To produce casting with efficient use of material, energy, lead time and manpower is very essential to sustain in foundry industry. Mould with dense cast cavities or less number of cavities may lead to more solidification time, poor mechanical properties and defects like shrinkage, misrun and cold shut. It is proposed to design mould layout with selection of suitable combination of mould size and multiple number of cavities based on temperature distribution and solidification time which results in optimization of casting yield.Casting simulations are carried out for casting mould with single cavity based on mould size and variation of cavity –wall distance for Al-alloy component in green sand mould result in finding of minimum cavity wall gap. Double and multiple cavities moulds are simulated based on cavity-wall distance value and variation of cavity-cavity distance along with temperature distribution, solidification time and defects if any in cast part results in computing minimum cavity-cavity distance. Applying this in mould layout design, it leads into optimum mould layout and casting yield. AutoCAST-X1 simulation results are validated by experimentation for LM4 alloy cast in sand mould allocated with thermocouples and data acquisition system.