MODEL AND COMPUTER PROGRAM FOR HEAT TRANSFER ANALYSIS IN STRIP BRUSH PROTECTED RAILROAD SWITCH SYSTEMS Pavan Ravulaparthy and Ernesto Gutierrez-Miravete.

Slides:



Advertisements
Similar presentations
Quiz – An organic liquid enters a in. ID horizontal steel tube, 3.5 ft long, at a rate of 5000 lb/hr. You are given that the specific.
Advertisements

Heat Transfer with Change of Phase in Continuous Casting Ernesto Gutierrez-Miravete Rensselaer at Hartford ANSYS Users Group Meeting September 28, 2010.
Experiment -6 Determination of Heat Transfer Coefficients by remote control ENTC 370PROF. ALVARADO 1.
An Analysis of Hiemenz Flow E. Kaufman and E. Gutierrez-Miravete Department of Engineering and Science Rensselaer at Hartford.
Heat Transfer Chapter 2.
Chapter 11 Energy in Thermal Processes Heat and Internal Energy
Calorimetry Review : Specific Heat, Latent Heat, & Temperature vs. Heat Input plot Chapter 14.
Analysis of Simple Cases in Heat Transfer P M V Subbarao Professor Mechanical Engineering Department I I T Delhi Gaining Experience !!!
Thermodynamics can be defined as the science of energy. Although everybody has a feeling of what energy is, it is difficult to give a precise definition.
Mathematical Modeling of Inclusion Dissolution Processes: The GROW Code Ernesto Gutierrez-Miravete Rensselaer at Hartford Brice Cassenti United Technologies.
MECh300H Introduction to Finite Element Methods
Laser Treatment Modeling Capabilities at Rensselaer-Hartford Ernesto Gutierrez-Miravete Rensselaer at Hartford
An Analysis of Plunger Temperature during Glass Parison Pressing
Finite Element Modeling with COMSOL Ernesto Gutierrez-Miravete Rensselaer at Hartford Presented at CINVESTAV-Queretaro December 2010.
Ambient temperature inside an automobile subject to external conditions. MeEn 340 By Eric McKane and Benton Russell.
An Analysis of Heat Conduction with Phase Change during the Solidification of Copper Jessica Lyn Michalski 1 and Ernesto Gutierrez-Miravete 2 1 Hamilton.
Food Freezing Basic Concepts (cont'd) - Prof. Vinod Jindal
MATHEMATICAL MODEL OF A Hybrid solar panel
Dr. Xia Wang Assistant Professor Department of Mechanical Engineering Tel: Fax: Contact.
Chapter 3.1: Heat Exchanger Analysis Using LMTD method
Some Like it Hot and Some Sweat when the Heat is On!!!
by Peter Tu An Engineering Project Submitted to the Graduate
Thermodynamics Part II. Remaining Topics Mechanisms of Heat Transfer Thermodynamic Systems and Their Surrounding Thermal Processes Laws of Thermodynamics.
P.M.Pavel and M.Constantinescu. ICF-AR “Ilie Murgulescu” Bucuresti Romanian Academy of Science Institute of Physical Chemistry “Ilie Murgulescu” Spl. Independentei.
Tutorial 2a: Energy flow-paths Q1. Give 3 reasons why two different walls of the same U-value might give rise to substantially different energy requirements.
Thermal Properties of Matter
Physics I Basic Concepts of Thermodynamics Prof. WAN, Xin
Unsteady Heat Transfer Many heat transfer problems require the understanding of the complete time history of the temperature variation. For example, in.
Convection Part1 External Flow. Introduction Recall: Convention is the heat transfer mode between a fluid and a solid or a 2 fluids of different phases.
Molecular Transport Equations. Outline 1.Molecular Transport Equations 2.Viscosity of Fluids 3.Fluid Flow.
ENT 255 HEAT TRANSFER BASICS OF HEAT TRANSFER. THERMODYNAMICS & HEAT TRANSFER HEAT => a form of energy that can be transferred from one system to another.
Mathematical Equations of CFD
Using the “Clicker” If you have a clicker now, and did not do this last time, please enter your ID in your clicker. First, turn on your clicker by sliding.
Determine the heat capacity (in calories/C°) of a lake containing two million gallons (approximately 8 million kilograms) of water at 15C°. Select.
An adiabatic free expansion of a gas in a thermally isolated container is not reversible because _____ . Select the correct answer. work must be.
11/17/2014PHY 711 Fall Lecture 351 PHY 711 Classical Mechanics and Mathematical Methods 10-10:50 AM MWF Olin 103 Plan for Lecture 35: Chapter 11.
METR February Review Hydrostatic balance Pressure decreases exponentially with height, isothermal atmosphere: Zeroth law of thermodynamics:
حرارة وديناميكا حرارية
Heat Transfer Equations. Fouling Layers of dirt, particles, biological growth, etc. effect resistance to heat transfer We cannot predict fouling factors.
Food Freezing Basic Concepts (cont'd) - Prof. Vinod Jindal 1 FST 151 FOOD FREEZING FOOD SCIENCE AND TECHNOLOGY 151 Food Freezing - Basic concepts (cont’d)
MECH4450 Introduction to Finite Element Methods
INTRODUCTION TO CONVECTION
HW/Tutorial # 1 WRF Chapters 14-15; WWWR Chapters ID Chapters 1-2
HW/Tutorial # 1 WRF Chapters 14-15; WWWR Chapters ID Chapters 1-2 Tutorial #1 WRF#14.12, WWWR #15.26, WRF#14.1, WWWR#15.2, WWWR#15.3, WRF#15.1, WWWR.
Thermal Analysis Assumptions: Body Temperature (Environment) is 37˚C Heat distribution on outside of device will be modeled via FEA Heat transfer method.
11/11/2015PHY 711 Fall Lecture 311 PHY 711 Classical Mechanics and Mathematical Methods 10-10:50 AM MWF Olin 103 Plan for Lecture 31: Chapter 11.
PHYSICS – Thermal properties and temperature (2)..
Cooling of GEM detector CFD _GEM 2012/03/06 E. Da RivaCFD _GEM1.
Investigation of Thin Film Evaporation Limit in Single Screen Mesh Layers Presented to IMECE 2002 Nov. 19, 2002, New Orleans, LA Yaxiong Wang & G.P. “Bud”
Heat Exchange. HOW IS THERMAL ENERGY TRANSFERRED? 3 MECHANISMS: CONDUCTION CONDUCTION CONVECTION CONVECTION RADIATION RADIATION.
Heat Transfer Su Yongkang School of Mechanical Engineering # 1 HEAT TRANSFER CHAPTER 6 Introduction to convection.
Transferência de Energia e de Massa Energy and Mass Transfer Lecture 1: Introduction to the subject and to the course 1.
Chapter 19 Heat and the First Law of Thermodynamics 19-1 Heat as Energy Transfer 19-2 Internal Energy 19-3 Specific Heat 19-4 Calorimetry 19-5 Latent Heat.
Heat transfer mechanism Dhivagar R Lecture 1 1. MECHANISMS OF HEAT TRANSFER Heat can be transferred in three different ways: conduction, convection, and.
HW/Tutorial # 1 WRF Chapters 14-15; WWWR Chapters ID Chapters 1-2
14-6 Heat Transfer: Conduction
MODUL KE SATU TEKNIK MESIN FAKULTAS TEKNOLOGI INDUSTRI
Thermodynamics.
Fundamentals of Heat Transfer
Mathematics and Home Insulation
{ } { } melting Latent Heat Gas Boiling condensing (evaporating) Water has three phases or states: Solid (ice) Liquid Gas (steam, water vapour)
Heat Exchangers Heat Exchangers.
Heat Transfer In Channels Flow
Heat Exchangers Heat Exchangers.
Convective Heat Transfer
What are Fins ? Fins are extended surfaces used to increase the rate of heat transfer. It is made of highly conductive materials such as aluminum.
Complete chart for 18 minutes
Fundamentals of Heat Transfer
Chapter 2: Energy and the First Law of Thermodynamics
Conservation of Energy
Presentation transcript:

