ORCID Profile
0000-0002-1376-3379
Current Organisation
University of South Australia
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: ASME International
Date: 21-10-2013
DOI: 10.1115/1.4025345
Abstract: High temperature diesel engine exhaust gas can be an important source of heat to operate a bottoming Rankine cycle to produce additional power. In this research, an experiment was performed to calculate the available energy in the exhaust gas of an automotive diesel engine. A shell and tube heat exchanger was used to extract heat from the exhaust gas, and the performance of two shell and tube heat exchangers was investigated with parallel flow arrangement using water as the working fluid. The heat exchangers were purchased from the market. As the design of these heat exchangers was not optimal, the effectiveness was found to be 0.52, which is much lower than the ideal one for this type of application. Therefore, with the available experimental data, the important geometric aspects of the heat exchanger, such as the number and diameter of the tubes and the length and diameter of the shell, were optimized using computational fluid dynamics (CFD) simulation. The optimized heat exchanger effectiveness was found to be 0.74. Using the optimized heat exchangers, simulation was conducted to estimate the possible additional power generation considering 70% isentropic turbine efficiency. The proposed optimized heat exchanger was able to generate 20.6% additional power, which resulted in improvement of overall efficiency from 30% to 39%. Upon investigation of the effect of the working pressure on additional power generation, it was found that higher additional power can be achieved at higher working pressure. For this particular application, 30 bar was found to be the optimum working pressure at rated load. The working pressure was also optimized at part load and found that 2 and 20 were the optimized working pressures for 25% and 83% load. As a result 1.8% and 13.3% additional power were developed, respectively. Thus, waste heat recovery technology has a great potential for saving energy, improving overall engine efficiency, and reducing toxic emission per kilowatt of power generation.
Publisher: IntechOpen
Date: 14-01-2019
Abstract: Rotating detonation engines are a novel device for generating thrust from combustion, in a highly efficient, yet mechanically simple form. This chapter presents a detailed literature review of rotating detonation engines. Particular focus is placed on the theoretical aspects and the fundamental operating principles of these engines. The review covers both experimental and computational studies, in order to identify gaps in current understanding. This will allow the identification of future work that is required to further develop rotating detonation engines.
Publisher: European Respiratory Society
Date: 28-09-2019
Publisher: Elsevier BV
Date: 02-2019
Publisher: SAE International
Date: 08-04-2013
DOI: 10.4271/2013-01-1639
Publisher: Elsevier BV
Date: 02-2019
Publisher: American Society of Mechanical Engineers
Date: 11-11-2019
Abstract: Due to skyrocketing fuel price and demand, engine manufacturers and researchers have been thriving to find alternative sources of fuel for internal combustion engines. Biodiesel and vegetable-based fuels are prospective substitutes for petro-diesel fuel for compressions ignition (CI) or diesel engines, and favourable over petro-diesel fuel in terms of sustainability and environmental friendliness. It is found from the literatures that higher viscous fuels (HVFs) and biodiesel fuels have substandard engine performance and emissions especially in the case of brake specific fuel consumption (BSFC), torque and NOx emissions compared to those of the engines using petro-diesel. This is mainly due to their higher viscosity and density as well as lower volatility and calorific value and thus, they are termed as higher viscous fuels. Furthermore, the higher viscosity and density of HVFs retard the combustion efficiency since HVFs are less prone to evaporate, diffuse and mix properly with the in-cylinder air. Based on these findings, researchers have put effort into improving the performance of CI engines running with HVFs. Generally, three techniques are very popular by the researchers, namely, blending the HVFs with petro-diesel (known as fuel blend), preheating the HVFs, and altering the injection strategy from the original engine-settings for petro-diesel operation. In this paper, a comprehensive review is presented on these techniques to improve the performance of CI engines run on HVFs.
