Advanced SearchSearch Tips
Straw to Grain Ratio Equation for Combine Simulation
facebook(new window)  Pirnt(new window) E-mail(new window) Excel Download
  • Journal title : Journal of Biosystems Engineering
  • Volume 40, Issue 4,  2015, pp.314-319
  • Publisher : Korean Society for Agricultural Machinery
  • DOI : 10.5307/JBE.2015.40.4.314
 Title & Authors
Straw to Grain Ratio Equation for Combine Simulation
Kim, Sang Hun; Gregory, James M.;
  PDF(new window)
Purpose: The ratio of straw to grain mass as a function of cutting height affects combine efficiency and power consumption and is an important input parameter to combine simulation models. An equation was developed to predict straw to grain ratios for wheat as a function of cutting height. Methods: Two mass functions, one for straw and one for grain, were developed using regression techniques and measured data collected in west Texas during the summer, and used to predict the straw to grain ratio. Results: Three equations were developed to facilitate the simulation of a combine during wheat harvest. Two mass functions, one for straw and one for grain, were also developed; a quadratic equation describes the straw mass with an of 0.992. An S-shaped curve describes the mass function for grain with an of 0.957. An equation for straw to grain ratio of wheat was developed as a function of cutting height. The straw to grain ratio has an value of 0.947. Conclusions: In all cases, the equations had values above 0.94 and were significant at the 99.9 percent probability level (alpha = 0.001). Although all three equations are useful, the grain mass and straw to grain ratio equations will have direct application in combine simulation models.
Combines;Harvesting;Simulation;Straw to grain ratio;Cutting heights;
 Cited by
Arnold, R. E. and J. R. Lake. 1964. Experiments with Rasp Bar Threshing Drums. III : Power Requirement. Journal of Agricultural Engineering Research 9:348-355.

Douglas, C. L., Jr., P. E. Rasmussen and R. R. Allmaras. 1989. Cutting Height, Yield, Level, and Equipment Modification Effects on Residue Distribution by Combine. Transactions of the ASAE 32(4):1256-1262.

Gregory, J. M. and C. B. Fedler. 1986. Model Evaluation and Research Verification (MERV). ASAE paper no. 86-5032.

Gregory, J. M. and C. B. Fedler. 1987. Mathematical Relationship Prediction Grain Separation in Combines. Transactions of the ASAE 30(6):1600-1604. crossref(new window)

Quick, G. R. and W. F. Buchele. 1978. The Grain Harvesters. ASAE.

Raheja, S. K., P. C. Mehrotra and D. L. Ahuja. 1983. A Methodological Study on Estimation of Straw to Grain Ratio in Wheat Crop. Journal of the Indian Society of Agricultural Statistics 35(2):79-8.