LOW CYCLE FATIGUE LIFE ESTIMATION OF A TURBINE BLISK

This paper deals with low cycle life estimation of a turbine blisk. The turbine blisk operates at extreme conditions; hence it is subjected to aerodynamic loads and high centrifugal loads. The loads on the turbine blisk vary due to the mission profile of the vehicle that includes takeoff, cruise and landing. An elastic-plastic finite element analysis is carried out. The life at the obtained stress and strain values is estimated using nCode DesignLife tool. Strain life approach is followed to estimate the life and Smith Watson Topper's approach is followed to carry out the mean stress correction.This paper deals with low cycle life estimation of a turbine blisk. The turbine blisk operates at extreme conditions; hence it is subjected to aerodynamic loads and high centrifugal loads. The loads on the turbine blisk vary due to the mission profile of the vehicle that includes takeoff, cruise and landing. An elastic-plastic finite element analysis is carried out. The life at the obtained stress and strain values is estimated using nCode DesignLife tool. Strain life approach is followed to estimate the life and Smith Watson Topper's approach is followed to carry out the mean stress correction

Recent Advances in Pigeonpea [Cajanus cajan (l.) Millspaugh) Research

Pigeonpea or red gram [Cajanus cajan (L.) Millspaugh] is an important food legume of the semi-arid tropics of Asia and Africa. It occupies a prime niche in sustainable farming systems of smallholder rainfed farmers. It occupies a prominent place in Indian rainfed agriculture. It is an integral component in various agro ecologies of the country mainly inter cropped with cereals, pulses, oilseeds and millets. It is the second most important pulse crop next to chickpea, covering an area of around 4.42 m ha (occupying about 14.5% of area under pulses) and production of 2.86 MT (contributing to 16% of total pulse production) and productivity of about 707 kg/ha. It is mainly consumed as dry split dhal throughout the country besides several other uses of various parts of pigeonpea plant. Enhancing the productivity of the crop assumes specific significance in India mainly to combat protein malnutrition as it is the main source of protein to the predominant vegetarian population. The productivity of pigeonpea has remained low and stagnant over the last few decades thus this prompted scientists to search for novel ways of crop improvement. To tackle this challenge, ICRISAT and IIPR are working on number of innovative ideas like, genome sequencing (Varshney et al. 2012), development of CGMS hybrids with 30 to 40 % yield advantage over traditional varieties, development of photo insensitive super early maturing lines, introgression of cleistogamous flower structure to maintain genetic purity of elite lines, use of obcordate leaf shape as NEP to assess genetic purity of hybrid parental lines and development of disease resistant hybrids and elite breeding lines. These aspects are described briefly below

Strategies for pigeonpea improvement

In order to feed an ever-increasing population, it is essential to deal yield reducing factors. Climate smart crop varieties that yield more with fewer inputs will be required to achieve the success. In this scenario pigeonpea plays an important role as it can stand in relatively harsh environmental conditions. Hybrid breeding along with the pure line breeding, genetic resources and genomics advances are enriching this crop. However, the pigeonpea improvement program must be re-oriented in order to deal with the yield-reducing factors and to break the yield plateau

Technologies for Intensification of Production and Uses of Grain Legumes for Nutrition Security

Malnutrition resulting from intake of food poor in nutritional value, particularly lacking in micronutrients, has been recognized as a serious health problem in developing countries including India. Nutritional security is a priority for India. Crop diversification in agriculture contributes to balanced diet and nutritional security. Production intensification of nutrient-dense crops, contributes to their increased production, and consequently enhances their accessibility at affordable prices to meet nutritional security. Grain legumes produce nutrient-dense grains rich in proteins, vitamins, minerals and micronutrients essential for growth and development. However, cultivation of grain legumes is often neglected resulting in poor production in the country, and consequently poor access to legumes at affordable prices. Pigeonpea or red gram (Cajanus cajan L.), chickpea or bengal gram (Cicer arietinum L.) and groundnut (Arachis hypogaea L.), the three nutritious grain legumes are grown widely across the country and are major constituents of Indian diets. They are climate- resilient crops adapted to water-limiting conditions making them choice crops for cultivation in adverse conditions. Policy options for promoting cultivation and increased production of pigeon pea, chickpea and groundnut are needed. Technology options for intensification of their cultivation include improved cultivars of grain legumes with enhanced adaptation and nutritional properties, their processing, plugging post-harvest and storage losses, and development of alternative food products. The chapter discusses the contribution of agriculture to nutritional security and the need to diversify cultivation of crops to include nutrient-dense grain legumes, and intensification of their cultivation to achieve their enhanced production and productivity. The scope to develop bio-fortified grain legumes is also discussed. Some countries have successfully harnessed the potential of processed grain legumes for use as food supplements for children and elderly, as well as to prepare ready-to-use-therapeutic-food products to treat acute malnutrition

Review on unexplored Asava Arishthas of Gada Nighraha

Gada Nigraha is very well known ancient text of Ayurveda. It acquaints us with many indispensable formulations. Many of these formulations are unfathomed. Eminently many Asava Arishtas mentioned by Acharya are very unique in their method of preparation like Gugguluvasava, Tambulasava, Kushmandasava, Gandikadronasava, Narikelasava etc. here an effort is made to accentuate these formulations with intention of carrying further exploration in this regard

