List of Computer aided design Lab. Experiments.pdf
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The document outlines various laboratory experiments in chemical engineering, detailing problems, mathematical models, and subject areas, such as material balances, heat exchange, and chemical reactions. It includes experiments from CAD, modeling and simulation labs, and presents mathematical equations necessary for solving each problem. Additionally, it addresses specific case studies involving flow conditions, relief vent sizing, and electrical charge accumulation in fluid lines.
![CAD Lab. CH Exp-7 21/03/2018
GT≃0.9Ψ
ΔP
ΔT √gcTs
CP (5)
ΔP is the over pressure and ΔT is the temperature rise corresponding to over pressure.
The required vent area is computed by solving a particular form of dynamic energy balance equation
A=
mo q
GT (√VΔHv
mo νfg
+√CV ΔT)
2
(6)
Alternative form of equation-6 can be used to find relief area
A=
mo q
GT (√V
mo
Ts
dP
dT
+√CV ΔT
)
2
(7)
mo =Total mass contained within the reactor vessel before relief
q =Exothermic heat release per unit mass
V =Volume of the vessel and
CV = the liquid heat capacity at constant volume.
Exothermic heat release per unit mass can be computed through experimentation by obtained by
Vent Sizing Packaging data, using the following equation
q=
1
2
CV [(dT
dt )s
+(dT
dt )m] (8)
Subscripts s denotes corresponding to the heating rate at set pressure and the m corresponding to
the temperature rise at the maximum turn around pressure.
Problem Statement
Leung9
reported on the data of Huff10
involving a 3500-gal reactor with styrene monomer
undergoing adiabatic polymerization after being heated inadvertently to 70°C. The maximum
allowable working pressure (MAWP) of the vessel is 5 bar. Given the following data,
determine the relief vent diameter required. Assume a set pressure of 4.5 bar and a maximum
pressure of 5.4 bar absolute:
Data:
Volume: 3500 gal=13.16 m3
Reaction Mass=9500 kg
Set temperature=209.4o
C=482.5K
VSP Data
Maximum temperature Tm=219.5o
C=492.7 K
(dT
dt )s =29.6 o
C/min=0.493 K/s
(dT
dt )m =39.7 o
C/min=0.662 K/s
Physical property data
4.5 –bar set 5.4-bar Peak
νf (m3
/kg)
0.001388 0.001414
νg (m3
/kg)
0.08553 0.07278
CP (kJ/kg K)
2.470 2.514](https://image.slidesharecdn.com/listofcomputeraideddesignlab-241104121147-defe9a36/85/List-of-Computer-aided-design-Lab-Experiments-pdf-13-320.jpg)
2
[1−exp(−
L
uτ )] (1)
Is is the streaming current (amps),
u is the velocity (m/s),
d is the pipe diameter (m),
L is the pipe length (m), and
τ is the liquid relaxation time (seconds).
The relaxation time is the time required for a charge to dissipate by leakage. It is determined
using
τ =
εr εo
γc (2)
Where
τ is the relaxation time (seconds),
εr is the relative dielectric constant (unitless),
εo is the permittivity constant, that is,
γc is the specific conductivity (mho/cm)
Electrostatic Voltage Drops in the tank feed line can be calculated as V=Is.R and resistance can be computed as
R=
L
γc A , where L and A are the length and area of the conductor respectively. Energy of charged capacitors
and charge accumulated can be calculated using following
J=
QV
2
=
CV
2
2 (3)
Q=Is t (4)](https://image.slidesharecdn.com/listofcomputeraideddesignlab-241104121147-defe9a36/85/List-of-Computer-aided-design-Lab-Experiments-pdf-15-320.jpg)
List of Computer aided design Lab. Experiments.pdf
- 1. List of CAD Lab. Experiments Sl. No PROBLEM TITLE MATHEMATICAL MODEL SUBJECT AREA 1 Molar Volume and Compressibility Factor from Van Der Waals Equation Single Nonlinear Equation Introduction to Ch. E. 2 Steady State Material Balances on a Separation Train Simultaneous Linear Equations Introduction to Ch. E. 3 Vapor Pressure Data Representation by Polynomials and Equations Polynomial Fitting, Linear and Nonlinear Regression Mathematical Methods 4 Reaction Equilibrium for Multiple Gas Phase Reactions Simultaneous Nonlinear Equations Thermodynamics 5 Terminal Velocity of Falling Particles Single Nonlinear Equation