Exhaust Waste Heat Conversion - Report Example

Literature Review Name Institution Name Date Introduction The rapid economic development across the world including the shortage of energy has offered opportunities of researching and studying methods to improve energy conversion and sustainability measures. Internal combustion engines are some of the components that exhaust heat and noise that can be converted into energy. Jadhao and Thombare (2013) estimates around 30-40% of heat supplied to the engine is utilized in mechanical work while the rest is released to the environment through mechanisms such as engine cooling systems and exhaust gases. These are wastages and utilizing the waste heat and noise can improve environment protection and efficiency of the processes. These wastes are common in other machines and components such as computer parts, factories and other facilities that utilizes energy. Technologies Used to Convert Exhaust Waste to Energy The human and environmental demands forces researchers and inventors to continue developing and creating products to accomplish specified requirements and demands. The conversion of waste heat and noise is becoming an integral component in the society and numerous innovations and improvement of current technologies gains traction. Some of the technologies used in converting heat and similar wastes include thermoelectric generators, Rankine cycle and turbocharger based technologies. Thermoelectric generators Saidur et al. (2012) states that the use of thermoelectric generators promote sustainable development, reduction in greenhouse gas emissions and enhancing energy efficiency. A normal TEG consist of p- and n- type semiconductor that are connected electrically in series and thermally in parallel. The amount of current depends on the difference in temperature between the two junctions and the material used (Hou et al. 2014). The arguments supporting such a design is the continuous output of power without instances of performance degradation. Continuous developments in TEG are common and researchers continues to propose alternative adjustments to improve the efficiency. Saidur et al. (2012) analyzed numerous research papers and concluded that some of the recent development of TEG that are applicable to the automotive industry include photovoltaic and thermoelectric systems, and maximum power point tracker. Saidur et al. (2012) presents how the TEG can be designed and used in collecting wastes and reutilizing the waste. The first step is use of heat exchanger that is mounted on the exhaust system, the thermal energy mechanism is used to generate electricity, and power converter is used to achieve the expected output or maximum power transfer (Zhang et al., 2014). However, some of the challenges associated with the process include low thermal efficiency, and the bigger size of the extended piping and radiator to the exhaust manifold. Rankine cycle Hossain and Bari (2014) utilized Rankine Cycle to improve efficiency of a 4o kW diesel engine generator. The research was premised on shell and tube heat exchanger through the use of water and two organic fluids: Ammonia and HFC-134a. Hossain and Bari (2014) found out the use of heat exchanger can improve the efficiency of the engine by 10% (water), 9% (Ammonia) and 8% (HFC-134a). Without going into the specifics of the processes, it is evident that the use of Rankine Cycle can improve the efficiency and performance of any engine. The following image summaries the Rankine cycle: Source (Kapooria, Kumar and Kasana, 2008) Wang et al. (2013) proposes a thermal efficient model that incorporates the design of organic Rankine cycle in improving efficiency and performance in the optimal operation condition and thermal efficacy. Based on the model, Wang et al. (2013) states that the performance of organic Rankine cycle depends on the working fluid, since the fluid should have high vaporization latent, low specific liquid heat and low critical temperature (Ayodele and Kahn, 2014). These assertions indicates the importance of Rankine cycle in recovering waste noise and heat in improvement of engine and other energy sources efficiency. Six stroke IC engine and Turbocharger Technology Saidur et al. (2012) discusses a six-stroke form of an engine that combines the basic four stroke engine with additional two cycles to reduce emissions while producing higher efficiency. Saidur et al. (2012) states some researchers such as Hayasaki et al. proposes a model that incorporates a second compression systems are opposed to the traditional four-stroke diesel system. A normal four stroke cycles has four components, which are the exhaust stroke, combustion stroke, compression stroke and intake stroke. The argument is the exhaust from the four strokes are captured and processed through the additional