PDF Publication Title:
Text from PDF Page: 008
5656 R. Saidur et al. / Renewable and Sustainable Energy Reviews 16 (2012) 5649–5659 compressing the air that goes into the engine’s combustion chambers. The turbine blades of the pump will be spun by the hot exhaust gases leaving the cylinders. A turbocharger compo- nent usually made up of (1) turbine, (2) shaft, (3) compressor, (4) waste gate valve, (5) actuator and (6) center housing and rotating assembly (CHRA). Fig. 9 shows a typical turbocharger. Turbocharger technology make possible for engine downsizing through reducing pump work in SI engines. Also, its ability to increase power density greatly influences the revival of diesel engines into the industry in which most of diesel engines today are equipped with turbochargers. Turbocharging increases the air mass flow rate into the engine which significantly reduces particulates for diesel engines that are released into the atmo- sphere. Furthermore, it has been reported that turbocharged diesel engine can improve the fuel economy of passenger vehicles up to 30–50% and downsized turbocharged gasoline engine by 5–20% [86]. Turbocharging was largely adopted in diesel engines and recent motivation for more fuel efficient, economic and high- performance engines. Turbo charging has also slowly been estab- lished with gasoline engines although the demands are dissimilar to that of diesel engines. 5.2. Challenges of turbocharger The earliest development of exhaust-driven turbocharger was recordedbyDr.AlfredJ.Bu ̈chiinSwitzerlandbetween1909and 1912. In 1915, he proposed the first turbocharged diesel engine but gain no interests from the community [87]. In its early infancy, turbochargers were utilized mostly in heavy-duty appli- cations. Traditionally, turbochargers had two important issues which are the main reasons for its low acceptance in the automotive industry. Turbochargers suffer turbo lag (i.e., hesita- tion or transient response) during low speed acceleration and there are major concerns with heated bearings. Turbo lag can poorly affect the drivability and performance of the engine. Park et al. [88] studied the mechanism of a turbocharger response delay and stated that the interruption of boost pressure response is due to a combination of issues. The primary reason is due to the physical properties of the turbocharger systems i.e., weights of the turbine and compressor. The secondary reason (which is a resultant problem of primary factor) is mainly due to the reduced useful turbine energy occurred from disturbances in the operating mechanism. To improve the transient response, weights of turbine and compressor wheel can be reduced by using new materials. Additionally, reducing intake and exhaust system volume may also improve transient response of the turbocharger. 5.2.1. Variable geometry turbine—Reducing turbo lag Variable Geometry Turbocharger (VGT) technology (also known as Variable Nozzle Turbocharger, VNT) is a type of turbine where the turbo controls the exhaust flow through the turbine blades by using variable vanes. At low engine speeds, the effective aspect ratio (A/R) is too large and the turbo will not be able to produce boost. Conversely, at high engine speeds, the A/R ratio is too small for the turbo which will choke the engine. As a result, increase in exhaust manifold pressures, high losses in pumps and eventually lower power output. A turbocharged engine equipped with VGT has small movable vanes to direct the incoming exhaust flow through the turbine blades. At different ranges of speed, the angle of the vanes would vary to optimize the flow of the exhaust gas. There are various articles discussing VGTs. Shimizu et al. [89] examined the torque control of a small gasoline engine that was equipped with a VNT turbocharger. Authors reported torque improvement of about 27% at lower speed. Wang et al. [90] designed an electronic control for a VNT turbocharger which they demonstrated to have a good performance of pressure boost control under steady and transient conditions. Andersen et al. [91] investigated and benchmarked six closely matched turbo- charged SI engines that are equipped with VGTs. They tested various engine operations and conditions including engine per- formance during low and high engine speeds, transient response and flow capacity. They concluded that more than 10% improve- ment were achieved during low and high engine speed torque for VGTturbochargerscomparedtofixedgeometryturbochargers. Eichhorn et al. [92] explored the use of a turbocharger equipped with VNT to power auxiliary load i.e., the air conditioning system by using WEDACS (Waste Energy Driven Air Conditioning System). This system uses the turbine to produce mechanical energy and cold air. The mechanical energy is then converted into electrical energy by using an alternator while the cold air is used to cool the air conditioning fluid. The results show that from a 2 l engine, 50 W to 1.3 kW of power could potentially be recovered. 5.3. Recent developments of turbocharger 5.3.1. Two-stage turbocharger An exciting development of turbocharger technology is the introduction of a revolutionary -stage turbocharger. Basically, a two-stage turbocharger has two different sized turbochargers assembled in serial configuration. The smaller sized turbocharger responds at lower speed by producing a higher torque that will reduce fuel consumption on the road [93]. Furthermore, the larger unit provides boost at higher engine speeds [93]. Based on the cluster of engines, different characteristic ranges of different Fig. 9. Typical turbocharger with compressor wheel and turbine [85].PDF Image | Heat Condensing Operating Parameters ElectraTherm
PDF Search Title:
Heat Condensing Operating Parameters ElectraThermOriginal File Name Searched:
Dr.Saidur_Techn.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)