Pigeonpea seed systems in Asia

Pigeonpea seed systems consist of the formal and informal seed sector. However, the informal seed sector dominates the seed production system. Majority of rainfed farmers who grow pigeonpea (about 80% - 90%) save a part of their produce as seed requirement. In the formal seed sector, government agencies and private companies are involved in production and distribution of quality seeds of improved varieties and hybrids. Role of private sector diffusion in pigeonpea market is not encouraging owing to lack of commercial perspective in the crop and other factors. The integrated approach that takes into cognizance the formal and informal seed sector in breeding, seed production and distribution has shown to have promising potential for improving seed supply to smallholder farmers. Moreover, any seed system, for that matter, requires a regulatory framework as well as a seed policy that considers regulations of an expanding and diversifying seed sector for the benefit of the farmers engaged in the seed production system

Pigeonpea perspective in India

Pigeonpea occupies a prominent place in Indian rainfed agriculture. It is an integral component of in various agro ecologies of the country mainly inter cropped with cereals, pulses and oilseeds and millets. It is the second most important pulse crop next to chickpea, covering an area of around 4.42 m ha (occupying about 14.5% of area under pulses) and production of 2.86 MT (contributing to 16% of total pulse production) and productivity of about 707 kg/ha. It is mainly consumed as dry split dhal throughout the country besides several other uses of various parts of pigeonpea plant. Enhancing the productivity of the crop assumes specific significance in India mainly to combat protein malnutrition as it is the main source of protein to the predominant vegetarian population. Based on the crop duration and climatic condition the crop is grouped under four agro ecological zones with varied plant type requirements and location specific constraints for each zone. Systematic crop improvement efforts were launched at ICRSIAT since its inception in 1972. It focused during first decade (1972 to 1980) on collection, evaluation, maintenance and sharing of germplasm and yield enhancement research. During 1980 to 2000 ICRISAT research priorities were development of stable sources of resistance for wilt and Sterility Mosaic Diseases which are highly devastating and endemic in India in almost all the agro ecologies of pigeonpea cultivation. From 2000, concerted efforts are in progress on CGMS based hybrid development. Spectacular achievement by ICRISAT in recent past in the crop is deciphering its genome sequence and it has ushered pigeonpea in to genomic era. Subsequently lot of genomic information is in the process of development through molecular approaches like Genome Wide Association Studies (GWAS), Nested Association Mapping (NAM). Multiparent Advance Generation Inter Crosses (MAGIC) and Introgression Libraries (IL) etc. These approaches are under process of utilization for crop improvement

Pigeonpea - A unique jewel in rainfed cropping systems

Pigeonpea is a crop for rainfed environments endowed with several features to thrive harsh climate. It adapts well in sole crop and inter cropped conditions (with cereals, millets, oils seeds and pulses) by enhancing the system productivity and net income to the small and marginal farmers across the globe. The range of maturity duration in the crop allows it to grow in diversified cropping systems and patterns in varied ecoregions of the world. Development of cytoplasmic male sterility based hybrids provided an opportunity for enhancing the yields under marginal environments. With recent interventions in addressing the photo sensitivity and maturity have led to evolving super early varieties with less than 100 days duration, provided a scope for horizontal expansion of the crop in different agro ecological systems

Ultrasound bone mineral density of Os Calcis - its relationship with bone mineral markers and 25(OH) vitamin D in endemic fluorotic and non-fluorotic villages

Objectives: To study the relationship between the nutritional status, serum bone mineral markers, 25 hydroxy vitamin D [25(OH)D] levels and ultrasound bone mineral density (USBMD) of Os Calcis in subjects living in endemic fluorotic and non-fluorotic villages. Methods: Subjects from fluorotic (n=57) and non-fluorotic (n=79) villages were studied for their dietary habits, biochemical parameters of bone mineral markers, 25(OH)D levels and correlated with stiffness index (SI) measured using Achilles ultrasound bone densitometer. Results: Dietary calcium intake in both the villages is far below the recommended daily allowances (RDA) by Indian Council of Medical Research (ICMR), India for Indian population. The 25(OH)D correlated positively with energy intake (r=0.7; p<0.001); dietary calcium (r= 0.5; p<0.001); and negatively with phytate/calcium ratio (r=0.2; p<0.001), in subjects in fluorotic villages. No similar correlation was observed among subjects from non-fluorotic villages. For comparable levels of serum calcium, subjects in non-fluorotic villages were more osteopenic than the fluorotic counterparts. USBMD did not correlate with 25(OH)D in the fluorotic and non-fluorotic subjects. Conclusions: The dietary calcium intake among subjects from fluorotic and non-fluorotic villages is less than the RDA suggested by ICMR. The 25(OH)D levels of both these villages were in the vitamin D insufficiency range. USBMD does not correlate with the 25(OH)D status of an individual and it should not be used for screening osteoporosis in areas endemic for fluorosis