction by exhaust gases is acquired at 102 °C using water and 96.34 °C by using a refrigerant (LiBr solution) with the same exit velocity (2 m/ s). Furthermore, maximum effectiveness of 0.489 is also obtained for GO nanofluid when compared with water and the refrigerant. On the other hand, the refrigerant has the maximum log mean temperature difference from all fluids with a value of 224.4 followed by water and GO.

scholarly journals Cuk Converter for Waste Heat Recovery from Automobile Engine using Thermoelectric Generator with Air as Coolant

2020 ◽  
Vol 9 (4) ◽  
pp. 249-252
Keyword(s):  
Energy Efficiency ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Thermoelectric Generator ◽  
Waste Heat ◽  
Combustion Engine ◽  
Electrical Energy ◽  
Internal Combustion ◽  
Heat Energy ◽  
Maximum Power

The growing concern on energy conservation and reduction of carbon footprint has led to a lot of inventions and innovations in terms of energy-efficient technologies in all the energy consuming applications. The automobile sector is a crucial zone where these technologies have a major role to play due to the sheer abundance of the number of automobiles.Many small refinements, alterations and innovations are happening in this field which has led to furthermore energy economic automobiles than before.But even in an advanced internal combustion engine, about two-thirds of fuel consumed by an automobile is discharged into the surroundings as waste heat. The effect of this is the increase in the surrounding air temperature which in turn contributes significantly to global warming. This paper proposes amethod to reduce the emission of heat from automobiles by designing and implementinga waste heat recovery system for internal combustion (IC) engines. The key aim is to reduce the amount of heat released into the environment and to convert it into useful energy. A thermoelectric generator (TEG) assembly is used to directly convert the wasted heat energy from the automobile into electrical energy. This electrical energy is conditioned using a Cukconverter and maximum power point tracking (MPPT) algorithm is embedded in the converter for impedance matching and maximum power transfer from TEG to the converter. The conditioned output is used to charge the battery of the vehicle. This methodologyalso increases the energy efficiency of the vehicle as a higher capacity battery can be employed.The proposed system can work well under varying temperature conditions to give a constant output. It can be implemented in any mechanical/ electrical systems were there is wastage of heat energy like gas pipelines, wearable electronics, space probes, cookstoves, boilers, thermal vision, etc. One of the thrust areas where this technology can be effectively utilized in today’s world is in electric vehicles where the energy efficiency is the most important factor.

A Study of Waste-Heat Recovery Unit for Power Transformer

2014 ◽  
Vol 875-877 ◽  
pp. 1661-1665 ◽  
Author(s):  
Zi Jie Chien ◽  
Hung Pin Cho ◽  
Ching Song Jwo ◽  
Sih Li Chen ◽  
Yi Lun Lin
Keyword(s):  
Power Supply ◽  
Heat Recovery ◽  
Waste Heat ◽  
Power Transformer ◽  
Heat Energy ◽  
Hot Water ◽  
Iron Core ◽  
Water Recovery ◽  
Recovery Unit ◽  
Save Energy

This study discussed the feasibility of developing a system to circulate the heat loss from the coil and iron core of the power transformer equipped for buildings during power supply to the heat recovery unit. This study affixed a copper tube into the transformer insulating oil, allowing the water to circulate at normal temperature in the coil tube, and absorb the heat energy generated by the transformer coil and iron core. The heat energy was then recovered and stored. A low tension power transformer (7.5 KV) was used in the experiment. The operation was carried out in transforming power supply mode to seek for the most suitable recovery unit for various occasions. The test results showed that if the hot water recovery efficiency is 50%, in the course of producing hot water, the mean temperature of 17.5 L normal temperature water can be increased from 20°C to 50°C, thus producing 12.5 kJ heat only spends about 34 min. The results proved that the recovery unit for the heat from the power transformer can benefit from heating, prolong the transformer's lifetime, increase the power supply efficiency, and reduce the air conditioning load to save energy and to reduce global warming.

