This paper presents finite element analysis (FEA) of a coated and uncoated cylinder heads of a diesel engine to examine the distribution of temperature and stress. A thermal barrier coating system was applied on the combustion chamber of the cylinder heads, consists of two-layer systems: a ceramic top coat (TC), made of yttria stabilized zirconia (YSZ), ZrO2-8%Y2O3 and also a metallic bond coat...

The purpose of this paper is to give an elementary proof of the fact that a Banach space in which there exist projection transformations of norm one on every two-dimensional linear subspace is a euclidean space. S. Kakutani [ l ] has pointed out that a modification of a proof due to Blaschke [2] will prove this theorem. F. Bohnenblust has been able to establish this theorem for the complex case...

This study presents effects of the vane spring stiffness on frictional power characteristics of a refrigeration compressor. Comparisons on the compressor performance are investigated for different vane spring stiffnesses with compressors designed with high and low shell pressures. Results show that while compressors with a low shell pressure using a higher spring stiffness combination may reduc...

Let D be a negative discriminant, and let Θ(D) be the complex vector space generated by the binary theta series θf attached to the positive definite binary quadratic forms f(x, y) = ax + bxy + cy whose discriminant D(f) = b − 4ac equals D/t, for some integer t. It is a well-known classical fact that Θ(D) is a subspace of the space M1(|D|, ψD) of modular forms of weight 1, level |D| and Nebentyp...

is a (nonconstant) arithmetic progression of positive integers. We consider a general binary quadratic form ax2 + bxy + cy' ( a , b , c E Z ) and ask the question "Can the form ax' + hxy + ry' represen1 every inleger in 1he arithmetic progression kNo + 1 for any natural numbers k and l?" In a sampling of books containing a discussion of binary quadratic forms [2]-[9], we did not find this qustl...

The pursuit of increasing the efficiency internal combustion engines is an ongoing engineering task that requires numerous research efforts. New concepts injection or systems require preliminary investigation work using engines. These engines, usually single-cylinder, make it possible to isolate a single variable in complex mixture preparation process, thus enabling analysis changes being made....

Porous media has interesting features in compared with free flame combustion due to the extended of the lean flammability limits and lower emissions. Advanced new generation of internal combustion (IC) engines are expected to have far better emissions levels both gaseous and particulate matter, at the same time having far lower fuel consumption on a wide range of operating condition. These c...