Thermal Engineering

Environmental and Economic Assessment of a Greenhouse Waste Heat Exchange

by Joshua Pearce

R. Andrews and J.M. Pearce, “Environmental and Economic Assessment of a Greenhouse Waste Heat Exchange”, Journal of Cleaner Production 19, pp. 1446-1454 (2011)

As the economic costs of energy and the negative externalities associated with the combustion of fossil fuels threaten... more As the economic costs of energy and the negative externalities associated with the combustion of fossil fuels threaten the economic viability of greenhouses in northern climates there is a renewed interest in the use of waste heat. This paper presents a technical and economic methodology to determine the viability of establishing waste heat greenhouses using the waste heat from industrial processes in northern climates. A case study is presented of an exchange between a tomato greenhouse and a flat glass manufacturing plant, which found the waste heat system is significantly more economic to operate than a purely natural gas system.

Changes of Skin Temperature of Parts of the Body and Serum Asymmetric Dimethylarginine (ADMA) in Type-2 Diabetes Mellitus Indian Patients

by Anburajan Mariamichael

33rd Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS), Boston, Massachusetts USA, August 30 - September 3, 2011

In India, number of people with type 2 Diabetes Mellitus (DM) would be 87 million by the year 2030. DM disturbs... more In India, number of people with type 2 Diabetes Mellitus (DM) would be 87 million by the year 2030. DM disturbs autonomic regulation of skin microcirculation, and causes decrease in resting blood flows through the skin. The skin blood flow has a major effect on its temperature. The aim of the study was to evaluate changes of skin temperature of all parts of the body and serum asymmetric dimethylarginine, ADMA (μmol/L) in type-2 DM Indian patients. Group-I: Normal (n=17; M/F: 10/15, mean±SD= 43.2±9.4 years); Group-II: Type-2 DM without cardiovascular (CV) complications (n=15; M/F: 10/7, mean±SD= 46.3 ± 14.0 years); Thermograms of all parts of the body were acquired using a non-contact infrared (IR) thermography camera (ThermaCAM T400, FLIR Systems, Sweden). Blood parameters and thyroid hormone were measured biochemically. Indian diabetic risk score (IDRS) was calculated for each subject. In type-2 DM patients without CV group (n=15), there was a statistically significant (p=0.01) negative correlations between HbA1c and skin temperature of eye and nose (r= -0.57 and r= -0.55 respectively). ADMA was correlated significantly (p=0.01) with HbA1c (r=0.65) and estimated average glucose, eAG (r=0.63). In normal subjects, mean minimum and maximum values of skin temperatures were observed at posterior side of sole (26.89°C) and ear (36.85°C) respectively. In type-2 DM without CV, mean values of skin temperature in different parts of the body from head to toe were lesser than those values in control group; but this decreases were statistically significant in nose (32.66 Vs 33.99°C, p=0.024) as well as in tibia (32.78 Vs 33.13°C, p=0.036) regions.

Dynamic Thermal-Mechanical-Electrical Modeling of the Integrated Power System of a Notional All-Electric Naval Surface Ship

by Christopher Holsonback

Masters Thesis

The goal of this thesis is to develop a dynamic, thermal-mechanical-electrical model of the integrated power system... more The goal of this thesis is to develop a dynamic, thermal-mechanical-electrical model of the integrated power system (IPS) of a notional all-electric ship. This model will serve as a baseline for future testing of novel thermal management technologies and
architectures to identify tradeoffs, improve system-level efficiency, and increase the capabilities of the ship. The IPS modeled in this work is based on the DDG 1000, including gas turbine engines, synchronous generators, a simple electrical distribution
system, motor converters, propulsion motors, fixed-pitch propellers, and a ship hull.

First, an initial estimate is made of the waste heat generated by components of the IPS at a variety of steady state ship speeds using known component power range and efficiency characteristics. Generator scheduling is utilized to minimize fuel consumption.This initial waste heat estimation serves as a reference for the dynamic modeling that follows.

Next, the techniques and assumptions used to develop dynamic models of the IPS components are presented in depth. Each model typically evolves from an initial steady state version to a dynamic version through several iterations, and the dynamic response is validated based on data available in the literature.

Finally, the IPS component models are integrated into a single model and dynamic results for two ship-maneuvering scenarios are presented. Interesting thermal-mechanical-electrical dynamics are discussed in depth. Comparison is made to the initial waste heat estimation, and the agreement is found to be excellent. Crashback results are compared to data from the literature, and reasonable agreement is found. Conclusions
drawn from the development of the IPS model are presented, as are recommendations for future work that build on this baseline system.