MODEL AND COMPUTER PROGRAM FOR HEAT TRANSFER ANALYSIS IN STRIP BRUSH PROTECTED RAILROAD SWITCH SYSTEMS Pavan Ravulaparthy and Ernesto Gutierrez-Miravete Rensselaer at Hartford

Heated Railroad Switch Systems

Strip Brush Protected Railroad Switch

Mathematical Model Concept Thermal energy introduced into the switch by the heating system is transported first across the narrow air gap that separates the brush from the switch, then through the brush bristles and finally through the snow layer and into the surrounding environment. The latent heat of melting of the snow is taken into account.

Boundary and Initial Conditions For boundary conditions, at the rail boundary we assume that, for safety reasons, the temperature of the switch cannot be allowed to fall below a preselected, well-defined value. On the external surface of the snow, heat is exchanged with the environment through the action of a suitably selected heat transfer coefficient. Regarding the initial condition of the problem, a reasonable temperature profile across the multi- layer system is assumed.

Heat Conduction with Change of Phase: Governing Equations and Approximation Method ρ C p,eff ∂ T/∂t = k ∇ 2 T C p,eff = C p,eff (T) T n+1 j = T n j + (Δt k j / ρ j C pj ) (T n j-1 – 2 T n j + T n j+1 )/ Δx 2

SnowProtec.f Inputs for the program include the physical properties and dimensions of all materials involved (air, brush bristles, snow), as well as the temperature of the surrounding environment and the power of the switch heating unit. The program computes the temperature profile across the air gap-brush-snow layer system as a function of time.

Computed Temperature History

Computed Temperature Profiles: Air Gap-Brush-Snow Pack

Conclusions The SnowProtec system provides mechanical and thermal isolation of the switch from the surrounding environment that results in savings in the energy required for the maintenance of the proper operating condition of the switch system. A mathematical model of the SnowProtec system provides additional evidence about the protective mechanism provided by the brush seal.