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Cylinder head design is one of the most involved disciplines in engine design. Whether designing an altogether new head or revamping an old one, several different coupled and inter-dependent technologies ranging from heat transfer, fluid flow, combustion, material non-linearity, structural and fatigue have to be accounted. Simultaneous designing of ports, jacket and combustion chamber leads to cylinder head design, which is then tested for its strength and durability. Traditionally a series of analytical, empirical, test-based and simulation based exercises are conducted to design cylinder heads. With increasing pressure on reducing cost and turnaround time, focus on moving towards a quasi-simulation based design and development of cylinder heads is gaining strength. This paper talks about how a simulation driven process for cylinder head design can be developed.

CFD simulations of an engine cooling system needs to resolve two aspects of the system; in-cylinder combustion and engine cooling. Underlying physics of an in-cylinder combustion process and heat transfer through engine cooling system requires very different time scales for resolution. This puts a limitation on practicality of solving the two problems simultaneously for any industrial case. Instead of solving the problem simultaneously, solution for an engine cooling system operating at a constant load can be derived using the coupled approach. This involves running two different CFD simulations: a transient in-cylinder simulation to model combustion in the engine, and a steady state CHT simulation using engine cooling system for heat transfer. These simulations are thermally coupled through boundary conditions and are performed in cyclic manner one after the other. Simulations are continued till the change in temperature with coupled cycles becomes insignificant.

Dual fuel operating strategy offers great opportunity to reduce emissions like particulate matter and NOx from compression ignition engine and use of clearer fuels like natural gas. Dual-fuel engines have number of potential advantages like fuel flexibility, lower emissions, higher compression ratio, better efficiency and easy conversion of existing diesel engines without major hardware modifications. In view of energy depletion and environmental pollution, dual-fuel technology has caught attention of researchers. It is an ecological and efficient combustion technology. This paper summarizes a review of recent research on dual-fuel technology and future scope of research. Paper also throws light on present limitations and drawbacks of dual-fuel engines and proposed methods to overcome these drawbacks. A parametric study of different engine-operating variables affecting performance of diesel-CNG dual-fuel engines vis-à-vis base diesel operation is also summarized here.

To-date the primary challenge in conducting aerodynamic CFD simulations of actual vehicles with realistically complex geometry has been the construction of a computational mesh. The CAD-to-Mesh processes used to-date have been laborious, often requiring many weeks of engineering time. In this paper we present a new technique to greatly expedite the CAD-to-Mesh process. The fundamentals of this technique are discussed followed by case studies that show that this technique can reduce the engineering time required for the CAD-to-Mesh process to just a few hours.

Computational Fluid Dynamics simulation of aero-acoustics requires a high fidelity mesh. For Direct simulations, a very good quality and reasonably refined mesh is required in the entire domain encompassing the source and receiver of the sound. A usual practice so far has been to use structured grid to mesh the geometries. For complex geometrical shapes, such as throttle body, creating a fully structured mesh becomes very tedious and could consume a lot of time. Once the computational model is in place, obtaining meaningful solution also takes a long time since the solution has to be run for quite the long time in order to capture reasonably accurate sound pressure data. The current paper focuses on both of these time-consuming aspects. A comparative study of three different mesh types in a throttle body geometry is considered.