Design of a heat recovery unit using exhaust gases for energy savings in an absorption air conditioning unit

2021 ◽  
pp. 117031
Author(s):  
Mostafa El-Shafie ◽  
M. Khalil Bassiouny ◽  
Shinji Kambara ◽  
Samy M. El-Behery ◽  
A.A. Hussien
Keyword(s):  
Air Conditioning ◽  
Heat Recovery ◽  
Energy Savings ◽  
Exhaust Gases ◽  
Recovery Unit

Analytical Investigation of a Thermal-Supercharged Internal Combustion Engine Compounded With Organic Rankine Cycle for Waste Heat Recovery

2017 ◽  
Author(s):  
Manuel Jiménez-Arreola ◽  
Fabio Dal Magro ◽  
Alessandro Romagnoli ◽  
Meng Soon Chiong ◽  
Srithar Rajoo ◽  
...  
Keyword(s):  
Internal Combustion Engine ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Combustion Engine ◽  
Rankine Cycle ◽  
Internal Combustion ◽  
Analytical Investigation ◽  
Back Pressure ◽  
Recovery Method

Waste heat recovery is seen as one of the key enablers in achieving powertrain of high efficiency. The exhaust waste heat from an internal combustion engine (ICE) is known to be nearly equivalent to its brake power. Any energy recovered from the waste heat, which otherwise would be discarded, may directly enhance the overall thermal efficiency of a powertrain. Rankine cycle (indirect-recovery method) has been a favorable mean of waste heat recovery due to its rather high power density yet imposing significantly lesser back pressure to the engine compared to a direct-recovery method. This paper presents the analytical investigation of a thermal-supercharged ICE compounded with Rankine cycle. This system removes the turbocharger turbine to further mitigate the exhaust back pressure to the engine, and the turbocharger compressor is powered by the waste heat recovered from the exhaust stream. Extra caution has been taken when exchanging the in/output parameters between the engine and Rankine cycle model to have a more realistic predictions. Such configuration improves the engine BSFC performance by 2.4–3.9%. Water, Benzene and R245fa are found to be equally good choice of working fluid for the Rankine cycle, and can further advance the BSFC performance by 4.0–4.8% despite running at minimum pressure setting. The off-design analyses suggested the operating pressure of Rankine cycle and its expander efficiency have the largest influence to the gross system performance.

Exergy Analysis of Natural Gas ICE-Based CHP System

2009 ◽  
Author(s):  
Xiling Zhao ◽  
Lin Fu ◽  
Shigang Zhang ◽  
Jianzhang Zhu ◽  
Baomin Huang ◽  
...  
Keyword(s):  
Natural Gas ◽  
Heat Recovery ◽  
Waste Heat ◽  
Operation Mode ◽  
Mode I ◽  
Mode Ii ◽  
Exhaust Gas ◽  
Liquid Desiccant ◽  
Water Flows ◽  
Recovery Unit

A challenge for CHP (Combined heating and power) system is the efficient integration of distributed generation (DG) equipment with thermally-activated (TA) technologies. Tsinghua University focuses on laboratory and demonstration research to study the critical issues of CHP systems, advance the technology and accelerate its application. The Research performed at the Building Energy Research Center (BERC) Laboratory focuses on assessing the operational performance and efficiency of the integration of current DG and TA technologies. The test system is composed of a 70-kW natural gas-fired internal combustion engine (ICE) with various heat recovery units, such as a flue gas-to-water heat recovery unit (FWRU), a jacket water heat recovery unit (JRU), liquid desiccant dehumidification systems (LDS), an exhaust-gas-driven double-effect absorption heat pump (EDAHP), and a condensation heat recovery unit (CRU)). In the winter, the exhaust gas from the ICE is used in the FWRU (operation mode I) or used to drive the EDAHP directly, and the exhaust gas from the EDAHP is used in the CRU (operation mode II). The water flows from the CRU can be directed to the evaporator side of the EDAHP as the lower-grade heat source. The water flows from the condensation side of the EDAHP, in conjunction with the jacket water flows from the JRU, is used for heating. In summer, the exhaust gas from the ICE is used to drive the EDAHP for cooling directly, and the waste heat of the jacket water is used to drive the liquid desiccant dehumidification systems, to realize the separate control of heat and humidity. In this paper, the exergy and energy analysis has been done on operation mode I and II according to the actual testing results, and it is show that the exergy efficiency of operation mode II is improved by 1.5% than operation mode I, and the energy efficiency of operation mode II is improved by 11% than operation mode I. The only way to improve the whole CHP is to maximize the use of the heat recovered by the ICE and to utilize the remaining heat of exhaust gas in other waste-heat driven equipments capable of using low grade waste heat like the CRU.

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