Effect absorber plate geometry on the performance of collector-cum-storage type solar water heater

Abstract

Three built-in-storage type solar water heaters of equal volume are tested under identical conditions for performance evaluation. One of these .water heaters is flat absorber plate and the other two are rectangular corrugated absorber plate and trapezoidal corrugated absorber plate. The test is carried out during the month of March, April, July and August 2001 at Dhaka. The rectangular corrugated absorber plate collector heats water up to 69°C and nOc in the month of March and April whereas flat absorber plate collector heats up to 63.5°C and 66°C respectively. The maximum water temperatures are found to be 61°C and 66°C for trapezoidal corrugated absorber plate and 57°C and 61.50C for flat absorber plate collector for the month the July and August respectively. The average efficiency is found to be 76% in the month of March and 79% in the month of April for rectangular corrugated absorber plate collector, whereas that of flat absorber plate is 64% and 66% in the month of March and April respectively. The average efficiency is 73% and 62% for trapezoidal corrugated absorber plate collector and flat absorber plate collector, respectively.