PERFORMANCE IMPROVEMENT OF TRADITIONAL JAGGERY MAKING PROCESS:

A NUMERICAL APPROACHUnder the guidance of

Prof. M. Mohan Jagadeesh KumarAssociate Professor

School Of Mechanical Engineering

V. Aravind Ram Sharma14MEE0050

M.Tech Energy & Environment EngineeringSCHOOL OF CIVIL & CHEMICAL ENGINEERING

Jaggery Making:

Juice Extraction

• The sugarcane harvested is taken into millers and crushed to extract juice.

• This sugarcane juice is tested for visible impurities and taken for further process comprising of its heating.

Boiling

• The sugarcane juice is allowed to be heated/boiled in a pan kept on an open hearth furnace.

• Boiling changes the properties of the juice resulting in change of its phase.

• Chemicals are added in the midst to remove the molasses formed during boiling.

• The semi solid juice is taken out of the pan and prepared for the next step i.e.; Drying/packing.

Packing

• The Semi solid juice is poured into moulds of respected sizes and shapes.

• The Juice is allowed to dry in a cool and dry place resulting in the hardening and thus formation of jaggery.

• Once the jaggery are completely dried they are taken out of moulds and packed in various packages and sent out for marketing.

Problem Definition:• Considering the heat transfer happening there is a major amount of heat that

goes un used.• The traditional process seems to be outdated with no focus on improvement in

heat transfer or energy utilization but only on the ease of use.• The concentration is only on production of jaggery and not on utilization of the

fuel to maximum.• Additionally this accounts for poor cost utilization also.

Earlier Studies:Previously studies were conducted on the jaggery making process and techniques were proposed in order to improve the overall efficiency. Among them are the following:1. Usage of fins in order to increase the heat transfer area for effective heating.2. Utilization of more than one pan where the heat from flue gases from the

primary pan are used to heat the secondary pans.3. Minor change in the geometry of the pan to increase the heat gained.

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Need & Objective of the study:• Any improvement done to the heat transfer rate result in the effective utilization of

the fuel(bagasse) which can be later used in other industries such as paper industry.

• Fuel efficiency holds importance and any process that saves fuel is implementable.

• The study finds what amount of heat transfer takes place in the normal process and the process where modifications in design are made.

• The project aims at reporting the effect of modifications made on the increase in the effectiveness.

Methodology:• The methodology involves developing of the model of the pan which is done

using the ANSYS modeler involved in the CFD tool itself.• A 2-D model of the pan in its different geometries is made based on the

dimensions in the literature.• The dimensions are scaled down in order to ease out the process of meshing.• Meshing parameters are taken of the order of 1e-04 size. • The model is kept as simple as possible to avoid large time taken for analysis.

Meshing:• The size considered was 1e-04 for meshing.

• The meshing is of no bias type with hard mesh and quadrilateral meshing is used.

• The sizing taken was of Edge sizing in every geometry.

Boundary conditions:• Boundary conditions implemented were based on the real time conditions.

• The heat flux value was based on the calorific value of the fuel.

• The walls were considered to be of radiative conditions.

• The emissivity values were considered taking from 0.7 to 0.95 and the results for a value of 0.9 are displayed.

Boundary Condition

Top Pressure Outlet, Backflow temperature of 300K

Left Radiative wall with emissivity =0.7, Freestream temperature = 300K

Right Radiative wall with emissivity =0.7, Freestream temperature = 300K

Bottom Heat flux = 2000W/m2

Results:• The included the temperature contours of the different conditions assumed and

the temperature ranges.

Temperature contours of traditional pan

Min = 301K; Max = 322K Min = 307K; Max = 333K

Min = 329K; Max = 363K

Min = 395K; Max = 456KTemperature contours of traditional pan

Temperature contours of pan with rectangular fins

Min = 302K; Max = 330K

Min = 310K; Max = 338K

Min = 331K; Max=366K

Min = 387K; Max = 435K

Temperature contours of pan with triangular fins

Min = 303K; Max = 326K

Min = 310K; Max = 338K

Min = 331K; Max = 365K

Min = 388K; Max = 435K

Temperature contours of pan with additional surface

Min = 308K; Max = 351K

Min = 324K; Max = 375K

Min = 359K; Max = 416KMin = 375K; Max = 435K

Temperature contours of pan with cut out surface

Min = 310K; Max = 347K

Min = 330K; Max = 373K

Min = 369K; Max = 421K

Min = 386K; Max = 442K

Temperature contours of pan 25% filled

Min = 349K; Max = 370K

Min = 400K; Max = 435K

Min = 314K; Max = 334K

Min = 335K; Max = 361K

Min = 398K; Max = 448K

Temperature contours of pan 50% filled

Inference:• The contours displays the temperature profile inside the pan during the initial

condition where the heat transfer takes place and the final stage where the combustion is stopped.

• The dispersion of temperature along the length and width of the pan decides the efficiency of the design modification.

• Also temperature difference for a certain model shows whether heat is dissipated properly or not.

• The temperature dispersion shows that adding fins does improve the heat transfer by maintaining even temperature along the pan than the traditional approach.

• Also additional surfaces added and cut out does make a positive impact the improvisation of heat transfer.

Conclusion:• Finally the traditional pan design which is considered to be less efficient in

extracting the heat from an open hearth furnace can be made effective with modifications in the design.

• The changes can be noted as adding fins and additional surface for heat transfer improvement.

• The improvement in heat transfer results in the decreased usage of fuel per batch thus optimizing the energy efficiency.

• Many other improvements are to be studied in knowing which can be the optimized design for maximum efficiency and experimentation are also to be conducted in order to validate the results.