Exergy Analysis of Heat Pump Dryer
doi: 10.14456/mijet.2018.3
Keywords:
Availability, Exergy efficiency, ginger, irreversibilityAbstract
Exergy analysis was based on five components; exergy calculation of the drying medium cycle, vaporization at ginger and evaporator, refrigeration cycle and electricity. Drying medium temperature plays the important role in calculation of exergy, therefore the measured inlet and outlet temperatures for the system was used for the drying medium cycle exergy calculation. The inlet and outlet refrigerant temperatures were used for exergy calculation of the refrigeration cycle based on the R-22 pressure-enthalpy diagram. The refrigerant was cycled through evaporator to compressor, condenser and expansion valve. Exergy of the electricity was found from the energy irrespective of drying time at heater, compressor and blower: only system exergy inflow was considered. Exergy inflow, outflow and loss were determined for the whole system and exergy efficiency then calculated. Ginger drying by 50˚C air had the highest exergy efficiency at 28 %, followed with 60˚C air at 24 %.
References
thin layer drying of mulberry in a forced solar dryer. Energy, 35,
2010, p. 1754-1763.
[2] MUJUMDAR A. S. Handbook of industrial drying. vol. 2. New
York, Marcel Dekker Inc., 2005.
[3] QUEIROZ R., GABAS A. L., and TELIS V. R. N. Drying kinetics
of tomato by using electric resistance and heat pump dryers.
Drying Technology, 22(7), 2004, p. 1603-1620.
[4] SARKER M.S.H., IBRAHIM M.N. AZIZ N.A., and PUNAN M.S.
Energy and exergy analysis of industrial fluidized bed drying of
paddy. Energy, 84, 2015, p. 131-138.
[5] PAL U. S. and KHAN M. K. Calculation steps for the design of
different components of heat pump dryers under constant drying
rate condition. Drying Technology, 26, 2008, p. 864-872.
[6] ADAPA P. K., SOKHANSANJ S., and SCHOENAU G. J.
Performance study of a recirculating cabinet dryer using a
household dehumidifier. Drying Technology, 20(8), 2002, p.
1673-1689.
[7] SOSLE V., RAGHAVAN G. S. V., and KITTLER R. Lowtemperature
drying using a versatile heat pump dehumidifier.
Drying Technology, 21(3), 2003, p. 539-554.
[8] YUMRUTAS R., KUNDUZ M., AND KANOGLU M. Exergy
analysis of vapor compression refrigeration systems. Exergy, an
International Journal, 2, 2002, p. 266-272.
[9] CHEN J., HAVTUN H., and PALM B. Conventional and
advanced exergy analysis of an ejector refrigeration system.
Applied Energy, 144, 2015, p. 139-151.
[10] CENGEL Y. A. Heat and Mass Transfer: A practical Approach.
3rd edition. Singapore, McGraw-Hill, 2006.
[11] AKPINAR E.K., MIDILLI A., and BICER Y. Energy and exergy
of potato drying process via cyclone type dryer. Energy
Conversion and Management, 46, 2005, p. 2530-2552.
[12] AKPINAR E. K., MIDILLI A., and BICER Y. The first and
second law analyses of thermodynamic of pumpkin drying
process. Journal of Food Engineering, 72, 2006, p. 320-331.
[13] SELWYNRAJ A. I., INIYAN S., POLONSKY G., SUGANTHI L.,
and KRIBUS A. Exergy analysis and annual exergetic
performance evaluation of solar hybrid STIG (steam injected gas
turbine) cycle for Indian conditions. Energy, 80, 2015, p. 414-427.
[14] DINCER I., and SAHIN A. Z. A new model for thermodynamic
analysis of a drying process. International Journal of Heat and
Mass Transfer, 47, 2004, p. 645-652.
[15] CEYLAN I., AKTAS M., and DOGAN H. Energy and exergy
analysis of timber dryer assisted heat pump. Applied Thermal
Engineering, 27, 2007, p. 216-222.
[16] SARKER M. S. H., IBRAHIM M. N. AZIZ N.A., and PUNAN M.
S. Energy and exergy analysis of industrial fluidized bed drying of
paddy. Energy, 84, 2015, p. 131-138.
