ABSTRACT
The work aims to analyse an ejector refrigeration system powered with solar energy through serially connected collectors to lower greenhouse gases. The collectors chosen for the work are Scheffler and parabolic collectors with an area of 2.5 m2 and 6 m2, respectively. The steam generated by the collectors is stored temporarily in a 15-l storage tank. The thermic fluid transfers heat between the steam storage tank and refrigerant, and thus the generator temperature increases. This design was intended as an alternate for a traditional 3.5 kW room air conditioner with substantially lower energy consumption. This modified system consumed lesser energy input of about 20-30% than conventional air conditioners. Further, for the same specification, the ejector system has consumed less power of about 2.475 kW than the traditional refrigeration system.
ABSTRACT
The objective of the work is to analyse and to improve the efficiency of solar-powered ejector refrigeration system integrated with flat-plate collector and Scheffler concentrator. The Scheffler concentrator of 2.7 m2 and flat-plate collector of 5 m2 collecting area are coupled with the storage tank of 15 l capacity. The developed system was designed for a potential replacement of conventional 1-ton room air conditioner with much reduced electrical energy consumption. The system was built based on two key subsystems namely 'Scheffler concentrator-based vapour system' and 'ejector-based cooling system'. The pilot effort showed promising results with the probability of energy-saving potential as near 70 to 80% over conventional air conditioners.
Subject(s)
Solar Energy , Electricity , RefrigerationABSTRACT
This work analyses the performance and emission characteristics of biofuelled compression ignition (C.I) engine with the implementation of an antioxidant. Using the transesterification process with sodium hydroxide as a catalyst, the beef tallow methyl ester (BTME) was obtained from the beef tallow oil. Poor physical properties of biodiesel (beef tallow oil (BTO)) namely high viscosity and density cause atomization problems leading to higher smoke, hydrocarbon and carbon monoxide emissions. The purpose of this work is to enhance the performance aspects, to limit smoke emissions from BTO operation and to examine the possibility of direct use of neat BTO in CI engine. This research paves a way of investing the impact of binary blends of BHA and BTO on the research engine. The experiments were conducted on a single-cylinder four-stroke C.I engine using the following fuel compositions: 20% of BTME mixed with 80% diesel (B20), 1000 ppm mono-phenolic antioxidant (butylated hydroxyanisole (BHA)) mixed with the blends of B20 (B20 + BHA), and 100% diesel. Based on the experimental results, it was found that the brake thermal efficiency (BTE) increases by 1.8% and the brake specific fuel consumption (BSFC) decreases by 2.5% for the fuel blend B20 + BHA when compared with that for B20 fuel blend. Compared with the B20 blend, the blend B20 + BHA emits 12.2% lesser nitrogen oxide due to breaking chain reactions, scavenging the initiating radicals and reducing the concentration of reactive radicals.