two strokes (Markides, 2013). The design also enable strapping of exhaust through inclusion of water and the process involves expansion activities that improves the efficiency and performance activities. The effectiveness can be improved further through valve closing timing and modification of the engine in an ideal thermodynamics model. A naturally aspirated engine produces large amounts of waste heat and can be recovered through the use of turbocharger. The effectiveness of a turbocharger depends on the supercharger that employs an exhaust system design (Wang et al. 2011). The ideology behind the turbocharger is using the pressure and heat occurring in the expanding exhaust gas to improve the efficiency of the engine power. The components that make up a turbocharger includes center housing and rotating assembly, actuator, waste gate valve, compressor, shaft and turbine (Liu et al., 2015). The design increases power density and engine downsizing resulting in increase in engine efficiency. Even though turbocharger is an effective approach in recovering energy from heat waste, Saidur et al. (2012) highlights numerous challenges. The challenges in the automotive industry include turbo lag (i.e. transient response and hesitation) during low accelerations and consequences of heated bearings. The turbo large inhibits the performance and drivability of the engine. The problems associated with the turbo lag are associated with the numerous equipment in the design process and reduction in useful turbine energy. The proposed solution to the problem is use of 2-stage turbocharger to address the challenges (Wang et al. 2013). The change of the design results in minimization of the turbo lag, improved dynamic performance, better low end torque, low pressure stage efficiencies and higher power outputs. It illustrates that the turbocharger is an effective strategy, which may be employed in addressing heat wastes from automotive engines. The following image shows the components that forms turbo technology: Source (MTU 2016) The Benefit of Converting Exhaust Waste Heat and Noise Apart from the demand for the society and environment, converting exhaust waste into forms of energy has numerous benefits. Some of the benefits include enhancement of energy efficiency, reduction of greenhouse emissions and other forms of pollution, and other numerous benefits. Enhance energy efficiency Jadhao and Thombare (2013) highlights numerous benefits of recovery of waste heat and noise and specifies the importance of combustion process efficiency. Jadhao and Thombare (2013) associate the efficiency to reduction in process cost and utility costs. For example, improved use of energy translates to reduced amounts of energy required to complete a given task. For instance, a single kilowatts can be used to do more than one thing compared with the current situations in which more energy is required to complete a single task. This is achieved through recycling the wastes whether in terms of heat or noise, and used to do similar tasks or alternative tasks. The example of turbocharger is a good example in which the recycling process improves efficient through improving the burning process. The design and improvement of the processes contributes to energy efficiency (Weng and Huang, 2013). Manufacturers and designers will be required to continue innovating and creativity, which will be reflected in the new designs and products (Wang et al. 2013). The designs relies on the technological advancement meaning the target is efficiency since the consumers would have understood the threats of the current processes and the benefits of alternative process. For example, turbocharged vehicles use about the similar amounts of energy but produces additional torque, which increases the speed and power of the car (Weng and Huang, 2013). Making such adjustments on other products improves the entire efficiency of the entire production and development processes (Wang et al. 2013). Reduction of greenhouse gas emissions and pollution Environmental degradation is a major issue associated with the current processes and activities in utilization of fossil fuels and other non-renewable energy, which is commonly used in different devices. Jadhao and Thombare (2013) presents examples of toxic combustible wastes include particulate matter, nitrogen oxides, hydrocarbons and carbon monoxide, which are released into the atmosphere. The recovery of the heat and noise reduces the amount of wastes resulting in reduction of environmental pollution. Saidur et al. (2012) also highlights the consequences of lack of effective energy management strategies for preventing environmental pollution. The problems associated with the release of the gases are greenhouse gases, and improvement of systems and processes can reduce pollution of the