Abstract—Corn is cultivated in most countries because of high consumption, quality, and food value. This study evaluated needed energy for cutting corn stems in different levels of cutting height and moisture content. For this reason, test device was fabricated and then calibrated. The device works on the principle of conservation of energy. The results were analyzed using split plot design and SAS software. The results showed that effect of height and moisture content and their interaction effect on cutting energy are significant (P<1%). The maximum cutting energy was 3.22 kJ in 63 (w.b.%) moisture content and the minimum cutting energy was 1.63 kJ in 83.25 (w.b.%) moisture content. Keywords—Cutting energy, Corn stalk, Cutting height, Moisture content, Impact cutting. I. INTRODUCTION ITH scientific name of Zea mays, corn is monoecious, annual plant. After rice and wheat, corn is the third important crop in the world and its importance is due to high yields and cultivability in vast areas of world [1]. The food quality of forage in crop is very high. Corn is a very delicious food for cattle. Green soilage of corn is harvested after picking tassel up. If corn is harvested in phase of milky kernel state, it will have high protein level, dry matter and nutrients. This crop is very momentous for dairy sector and animal food processing due to short growing period and high performance. It is predicted that demand for forage corn will increase until 2020 about 45 percent. Forage corn plays key role in supplying bestial protein in world and country for producing white and red meat. Needed mechanical energy was measured for chopping three types of product including corn, wheat straw and grass by a knife cutter. Total net energy at (kW m - 1 g -1 ) was considered as needed energy for cutting by cutter. The results of their experiments showed that total net energy increases with increased speed of shear knifes for grass, wheat straw and corn and consequently the sum of total energy and effective energy increase with decreasing grain size [2]. Researcher reported that cutting plant productions in smaller piece is an energy consuming process and needed energy is variable based on initial length of grain, moisture content, their mechanical and physical properties and feeding rate of machine [3]. Reference [4] conducted a study to determine the Mohsen Azadbakht is with the Department of Agricultural Machinery Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran (Corresponding author; Tel: +981714426942; e-mail: azadbakht@gau.ac.ir). Abbas Rezaei Asl and Karim Tamaskani Zahedi are with the Department of Agricultural Machinery Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran. effect of cut angle of sample based on cut quantities which it is possible to reduce cut energy in corn stem with moisture content of 15 to 20 (w.b.%). They concluded that the properties and features of earned shear force in corn stem vary with different directions. The maximum of failure force, stem cut and various nodes have significant relationship with cross- sectional area of stem. Total net energy amount from dry stem of corn is 23.5 to 11.3 kN/m. Shear energy is much less in parallel direction than perpendicular direction and shear energy and net energy is about one-tenth in parallel direction and about one-fifth for nodes. Researchers reported that rotary harvester machines are used increasingly in terms of ease in construction, low cost for repair and maintenance and ability to cut all stems with large and small diameters [5]. One of the most important factors in designing the types of grain combine and harvesters is resistance to cut in agricultural crops during harvesting [6]. So it is important to determine resistance to cut rate in canola plant. Cutting a stem by one edge device has difference with cutting a two edge device. Next, cutting is done by two elements with opposite action. The stem is kept constant in the vicinity of cut blade and then the blade does its work. Cutting with a single element can be largely affected by blade speed, product inertia and the sharpness of cutting edge. Leaning stem crop against knife pressure and preventing penetration to interior materials occurs to some extent. Cutting process depends on stem inertia for overcoming opposite force [7]. According to many researches, needed energy for the cut unit of stem in cutter bar consists of as follows: overcome on air friction, chopping of crops, overcome on the friction of chopped products, friction in some parts of machine and cutting stem [8]-[13]. Cutting energy in the stem of agricultural crops shows that how much energy is needed for cutting stems in agricultural crops. Harvesting machines and harvesters should be redesigned for lowering energy consumption [14]. Expressions for determining cutting energy requirement and peripheral knife speed for other crops were given as stated by [15]-[17], [2]. Researchers reported that needed energy for cutting wheat stem is affected moisture content, type of wheat, blade angle and cutting speed [18]. With decreasing moisture content and blade angle and increasing cutting speed, cutting energy will decrease. The effect of variety on cutting energy is remarkable. In terms of product type and physical and mechanical properties of stem in crops, the estimation of harvesting energy in agricultural products can be completely different [17]. The aim of this study is to survey needed energy for cutting corn stalks in different levels of height and moisture content. M. Azadbakht, A. Rezaei Asl, K. Tamaskani Zahedi Energy Requirement for Cutting Corn Stalks (Single Cross 704 Var.) W World Academy of Science, Engineering and Technology International Journal of Biological, Biomolecular, Agricultural, Food and Biotechnological Engineering Vol:8, No:5, 2014 479 International Scholarly and Scientific Research & Innovation 8(5) 2014 scholar.waset.org/1999.1/9998237 International Science Index, Agricultural and Biosystems Engineering Vol:8, No:5, 2014 waset.org/Publication/9998237