Publisher: S. Karger AG
Date: 2019
DOI: 10.1159/000501283
Abstract: b i Background: /i /b When introducing new equipment or reference equations into the lung function laboratory, systematic i z /i -score deviations could arise due to local differences in population or equipment. b i Objective: /i /b To propose a workable method for aligning reference equations with lung function equipment. b i Method: /i /b Using two cases of equipment transition in our laboratory as a test case, we first performed lung function testing after the transition, on a control group of 40 normal young adults (20 male/20 female 20–30 years old). For those indices with an average i z /i -score in excess of ±0.5, adapted reference values were obtained by an offset or scaling factor on the M coefficient with the so-called lambda-mu-sigma (LMS) method recommended by the Global Lung Function Initiative, and the i z /i -scores were computed again. b i Results: /i /b Following a transition involving instrumental dead space reduction, the lung clearance index was predictably reduced, resulting in a mean (±SD) i z /i -score of –1.9 (±1.1) in the control group by adapting the reference values with an offset on M, the i z /i -score became –0.1 (±1.1). Applying the same method to a transition of standard lung function equipment, the i z /i -scores became centered around zero in the control group, but also became properly aligned in a test group of 81 other subjects spanning a wider age range (20–80 years). b i Conclusions: /i /b We proposed and verified a method for aligning local equipment with reference values obtained elsewhere, or following a local change in equipment. The key is to measure a relatively small young adult group, identifying those lung function indices that need adaptation based on i z /i -scores, in order to then obtain laboratory-specific reference values that can be applied over the entire age range.
Publisher: American Society of Mechanical Engineers
Date: 13-11-2015
Abstract: The heat from the exhaust gas of diesel engines can be an important heat source to provide additional power and improve overall engine efficiency. Studies related to the applications of recoverable heat to produce additional power using separate Rankine cycle are scare. To recover heat from the exhaust of an engine, an efficient heat exchanger is necessary. For this type of application, the heat exchangers are needed to be designed in such a way that it can handle the heat load with reasonable size, weight and pressure drop. In this project, experiments were conducted to measure the exhaust heat available from a 40 kW diesel generator at different loads. Shell and tube heat exchangers were purchased and installed into the engine. The performance of the heat exchangers using water as the working fluid was then conducted. With the available data, computer simulation was carried out using CFD software CFX to improve the design of the heat exchangers. Geometric variables including length, number and diameter of tubes, and baffle design were all tested separately. Upon investigating how these parameters influenced the heat exchangers’ effectiveness, optimum design of shell and tube heat exchangers was proposed. The proposed heat exchangers were manufactured and experiment was conducted. Two heat exchangers were used to generate superheated steam. These two heat exchangers were arranged in two orientations namely, series and parallel. The proposed heat exchanger was able to produce 2.71 kW additional power using water as the working fluid at an optimum working pressure of 15 bar using parallel arrangement. It was found that parallel arrangement generated 10% more additional power than the series arrangement.
Publisher: SAE International
Date: 04-2014
DOI: 10.4271/2014-01-0677
Publisher: Elsevier BV
Date: 11-2013
Publisher: Elsevier BV
Date: 2015
Publisher: Elsevier BV
Date: 2014
Publisher: Elsevier BV
Date: 11-2013
Publisher: American Society of Mechanical Engineers
Date: 15-11-2013
Abstract: The heat from exhaust gas of diesel engines can be an important heat source to provide additional power and improve overall engine efficiency. Bottoming Rankine Cycle (RC) is one of the promising techniques to recover heat from the exhaust. One derivative of RC known as Organic Rankine Cycle (ORC) is also suitable for heat recovery for moderate and small size engines as the exhaust heat content and temperature of these engines are low. To recover heat from the exhaust of the engine, an efficient heat exchanger is necessary. In this current research, a shell and tube heat exchanger is optimized by computer simulation for two working fluids, water and HFC-134a. Two shell and tube heat exchangers were purchased and installed into a 40 kW diesel generator. The performance of the heat exchangers using water as the working fluid was then conducted. With the available data, computer simulation was carried out using CFD software ANSYS CFX14.0 to improve the design of the heat exchanger for both fluids. Geometric variables including length, number of tubes, and baffle design are all tested separately. Using the optimized heat exchangers simulation was conducted to estimate the possible additional power generation considering 80% isentropic turbine efficiency. The proposed heat exchanger was able to produce 11% and 9.4 % additional power using water and HFC-134a as the working fluid at maximum working pressure of 15 and 40 bar respectively. This additional power results into 12% and 11% improvement in brake-specific fuel consumption (bsfc) by using water and HFC-134a respectively. This indicates that besides water, organic fluids can also be a suitable option to recover heat from the exhaust of diesel engine.
Publisher: Elsevier BV
Date: 03-2020
Publisher: Elsevier BV
Date: 2013
No related grants have been discovered for Shekh Hossain.