environment (Saidur et al. 2012). Hence, the technological advancement is waste recycling is among the strategies to address and support environmental sustainability. The following chart illustrates the common greenhouse gases in percentage form: Source: US Environmental Protection Agency (2016) Promote sustainable development Tchanche et al. (2011) highlight the role and the urge of different stakeholders in advancing sustainable development through efficiency in utilisation of energy. Numerous processes exists that can advance sustainable development, and Tchanche et al. (2011) present the role of the government, which continues to formulate and implement legislative targeting sustainable measures. These legislative encourages researchers and scientists employ processes such as the Rankine cycle to create products and services that integrates the sustainable development requirements (Weng and Huang, 2013). Saidur et al. (2012) states the world is changing and the demands for energy are increasing and emission of greenhouse gases raises more problems. Promoting sustainable development provides awareness of continuous research and development, and seeking for alternative mechanisms of energy utilization and associated efficiencies. Saidur et al. (2012) presents examples of six stroke cycle IC engine, organic Rankine cycle and thermoelectric generators as example of measures to promote sustainable development. The current problems of energy sources especially from fossil fuels creates numerous problems including increasing the cost of production and development. Wang et al. (2013) states that the sustainable development requires sustainable source of energy. The fossil fuel is not sustainable meaning that employing conversion mechanisms can improve the sustainability requirements. Other benefits Jadhao and Thombare (2013) states that reduction in equipment sizes is associated with recovering waste noise and heat. Jadhao and Thombare (2013) argues that the recovery reduces the consumption of fuel translating in reduction of flue gas produced. These numerous processes translates to overall reduction in equipment sizes. The equipment sizes reduction translates to other benefits associated with reduction in auxiliary energy consumption. Efficient is an important component and Saidur et al. (2012) highlights other factors in the development and utilization of the technology especially on turbocharger. Some of the benefits of the turbocharger include high performance engines, economic value and fuel efficiency (Ovik et al., 2016). These processes can be reciprocated in other designs targeting efficient and other engine utilization mechanisms. Sources of Heat and Energy to be Converted to Substantial Electrical Power and Energy Engines are the common sources of heat and noise wastes and Jadhao and Thombare (2013) present numerous devices and engines that produces heat and noise wastes. These engines include trucks and road engines, marine applications, earth moving machineries, water air cooled engine, construction machines and small agriculture tractors, and small air cooled diesel engine (Ovik et al., 2016). Hossain and Bari (2014) supports the argument of engines because the authors state that exhaust gas is the common component of diesel engine. Tchanche et al. (2011) discusses numerous sources of heat and noise, which can be integrated into an organic Rankine Cycle to produce energy efficiency. The authors’ state hydrocarbons and refrigerants that are organic in nature can be utilized rather than water. Tchanche et al. (2011) highlights some of the sources of wastes include industrial processes and thermal devices. The authors present an important component in which legislative conditions and frameworks continues to advocate towards sustainable measures. Numerous others sources of heat release exist and can be used to improve products efficiency. For example, the computer systems and other technological components requires energy to function effectively (Jadhao and Thombare, 2013). For instance, laptops and printing machines have capacitors and other electrical fixtures, which are used to store some energy or ensure the effectiveness of the machines components located on the motherboard (Zhang et al. 2014). Some of the energy is lost during the heating process and use of the machines, and improving the efficient through processes similar to turbocharger system or other storage mechanisms (Popli, Rodgers and Eveloy, 2012). Mobile phones, energy produced through pressing the keys of different technological products such as automated machines also produces some forms of heat. Improving the efficient of the systems through recycling the heat and noise produced would improve general use of the system. Conclusion/Summary From the discussions, it is evident there are large