From 7f60ea012dd2524dae921a2a35adbf7ef21f2bb6 Mon Sep 17 00:00:00 2001 From: prashantsinalkar Date: Tue, 10 Oct 2017 12:27:19 +0530 Subject: initial commit / add all books --- 3681/CH4/EX4.15/Ans4_15.PNG | Bin 0 -> 7943 bytes 3681/CH4/EX4.15/Ex4_15.sce | 25 +++++++++++++++++++++++++ 2 files changed, 25 insertions(+) create mode 100644 3681/CH4/EX4.15/Ans4_15.PNG create mode 100644 3681/CH4/EX4.15/Ex4_15.sce (limited to '3681/CH4/EX4.15') diff --git a/3681/CH4/EX4.15/Ans4_15.PNG b/3681/CH4/EX4.15/Ans4_15.PNG new file mode 100644 index 000000000..7361446c0 Binary files /dev/null and b/3681/CH4/EX4.15/Ans4_15.PNG differ diff --git a/3681/CH4/EX4.15/Ex4_15.sce b/3681/CH4/EX4.15/Ex4_15.sce new file mode 100644 index 000000000..eec08cfeb --- /dev/null +++ b/3681/CH4/EX4.15/Ex4_15.sce @@ -0,0 +1,25 @@ +// Calculating the temperature rise and thermal time constant and rating of the machine +clc; +disp('Example 4.15, Page No. = 4.23') +// Given Data +D = 0.6;// Diameter of induction motor (in meter) +L = 0.9;// Length of induction motor (in meter) +out = 7500;// Output of induction motor (in W) +e = 0.9;// Efficiency +G = 375;// Weight of material (in kg) +h = 725;// Specific heat (in J/kg degree celsius) +Lem = 12;// Specific heat dissipation (in Watt per meter square degree celsius) +// Calculation of the temperature rise and thermal time constant of the machine +S = (%pi*D*L)+(2*%pi/4*D^(2));// Total heat dissipating surface (in meter square) +Q = (out/e)-out;// Losses (in Watts) +Tm = Q/(S*Lem);// Final temperature rise (in degree celsius) +Th = G*h/(S*Lem);// Time constant (in seconds) +disp(Tm,'(a) Final temperature rise (degree celsius) ='); +disp(Th,' Time constant (seconds) ='); +// Calculation of the rating of the machine +Lem_new = 25;// Specific heat dissipation (in Watt per meter square degree celsius) +Q = Tm*S*Lem_new;// Losses (in Watts) +out = (e*Q)/(1-e);// Output of induction motor (in W) +disp(out,'(b) Rating of the machine (Watt) ='); +//in book answers are 30.85 degree celsius, 10025 seconds and 15687 watts. The answers vary due to round off error + -- cgit