http://www.iaeme.com/IJMET/index.asp 39 editor@iaeme.com International Journal of Mechanical Engineering and Technology (IJMET) Volume 7, Issue 2, March-April 2016, pp. 39-44, Article ID: IJMET_07_02_005 Available online at http://www.iaeme.com/IJMET/issues.asp?JType=IJMET&VType=7&IType=2 Journal Impact Factor (2016): 9.2286 (Calculated by GISI) www.jifactor.com ISSN Print: 0976-6340 and ISSN Online: 0976-6359 © IAEME Publication THEORETICAL AND EXPERIMENTAL STUDIES ON STEPPED SOLAR STILL Vivek Sachan and Ajeet Kumar Rai Department of Mechanical Engineering, SSET, SHIATS – Allahabad, U.P. India ABSTRACT In the present work, an attempt has been made to study the performance of a solar still. Many thermal models were developed by researchers to predict the performance of solar still. Thermal models developed by Dunkle and by Tsilingiris to predict the performance of the still is considered for the present study. A stepped solar still is fabricated for experimental study in the premises of SHIATS Allahabad (U.P.) India. It is observed that the daily productivity of more than 5 kg is obtained by still area of 1 m 2 . It is further observed that the daily productivity predicted by Tsilingiris model is closer than the Dunkle model. Cite this Article: Vivek Sachan and Ajeet Kumar Rai, Theoretical and Experimental Studies on Stepped Solar Still, International Journal of Mechanical Engineering and Technology, 7(2), 2016, pp. 39-44. http://www.iaeme.com/currentissue.asp?JType=IJMET&VType=7&IType=2 1. INTRODUCTION Water is precious to life. Often water sources are brackish containing harmful bacteria and therefore cannot be used for drinking. Distillation is the one of processes that can be used for water purification. Desalination refers to the process of removing salt and other minerals from water. Water is desalinated in order to convert salt water to fresh water which is suitable for human consumption. Various research works are being carried out to improve the performance of the still. The basin area of the still, free surface area of water, inlet temperature of water, wind velocity, solar radiation, depth are some of the factors that affect the productivity of the solar still. Moustafa et al (1979) carried out experimental studies on stepped solar still to improve the efficiency of the still by reducing the radiation losses from the basin. Suleiman (2007) studied the effect of water depth on productivity to show that a higher productivity was obtained for a low water depth. Velmurugan and Srithar (2007) used sponge cubes in the still to improve the productivity by 57.8% than the conventional still. Velmurugan et al. (2009) worked with an industrial effluent in a fin type single slope solar still and a stepped solar still separately. The maximum output was found in the fin type solar still. A new design of a stepped solar desalination system with a flashing chamber was experimentally investigated by El-Zahaby et al. (2010). In the present work a stepped