LIVELIHOOD ANALYSIS OF SMALLHOLDER IRRIGATION FARMERS IN NIGERIA

The study assessed the smallholder irrigation farmers’ welfare by examining their irrigation practices and factor affecting their production outputs in Nigeria. Cross sectional survey was conducted and primary data were collected from 198 smallholder farmers across selected three major agro-ecological zones using a multistage sampling technique. The results revealed thatthe highest proportion of farmers using motor pump with groundwater (71%) and surface water (62%) irrigation system for farming live in houses made of cement and bricks compared to 59.1% for farmers who practice rainfed agriculture. About 81.5% of the tube wells are found among the motor pump irrigators, 30% respondents have hand dug wells. The percentage of farmers with motor pump and associated piping accessories ranges from 30% among gravity flow irrigators to 70% and 80% among surface and groundwater irrigators respectively. The analysis of factors affecting farmers productivity suggest that in order to increase productivity, the manual pump users, should be discouraged from excessiveuse of fertilizer and  large farm size while access to other inputs such as agrochemicals, education, association with social groups, capital formation should be strengthened. The motor pump users require large farm size to further increase their output level, while the gravity flow irrigators need to join farmers association. Furthermore, extension services across the agro-ecological zones should be resuscitated in order to increase agricultural productivity.Â

Experimental investigation of overall cooling effectiveness on combustion chamber liner with and without impingement holes

The gas turbine combustor liner which is subjected to high temperature requires efficient cooling. In earlier days concept of slot film cooling is utilized in the combustion liners and in modern combustors multiple row film cooling (effusion cooling) is mainly used. This study aims at the experimental investigation of overall film cooling effectiveness of an effusion plate with and without impingement holes at the backside. The experiments are done at different blowing ratios and the surface temperature measurements are taken using infrared thermography. The effusion and impingement holes are arranged in staggered manner on two parallel plates and each effusion hole is surrounded by four impingement holes. Effusion holes are drilled at an angle of 27° and the impingement plate is kept at a distance of 6D away from the effusion plate. The experiments are done on the effusion plate with and without impingement plate at the backside. The results show, increase in cooling effectiveness as the blowing ratio increases. The comparative results shows that at a particular blowing ratio the overall cooling effectiveness is higher for effusion plate with impingement holes at the backside due to the higher convective heat transfer coefficients produced by the impinging jets at the cold side of the effusion plate