# Numerical Solution and it’s Analysis during Solar Drying of Green Peas

• Arunsandeep Godireddy
• Abhay Lingayat
• Razat Kumar Naik
• V. P. Chandramohan
• V. Rajesh Kanan Raju
Original Contribution

## Abstract

A mathematical model is developed for solar drying of green peas (Botanical name: Pisum Sativum). The problem is solved assuming the shape of the green peas is spherical. The governing transient mass transfer equation is discretized into finite difference scheme. The time marching is performed by implicit scheme. The governing equations and boundary conditions are non-dimensionalized to get generic results. The product in the chamber is in contact with air which is heated by solar energy, so the boundary conditions of third kind (convective boundary conditions) are considered. By space and time discretization a set of algebraic equations are generated and these algebraic equations are solved by tridiagonal matrix algorithm. A computer code is developed in MATLAB in order to compute the transient moisture content distribution inside the product. Center point, boundary and mean moisture of green peas are estimated at different temperatures and drying time. Present numerical result is compared with experimental result from literature and it was found that there is a good agreement of results. The drying time is predicted for how quickly the mean moisture of green peas is reached to 50, 40, 30, 20 and 10% of its initial moisture corresponding to different temperatures.

## Keywords

Solar drying Finite difference method (FDM) Implicit scheme Tridiagonal matrix algorithm MATLAB

## Notations

D

Coefficient of diffusion, m2/s

M

Moisture content of the product, kg/kg of db

Mair

Moisture content of the air, kg/kg of db

Mo

Initial moisture content, kg/kg of db

r

Space coordinate, m

R

t

Time coordinate, s

hm

Mass transfer coefficient, m/s

T

Temperature, °C

## Superscript

*

Non dimensional parameter

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© The Institution of Engineers (India) 2017

## Authors and Affiliations

• Arunsandeep Godireddy
• 1
• Abhay Lingayat
• 1
• Razat Kumar Naik
• 1
• 2
• V. P. Chandramohan
• 1
• V. Rajesh Kanan Raju
• 1
1. 1.Department of Mechanical EngineeringNational Institute of Technology WarangalWarangalIndia
2. 2.Raz TechnologiesThanapara, SundargarhIndia