Fluid Dynamics 6 Unsteady State Heat Exchange in a Series of Agitated Tanks Simultaneous ODE’s with known initial conditions. Heat Transfer 7 Diffusion with Chemical Reaction in a One Dimensional Slab Simultaneous ODE’s with split boundary conditions. Mass Transfer 8 Binary Batch Distillation Simultaneous Differential and Nonlinear Algebraic Equations Separation Processes 9 Reversible, Exothermic, Gas Phase Reaction in a Catalytic Reactor Simultaneous ODE’s and Algebraic Equations Reaction Engineering 10 Dynamics of a Heated Tank with PI Temperature Control Simultaneous Stiff ODE’s Process Dynamics and Control Modelling & Simulation Lab. Experiments Sl. No PROBLEM TITLE 1 Simulation of biomass gasification in fluidized bed reactor using 2 Simulation of CO2 Removal from Coal and Gas Fired Power Plants 3 Optimization of crude distillation system 4 Simulation of commercial dimethyl ether production plant 5 Simulation of ethanol production processes based on enzymatic hydrolysis of woody biomass 6 Steady-state simulation of a novel extractive reactor for enzymatic biodiesel production
- 2. Computer Aided Design Lab Chemical Engg. Deptt. Group No.: Name(S): 1. 2. 3. 4. 5. PROBLEM TITLE: Steady State Material Balances on a Separation Train MATHEMATICAL MODEL: Simultaneous Linear Equations Answer:
- 3. CAD Lab. CH Exp-2 10/01/2018 Group No.: Name(S): 1. 2. 3. 4. 5. PROBLEM TITLE: Pressure Drop in Pipe MATHEMATICAL MODEL: Single Nonlinear Algebraic Equations Answer:
- 4. CAD Lab. CH Exp-3 17/01/2018 Group No.: Name(S): 1. 2. 3. 4. 5. PROBLEM TITLE: Initial Value Problems MATHEMATICAL MODEL: Solution of Single Ordinary Differential Equation Answer:
- 5. CAD Lab. CH Exp-4 17/01/2018 Group No.: Name(S): 1. 2. 3. 4. 5. PROBLEM TITLE: Initial Value Problems MATHEMATICAL MODEL: Solution of Single Ordinary Differential Equation
- 6. CAD Lab. CH Exp-4 17/01/2018 Answer:
- 7. CAD Lab. CH Exp-5 24/01/2018 Group No.: Name(S): 1. 2. 3. 4. 5. PROBLEM TITLE: Initial Value Problems MATHEMATICAL MODEL: Solution of Simultaneous Ordinary Differential Equations
- 8. CAD Lab. CH Exp-5 24/01/2018 PROBLEM: Answer:
- 9. CAD Lab. CH Exp-6 07/02/2018 Group No.: Name(S): 1. 2. 3. 4. 5. PROBLEM TITLE: Terminal Velocity MATHEMATICAL MODEL: Nonlinear Algebraic Equation
- 10. CAD Lab. CH Exp-6 07/02/2018
- 11. CAD Lab. CH Exp-6 07/02/2018 PROBLEM: Answer:
- 12. CAD Lab. CH Exp-7 21/03/2018 Group No.: Name(S): 1. 2. 3. 4. 5. Flow of vapors through relief Concepts Utilized: Assuming flow condition is choked Course Useage: relief sizing design Problem back ground: Normally gases are stored under high pressure. If the gas vents through a hole or relief device, choked flow condition exist. In such a cases, the mass flow rate of gas is computed as follows (Qm)choked=Co AP √γgc M RgT ( 2 γ+1) (γ +1/γ−1) (1) (Qm)choked =the discharge mass flow, Co =discharge coefficient A =area of discharge P = Absolute upstream pressure γ =heat capacity ratio for the gas gc =Gravitational constant M = Molecular wt of the gas Rg = Ideal gas constant T =Absolute temperature of the gas To perform relief sizing calculation for the two-phase vents, the mass flux GT through relief is computed assuming the choked flow GT= Qm A = ΔHv νfg √ gc CPTs (2) Equation-2 is called Equilibrium rate model for low-quality choked flow Qm =mass flow through the relief ΔHv =heat of vaporization of the fluid A =area of the hole νfg =change in specific volume of the flashing liquid CP =heat capacity of the fluid Ts =Absolute saturation temperature of the fluid at set pressure Leung further modified the equation-2 for homogeneous venting of a reactor GT= Qm A =0.9Ψ ΔHv νfg √ gc CP Ts (3) Equation-3 is called homogeneous equilibrium rate model. For a pipe of length 0, Ψ =1 As one know ΔHv νfg =Ts dP dT (4) Equation-3 can be rearrange using equation-4 in finite difference derivative after being approximated by exact derivative
