In the present work a three-dimensional model has been developed to study shielding gas flow and heat transfer in a laser welding process using computational fluid dynamics. This investigation was motivated by problems met while using an optical system to track the weld path. The aim of this study was to investigate if the shielding gas flow could disturb the observation area of the optical sys...

This paper addresses the differences in thermal characterization and modeling for a multi-chip package with respect to a single-chip package. Since no thermal measurement system is commercially available to power more than one device during the test, the thermal model can be validated only with a single-heat source. Wires, which are used to connect the package under the test to the measurement ...

An instrument designed to measure thermal conductivity of consolidated rocks, dry or saturated, using a transient method is presented. The instrument measures relative values of the thermal conductivity, and it needs calibration to obtain absolute values. The device can be used as heat pulse line source and as continuous heat line source. Two parameters to determine thermal conductivity are pro...

The inverse modeling of heat transfer involves the estimation of boundary conditions from the knowledge of thermal history inside a heat conducting body. Inverse analysis is extremely useful in modeling of contact heat transfer at interfaces of engineering surfaces during materials processing. In the present work, the one-dimensional transient heat conduction equation was inversely modeled in b...

In the present paper, an axisymmetric two-dimensional model for powder mixed electric discharge machining (PMEDM) has been developed using the finite element method (FEM). The model utilizes the several important aspects such as temperaturesensitive material properties, shape and size of heat source (Gaussian heat distribution), percentage distribution of heat among tool, workpiece and dielectr...

basic understanding of the process of coolant heat transfer inside an engine is an indispensable prerequisite to devise an infallible cooling strategy. coolant flow and its heat transfer affect the cooling efficiency, thermal load of heated components, and thermal efficiency of a diesel engine. an efficient approach to studying cooling system for diesel engine is a 3d computational fluid dynami...

A multi-functional heat-pump system is proposed to efficiently utilize the gray water as heat source and sink for heating and cooling of residential buildings, respectively. Heat is reclaimed from the plate heat exchanger installed at the outlet of the compressor to provide sufficient hot water for residential use. To study the performance of this innovative system, laboratory testing is perfor...

This paper describes a simplified system model for rapidly evaluating disturbance propagation through a heat exchanger network. The model depicts cause-effect relationships between a set of stream output variables (target temperature fluctuations) and a set of input variables (disturbances of source temperatures and heat capacity flowrates). The model, which consists of a set of linear equation...

The design of a four-bed three-stage adsorption cycle has been proposed to reduce the volume of the six-bed three-stage adsorption cycle. A simulation model for the proposed innovative cycle was developed to analyse the influence of cycle time on the system performance identifying the specific cooling power (SCP) and coefficient of performance (COP). A particle swarm optimization (PSO) techniqu...