potentials of energy saving through recovering energy from waste heat and noise. Waste heat recovery process involves capturing and reusing the waste heat that is obtained through numerous engines and energy sources including solar and other electrical wastes. If these technologies are adopted by the automotive industry, efficiency and performance can be improved by addressing the sources of emissions, and changing these requirements to benefit the technological requirements. Numerous technologies exist that can be used to reuse the heat released by the wastes. Some of these technologies include thermoelectric generators, Rankine cycle and six stroke IC engine and Turbocharger Technology. In utilizing these technologies, some of the benefits includes environment protection, development sustainability among other measures. The sources of reused heat include computers processors and components, industrial facilities, and automotive industry. Exhaust waste heat conversion is important because it improves the efficiency and productivity of energy with general economic benefits to an individual and society. References Ayodele, O.L. and Kahn, M.T.E., 2014, August. Underutilise waste heat as potential to generate environmental friendly energy. In 2014 International Conference on the Eleventh industrial and Commercial Use of Energy (pp. 1-6). IEEE. Hossain, S.N. and Bari, S., 2014. Waste heat recovery from exhaust of a diesel generator set using organic fluids. Procedia Engineering, 90, pp. 439-444. Hou, G., Bi, S., Lin, M., Zhang, J. and Xu, J., 2014. Minimum variance control of organic Rankine cycle based waste heat recovery. Energy Conversion and Management, 86, pp.576-586. Jadhao, J.S. and Thombare, D.G., 2013. Review on exhaust gas heat recovery for IC engine. International Journal of Engineering and Innovative Technology (IJEIT), 2(12) 93-100. Liu, X., Deng, Y.D., Li, Z. and Su, C.Q., 2015. Performance analysis of a waste heat recovery thermoelectric generation system for automotive application. Energy Conversion and Management, 90, pp. 121-127. Markides, C.N., 2013. The role of pumped and waste heat technologies in a high-efficiency sustainable energy future for the UK. Applied Thermal Engineering, 53(2), pp. 197-209. Ovik, R., Long, B.D., Barma, M.C., Riaz, M., Sabri, M.F.M., Said, S.M. and Saidur, R., 2016. A review on nanostructures of high-temperature thermoelectric materials for waste heat recovery. Renewable and Sustainable Energy Reviews, 64, pp. 635-659. Popli, S., Rodgers, P. and Eveloy, V., 2012. Trigeneration scheme for energy efficiency enhancement in a natural gas processing plant through turbine exhaust gas waste heat utilization. Applied Energy, 93, pp. 624-636. Saidur, R., Rezaei, M., Muzammil, W.K., Hassan, M.H., Paria, S. and Hasanuzzaman, M., 2012. Technologies to recover exhaust heat from internal combustion engines. Renewable and Sustainable Energy Reviews, 16(8), pp. 5649-5659. Saidur, R., Rezaei, M., Muzammil, W.K., Hassan, M.H., Paria, S. and Hasanuzzaman, M., 2012. Technologies to recover exhaust heat from internal combustion engines. Renewable and Sustainable Energy Reviews, 16(8), pp. 5649-5659. Tchanche, B.F., Lambrinos, G., Frangoudakis, A. and Papadakis, G., 2011. Low-grade heat conversion into power using organic Rankine cycles–A review of various applications. Renewable and Sustainable Energy Reviews, 15(8), pp. 3963-3979. Wang, D., Ling, X., Peng, H., Liu, L. and Tao, L., 2013. Efficiency and optimal performance evaluation of organic Rankine cycle for low grade waste heat power generation. Energy, 50, pp. 343-352. Wang, T., Zhang, Y., Peng, Z. and Shu, G., 2011. A review of researches on thermal exhaust heat recovery with Rankine cycle. Renewable and Sustainable Energy Reviews, 15(6), pp. 2862-2871. Weng, C.C. and Huang, M.J., 2013. A simulation study of automotive waste heat recovery using a thermoelectric power generator. International Journal of Thermal Sciences, 71, pp.302-309. Zhang, Y.Q., Wu, Y.T., Xia, G.D., Ma, C.F., Ji, W.N., Liu, S.W., Yang, K. and Yang, F.B., 2014. Development and experimental study on organic Rankine cycle system with single-screw expander for waste heat recovery from exhaust of diesel engine. Energy, 77, pp. 499-508. Kapooria, R.K., Kumar, S. and Kasana, K.S., 2008. An analysis of a thermal power plant working on a Rankine cycle: A theoretical investigation. Journal of Energy in Southern Africa, 19(1), pp.77-83. MTU. (2016). Turbocharging: Key technology for high-performance engines. Retrieved from http://www.mtu-online.com/fileadmin/fm-dam/mtu-global/technical-info/white-papers/3100641_MTU_General_WhitePaper_Turbocharging_2014.pdf US Environmental Protection Agency. 2016. Global Greenhouse Gas Emissions Data. Retrieved from https://www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data Read More