- 13. CAD Lab. CH Exp-7 21/03/2018 GT≃0.9Ψ ΔP ΔT √gcTs CP (5) ΔP is the over pressure and ΔT is the temperature rise corresponding to over pressure. The required vent area is computed by solving a particular form of dynamic energy balance equation A= mo q GT (√VΔHv mo νfg +√CV ΔT) 2 (6) Alternative form of equation-6 can be used to find relief area A= mo q GT (√V mo Ts dP dT +√CV ΔT ) 2 (7) mo =Total mass contained within the reactor vessel before relief q =Exothermic heat release per unit mass V =Volume of the vessel and CV = the liquid heat capacity at constant volume. Exothermic heat release per unit mass can be computed through experimentation by obtained by Vent Sizing Packaging data, using the following equation q= 1 2 CV [(dT dt )s +(dT dt )m] (8) Subscripts s denotes corresponding to the heating rate at set pressure and the m corresponding to the temperature rise at the maximum turn around pressure. Problem Statement Leung9 reported on the data of Huff10 involving a 3500-gal reactor with styrene monomer undergoing adiabatic polymerization after being heated inadvertently to 70°C. The maximum allowable working pressure (MAWP) of the vessel is 5 bar. Given the following data, determine the relief vent diameter required. Assume a set pressure of 4.5 bar and a maximum pressure of 5.4 bar absolute: Data: Volume: 3500 gal=13.16 m3 Reaction Mass=9500 kg Set temperature=209.4o C=482.5K VSP Data Maximum temperature Tm=219.5o C=492.7 K (dT dt )s =29.6 o C/min=0.493 K/s (dT dt )m =39.7 o C/min=0.662 K/s Physical property data 4.5 –bar set 5.4-bar Peak νf (m3 /kg) 0.001388 0.001414 νg (m3 /kg) 0.08553 0.07278 CP (kJ/kg K) 2.470 2.514
- 14. CAD Lab. CH Exp-7 21/03/2018 ΔHv (kJ/kg ) 310.6 302.3
- 15. CAD Lab. CH Exp-8 28/03/2018 Group No.: Name(S): 1. 2. 3. 4. 5. ELECTRICAL CHARGE ACCUMULATION IN A FEED LINE RESULTING FROM FLUID FLOW. Numerical method: Solution of a linear algebraic equation. Concepts Utilized: Streaming current Course Useage: Controlling of electrostatic hazards Problem back ground: A streaming current Is is the flow of electricity produced by transferring electrons from one surface to another by a flowing fluid or solid. When a liquid or solid flows through a pipe (metal or glass), an electrostatic charge develops on the streaming material. This current is analogous to a current in an electrical circuit. The relation between a liquid streaming current and the pipe diameter, pipe length, fluid velocity, and fluid properties is given by Is= [10∗10−6 amp (m/s)2 m2 ](ud)2 [1−exp(− L uτ )] (1) Is is the streaming current (amps), u is the velocity (m/s), d is the pipe diameter (m), L is the pipe length (m), and τ is the liquid relaxation time (seconds). The relaxation time is the time required for a charge to dissipate by leakage. It is determined using τ = εr εo γc (2) Where τ is the relaxation time (seconds), εr is the relative dielectric constant (unitless), εo is the permittivity constant, that is, γc is the specific conductivity (mho/cm) Electrostatic Voltage Drops in the tank feed line can be calculated as V=Is.R and resistance can be computed as R= L γc A , where L and A are the length and area of the conductor respectively. Energy of charged capacitors and charge accumulated can be calculated using following J= QV 2 = CV 2 2 (3) Q=Is t (4)
- 16. CAD Lab. CH Exp-8 28/03/2018 Problem statement: Determine the voltage developed between a charging nozzle and a grounded tank, as shown in Figure. Also, compute the energy stored in the nozzle and the energy accumulated in the liquid. Explain the potential hazards in this process for a flow rate of a. 1 gpm b. 150 gpm The data are: Hose length: 20 ft Hose diameter: 2 in Liquid conductivity: mho/cm Dielectric constant: 25.7 Density: 0.88 g/cm3 Capacitance between the two 1-in flanges=20x10-12 coulomb/volt
- 17. CAD Lab. CH Exp-9 28/03/2018 Group No.: Name(S): 1. 2. 3. 4. 5. Numerical method: Solution of a non-linear algebraic equation. Concepts Utilized: Minimum Fluidization Velocity Course Usage: Fluidization Engineering Problem back ground:
- 18. CAD Lab. CH Exp-9 28/03/2018