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
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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
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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.
Mathematical Modeling, Slurry Temperature, Thermal Conductivity, Biogas-Digester, Finite Element Method, Internal Heat Generation
To cite this article
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.
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