Ion beam oxidation of GaAs: The role of ion energy

by Nicole Herbots

O. Vancauwenberghe, N. Herbots. H. Manoharan,a) and M. Ahrens

Massachusetts Institute of Technology, Cambridge,
Maassachusetts 02139

J. Vac. Sci. Technot A 9 (3), May/Jun 1991, pp. 1035-1039

In this work, room temperature oxidation of GaAs was investigated using ion beam oxidation (mO). In lBO, an ion beam... more In this work, room temperature oxidation of GaAs was investigated using ion beam oxidation (mO). In lBO, an ion beam is used to introduce oxygen athermally into the substrate, in this case GaAs. GaAs bonds are broken upon collision with the ions, making gallium and arsenic atoms readily available to react with the oxygen species. Ion beam oxidation of GaAs at room temperature was studied as a function ofoxygen ion energy between 500 and is keY. The ion beam oxidized GaAs was characterized in situ by Auger electron spectroscopy (AES) and ex situ with x-ray photoelectron spectroscopy (XPS) for accurate determination of the film chemical composition. Below 1 keY, a thin oxide film is formed: it is composed of Ga20 3 and AS20 3 with almost no metallic arsenic, and presents insulating properties.
As the ion energy increases, preferential sputtering of As and decomposition of AS203 increase and prevent formation of an
insulating film. No damage was detected by Rutherford backscattering spectrometry (RES) combined with ion channeling, in the substrate subjected to IBO below 1 keV.

Inverse solution of radiative heat transfer in two-dimensional irregularly shaped enclosures

by hakan erturk

The use of inverse methods for the design and control of radiant sources

by hakan erturk

The Use of Inverse Formulation in Design and Control of Transient Radiant Systems

by hakan erturk

Boundary condition design to heat a moving object at uniform transient temperature using inverse formulation

by hakan erturk

Efficient Signal Transport Model for Remote Thermometry in Full-Scale Thermal Processing Systems

by hakan erturk

Thermal devices integrated with thermoelectric modules with applications to CPU cooling

by hakan erturk

Thermal performance and key challenges for future CPU cooling technologies

by hakan erturk

Accuracy of Monte Carlo Method Re-Examined on a Box-Shaped Furnace Problem

by hakan erturk

Inverse design methods for high-temperature systems.

by hakan erturk

Evaluation of image reconstruction algorithms for non-destructive characterization of thermal interfaces

by hakan erturk

Thermal performance of thermoelectric cooler (tec) integrated heat sink and optimizing structure for low acoustic noise/power consumption

by hakan erturk

Validation of inverse boundary condition design in a thermometry test bed

by hakan erturk

The Use of Inverse Methods for the Design and Control of Radiant Sources

by hakan erturk

Reduced-Order Models for the Calculation of Thermal Transients of Heat Conduction/Convection FE Models

by Stefano Zucca

Scanning probe microscopy generated out-of-plane deformation maps exhibiting heterogeneous nanoscale deformation resulting from thermal cycling of Cu- …

by Nazri Kamsah

Journal of Materials Research, Volume 16, Issue 12, pp3560-3566, 2001

Authors:
Todd S. Gross, Nazri bin Kamsah and Igor I. Tsukrov
University of New Hampshire, Durham, USA

Room-temperature scanning probe microscopy was used to generate out-of-plane deformation maps around Cu vias and... more Room-temperature scanning probe microscopy was used to generate out-of-plane deformation maps around Cu vias and polyimide mesas in single-level Cu–polyimide damascene interconnect structures subjected to a room-temperature to 350 °C thermal cycle. The deformation maps are obtained by taking the difference between the images obtained before and after thermal processing. The deformation of the Cu is shown to be highly heterogeneous on the submicrometer scale. Direct evidence of Cu–Ta interfacial sliding, Cu–Cu grain boundary sliding, and diffusion creep is presented. The direction of Cu–Ta sliding is shown to depend on polyimide mesa size. A hot-stage atomic force microscope was used to show that hillock/extrusion growth occurs at temperatures between 130 and 180 °C. We propose that this hillock/extrusion growth is correlated with dips in stress–temperature plots for blanket, uncapped Cu films in the same temperature range and that the absence of dips for nitride-capped Cu films is due to suppression of the hillock/extrusion growth.

Development of Vapor Pressure in FR4-Copper Composite Material During Solder Reflow Process

by Nazri Kamsah

Nazri Kamsah, Mohd Nasir Tamin, Haslinda Mohamed Kamar, Hidayatunnur Lahuri and Amir Nur Rashid Wagiman

THIS PAPER IS STILL UNDER REVIEW..
It was submitted for the The International Meeting on Advances in Thermofluids (IMAT) 2011 to held in Malacca, Malaysia, October 2011

This paper presents a finite element (FE) methodology for predicting the distribution of vapor pressure in a simple... more This paper presents a finite element (FE) methodology for predicting the distribution of vapor pressure in a simple FR4-copper composite material when it is heated up to 215°C. A general purpose finite element software was used to develop a two-dimensional plane strain model of the composite material. FE simulation of transient moisture absorption was performed to predict the distribution of wetness fraction in the material after pre-conditioning at an 85°C/85%RH environment for 15 days. FE simulation of transient moisture desorption was carried out at the peak solder reflow temperature of 215°C to predict new distribution of wetness fraction in the material. The results of the moisture desorption analysis were used to compute the magnitude of vapor pressure in the material and its distribution at 215°C. It was found that the moisture in the material redistributes itself during solder reflow. The moisture concentration in the area close to the FR4-copper interface below the longer copper trace increases during the solder reflow. The magnitude of the vapor pressure in 70% of the FR4 and near the FR4-copper interface below the lower copper trace is closed to the saturation pressure of water vapor at 215°C. The distribution of the vapor pressure in the material is in similar fashion as the new distribution of wetness fraction after the moisture desorption analysis..