Rankine cycle Hossain and Bari (2014) utilized Rankine Cycle to improve efficiency of a 4o kW diesel engine generator. The research was premised on shell and tube heat exchanger through the use of water and two organic fluids: Ammonia and HFC-134a. Hossain and Bari (2014) found out the use of heat exchanger can improve the efficiency of the engine by 10% (water), 9% (Ammonia) and 8% (HFC-134a). Without going into the specifics of the processes, it is evident that the use of Rankine Cycle can improve the efficiency and performance of any engine.

The following image summaries the Rankine cycle: Source (Kapooria, Kumar and Kasana, 2008) Wang et al. (2013) proposes a thermal efficient model that incorporates the design of organic Rankine cycle in improving efficiency and performance in the optimal operation condition and thermal efficacy. Based on the model, Wang et al. (2013) states that the performance of organic Rankine cycle depends on the working fluid, since the fluid should have high vaporization latent, low specific liquid heat and low critical temperature (Ayodele and Kahn, 2014).

These assertions indicates the importance of Rankine cycle in recovering waste noise and heat in improvement of engine and other energy sources efficiency. Six stroke IC engine and Turbocharger Technology Saidur et al. (2012) discusses a six-stroke form of an engine that combines the basic four stroke engine with additional two cycles to reduce emissions while producing higher efficiency. Saidur et al. (2012) states some researchers such as Hayasaki et al. proposes a model that incorporates a second compression systems are opposed to the traditional four-stroke diesel system.

A normal four stroke cycles has four components, which are the exhaust stroke, combustion stroke, compression stroke and intake stroke. The argument is the exhaust from the four strokes are captured and processed through the additional two strokes (Markides, 2013). The design also enable strapping of exhaust through inclusion of water and the process involves expansion activities that improves the efficiency and performance activities. The effectiveness can be improved further through valve closing timing and modification of the engine in an ideal thermodynamics model.

A naturally aspirated engine produces large amounts of waste heat and can be recovered through the use of turbocharger. The effectiveness of a turbocharger depends on the supercharger that employs an exhaust system design (Wang et al. 2011). The ideology behind the turbocharger is using the pressure and heat occurring in the expanding exhaust gas to improve the efficiency of the engine power. The components that make up a turbocharger includes center housing and rotating assembly, actuator, waste gate valve, compressor, shaft and turbine (Liu et al., 2015). The design increases power density and engine downsizing resulting in increase in engine efficiency.

Even though turbocharger is an effective approach in recovering energy from heat waste, Saidur et al. (2012) highlights numerous challenges. The challenges in the automotive industry include turbo lag (i.e. transient response and hesitation) during low accelerations and consequences of heated bearings. The turbo large inhibits the performance and drivability of the engine. The problems associated with the turbo lag are associated with the numerous equipment in the design process and reduction in useful turbine energy.

The proposed solution to the problem is use of 2-stage turbocharger to address the challenges (Wang et al. 2013). The change of the design results in minimization of the turbo lag, improved dynamic performance, better low end torque, low pressure stage efficiencies and higher power outputs. It illustrates that the turbocharger is an effective strategy, which may be employed in addressing heat wastes from automotive engines. The following image shows the components that forms turbo technology: Source (MTU 2016) The Benefit of Converting Exhaust Waste Heat and Noise Apart from the demand for the society and environment, converting exhaust waste into forms of energy has numerous benefits.

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