The Experts below are selected from a list of 102 Experts worldwide ranked by ideXlab platform
John Campbell - One of the best experts on this subject based on the ideXlab platform.
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Mass and heat transfer during feeding of castings
International Journal of Cast Metals Research, 2002Co-Authors: Murat Tiryakioğlu, Ergin Tiryakioğlu, John CampbellAbstract:Abstract Feeder models that incorporate mass transfer from feeder to casting are reviewed, and assumptions made during their development are discussed. A new approach that incorporates a superheat model from the literature is introduced. The new approach is based on the equality of solidification times of feeder and the feeder-casting combination. The superheat model is used to adjust the solidification times of feeder and casting to account for heat transfer. Introduction One of the biggest contributions to foundry engineering was made by Chvorinov, 1 who stated that the solidification time, t , is determined by: n AVt B (1) where B is the mould constant, V is the casting volume, A is the surface area through which heat is lost, and n is a constant (2 in Chvorinov‟s work). Equation 1 is referred to as Chvorinov‟s Rule. The V/A ratio is known as the modulus (M), and has been used as the basis for a number of approaches to determining the size of feeders for the production of sound castings. Despite its wide acceptance, Chvorinov‟s Rule has certain limitations because of the underlying assumptions used in deriving the equation. As a result of these limitations, the exponent, n, fluctuates between 1 and 2, depending on the shape and size of the casting, and the mould and pouring conditions. One of the reasons for this anomaly is that Chvorinov‟s Rule originally did not take the shape of the casting into consideration. A new geometry-based model was introduced in an earlier publication
Murat Tiryakioğlu - One of the best experts on this subject based on the ideXlab platform.
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Mass and heat transfer during feeding of castings
International Journal of Cast Metals Research, 2002Co-Authors: Murat Tiryakioğlu, Ergin Tiryakioğlu, John CampbellAbstract:Abstract Feeder models that incorporate mass transfer from feeder to casting are reviewed, and assumptions made during their development are discussed. A new approach that incorporates a superheat model from the literature is introduced. The new approach is based on the equality of solidification times of feeder and the feeder-casting combination. The superheat model is used to adjust the solidification times of feeder and casting to account for heat transfer. Introduction One of the biggest contributions to foundry engineering was made by Chvorinov, 1 who stated that the solidification time, t , is determined by: n AVt B (1) where B is the mould constant, V is the casting volume, A is the surface area through which heat is lost, and n is a constant (2 in Chvorinov‟s work). Equation 1 is referred to as Chvorinov‟s Rule. The V/A ratio is known as the modulus (M), and has been used as the basis for a number of approaches to determining the size of feeders for the production of sound castings. Despite its wide acceptance, Chvorinov‟s Rule has certain limitations because of the underlying assumptions used in deriving the equation. As a result of these limitations, the exponent, n, fluctuates between 1 and 2, depending on the shape and size of the casting, and the mould and pouring conditions. One of the reasons for this anomaly is that Chvorinov‟s Rule originally did not take the shape of the casting into consideration. A new geometry-based model was introduced in an earlier publication
Ergin Tiryakioğlu - One of the best experts on this subject based on the ideXlab platform.
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Mass and heat transfer during feeding of castings
International Journal of Cast Metals Research, 2002Co-Authors: Murat Tiryakioğlu, Ergin Tiryakioğlu, John CampbellAbstract:Abstract Feeder models that incorporate mass transfer from feeder to casting are reviewed, and assumptions made during their development are discussed. A new approach that incorporates a superheat model from the literature is introduced. The new approach is based on the equality of solidification times of feeder and the feeder-casting combination. The superheat model is used to adjust the solidification times of feeder and casting to account for heat transfer. Introduction One of the biggest contributions to foundry engineering was made by Chvorinov, 1 who stated that the solidification time, t , is determined by: n AVt B (1) where B is the mould constant, V is the casting volume, A is the surface area through which heat is lost, and n is a constant (2 in Chvorinov‟s work). Equation 1 is referred to as Chvorinov‟s Rule. The V/A ratio is known as the modulus (M), and has been used as the basis for a number of approaches to determining the size of feeders for the production of sound castings. Despite its wide acceptance, Chvorinov‟s Rule has certain limitations because of the underlying assumptions used in deriving the equation. As a result of these limitations, the exponent, n, fluctuates between 1 and 2, depending on the shape and size of the casting, and the mould and pouring conditions. One of the reasons for this anomaly is that Chvorinov‟s Rule originally did not take the shape of the casting into consideration. A new geometry-based model was introduced in an earlier publication
Li Si-nian - One of the best experts on this subject based on the ideXlab platform.
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Calculating Methods of Cast Steel Risers' Minimum Safety Height and Volume Ratio of Surplus Molten Steel
2008Co-Authors: Li Si-nianAbstract:The calculating formulas about the risers' minimum safety height and the volume ratio of the surplus molten steel were derived by establishing the solidification mathematical model of a riser-casting system and using the Chvorinov law involving the relationship between freezing time of liquid steel and its geometric modules.When the cast steel risers were designed by modules or other methods,the parameters derived from the above formulas could be used as safety check.The practice indicated that the shrinkages in risers could not embed in the castings while the minimum safety height was 25% thicker than the wall thickness or heat node circle diameter of castings and the risers' volume ratio of the surplus molten steel was higher than 15%.Based on this,the riser efficiency would be not limited and the casting yield outstandingly raised.
Daniel Molnar - One of the best experts on this subject based on the ideXlab platform.
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Control Volume Simulation of Casting Directional Solidification
Materials Science Forum, 2014Co-Authors: Imre Budavari, Daniel MolnarAbstract:Quality demands of castings is elemental in recent years and becoming more stringent. Foundries are faced by the need to produce high quality castings, but nonetheless to produce them economically. To fulfill this demand, experimental castings, especially in case of individual production or small runs, are uneconomical. In these cases computer simulation can be the only economical tool for testing and approval. The modulus technique of Chvorinov is an applicable method to examine the local solidification process and to determine the application of chills, geometry modification and feeding. Numerically the control volume method is used to check the solidification process of large steel castings with non-uniform wall thicknesses.