Mathematical Modelling, Finite Element Simulation and Experimental Validation of Biogas-digester Slurry Temperature
International Journal of Energy and Power Engineering
Volume 2, Issue 3, June 2013, Pages: 128-135
Received: Jul. 8, 2013; Published: Jul. 20, 2013
Views 3511      Downloads 247
Authors
Suresh Baral, School of Engineering, Pokhara University, Kaski, Nepal
Shiva P. Pudasaini, Department of Mechanical Engineering, Kathmandu University, Kavre, Nepal
Sanjay Nath Khanal, Department of Mathematical Sciences, Kathmandu University, Dhulikhel, Kavre, Nepal
Dil Bahadur Gurung, Department of Environmental Science and Engineering, Kathmandu University, Dhulikhel, Kavre
Article Tools
PDF
Follow on us
Abstract
The present describes and simulates the temperature distribution of slurry by using the heat equation and appropriate boundary conditions and their numerical simulations with the Finite Element Method. This method is suitable to describe the temperature profile in Bio-digester and Bio-rectors for optimum biogas production. The Mathematical modeling of bio-digester helps us to understand the change in digester temperature with the change in the ambient temperature, internal heat generation, thermal conductivity and other physical and thermo-dynamical processes that govern the thermal system. Mathematical modeling can also be used to predict and estimate the physical and chemical parameters affecting the biogas production. The internal heat generation was estimated to be 1.2 W/m3.The Finite Element linear, quadratic solutions and exact solution was compared for the profile of temperature of the bio-digester slurry. The average temperature of bio-digester slurry was found to be 33.12 °C at its center. The thermal conductivity we have also found to be 0.69 W/ m °C. By using the finite element method to solve the mathematical modeling, the maximum slurry temperature was found to be 33.13 °C at its center. Furthermore, we have calculated the thermal conductivity in the biogas chamber from our measurement data. This thermal conductivity (k) 0.69 W/m °C was used in the exact solution of the physical model equation, linear and quadratic finite elements solutions. The temperature profiles of these three solutions virtually collapse to a single parabolic profile, which in term agreed very well with our measured data of the temperature profile.
Keywords
Mathematical Modeling, Slurry Temperature, Thermal Conductivity, Biogas-Digester, Finite Element Method, Internal Heat Generation
To cite this article
Suresh Baral, Shiva P. Pudasaini, Sanjay Nath Khanal, Dil Bahadur Gurung, Mathematical Modelling, Finite Element Simulation and Experimental Validation of Biogas-digester Slurry Temperature, International Journal of Energy and Power Engineering. Vol. 2, No. 3, 2013, pp. 128-135. doi: 10.11648/j.ijepe.20130203.17
References
[1]
Katuwal, Hari, and Alok K. Bohara. "Biogas: A promising renewable technology and its impact on rural households in Nepal." Renewable and Sustainable Energy Reviews 13.9 (2009): 2668-2674.
[2]
Gautam, Rajeeb, Sumit Baral, and Sunil Herat. "Biogas as a sustainable energy source in Nepal: Present status and future challenges." Renewable and Sustainable Energy Reviews 13.1 (2009): 248-252.
[3]
Biswas, J., R. Chowdhury, and P. Bhattacharya. "Mathematical modeling for the prediction of biogas generation characteristics of an anaerobic digester based on food/vegetable residues." Biomass and Bioenergy 31.1 (2007): 80-86.
[4]
Rapport, J. L., Zhang, R., Jenkins, B. M., Hartsough, B. R., & Tomich, T. P."Modeling the performance of the anaerobic phased solids digester system for biogas energy production." Biomass and Bioenergy35.3 (2011): 1263-1272.
[5]
Li, Chenxi, Pascale Champagne, and Bruce C. Anderson. "Evaluating and modeling biogas production from municipal fat, oil, and grease and synthetic kitchen waste in anaerobic co-digestions." Bioresource technology 102.20 (2011): 9471-9480.
[6]
Zashkova, Liliana, Nina Penkova and Rositza Karamfilowa."Heat transfer processes in a biogas-reactor." Task Quarterly 9.4 (2005): 427-438.
[7]
Mittal, K. M. Biogas systems: principles and applications. New Age International Limited Publishers, 1996.
[8]
Rao, Singiresu S. "The finite element method in engineering." (1986).
[9]
Reddy, Junuthula Narasimha. An introduction to the finite element method. Vol. 2. No. 2.2. New York: McGraw-Hill, 1993.
[10]
DeWalle, Foppe B., Edward Hammerberg, and Edward SK Chian. "Gas production from solid waste in landfills." Journal of the Environmental Engineering Division 104.3 (1978): 415-432.
[11]
Reinhart, Debra R., and A. Basel Al-Yousfi. "The impact of leachate recirculation on municipal solid waste landfill operating characteristics." Waste Management & Research 14.4 (1996): 337-346.
[12]
Kayhanian, M., and S. Hardy. "The impact of four design parameters on the performance of a high‐solids anaerobic digestion of municipal solid waste for fuel gas production." Environmental technology 15.6 (1994): 557-567.
[13]
Lee, J. J., Jung, I. H., Lee, W. B., & Kim, J. O."Computer and experimental simulations of the production of methane gas from municipal solid waste." Water Science & Technology 27.2 (1993): 225-234.
ADDRESS
Science Publishing Group
1 Rockefeller Plaza,
10th and 11th Floors,
New York, NY 10020
U.S.A.
Tel: (001)347-983-5186