Evaporative heat transfer and enhancement performance of rib-roughened tube annuli with refrigerant 114

1994 ◽  
Vol 37 (3) ◽  
pp. 425-436 ◽  
Author(s):  
Mao-Yu Wen ◽  
Shou-Shing Hsieh
Author(s):  
Ajay Kumar Kaviti ◽  
Akkala Siva Ram ◽  
Amit Kumar Thakur

In this experimental study, permanent magnets with three different sizes (M-1: 32 mm inner diameter, 70 mm outer diameter and 15 mm thick, M-2: 25 mm inner diameter, 60 mm outer diameter and 10 mm thick, M-3: 22 mm inner diameter, 45 mm outer diameter and 9 mm thick) are fully submerged in the single-slope glass solar still. The performance of magnetic solar stills (MSS) with three different sizes at 2 cm depth water to ensure that magnets are fully submerged is compared with conventional solar still (CSS) at the location 17.3850°N, 78.4867°E. Tiwari model is adapted to calculate the heat transfer coefficients (HTC), internal and exergy efficiencies. MSS with M-1, M-2 and M-3 significantly enhanced the convective, radiative, and evaporative heat transfer rate for the 2 cm depth of water. This is due to the desired magnetic treatment of water, which reduces the surface tension and increases the hydrogen bonds. The MSS's total internal HTC, instantaneous efficiencies led CSS by 25.52%, 28.8%, respectively, with M-1. Having various magnetic fields due to different magnets sizes increases MSS's exergetic efficiency by 33.61% with M-1, 33.76% with M-2, and 42.25% with M-3. Cumulative yield output for MSS with M-1, M-2, and M-3 is 21.66%, 17.64%, 15.78% higher than CSS. The use of permanent magnets of different sizes in the MSS is a viable, economical and straight forward technique to enhance productivity.


1998 ◽  
Vol 35 (9) ◽  
pp. 671-678 ◽  
Author(s):  
Md. Shafiqul ISLAM ◽  
Ryutaro HINO ◽  
Katsuhiro HAGA ◽  
Masanori MONDE ◽  
Yukio SUDO

Sign in / Sign up

Export Citation Format

Share Document