From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001 From: priyanka Date: Wed, 24 Jun 2015 15:03:17 +0530 Subject: initial commit / add all books --- 1943/CH8/EX8.2/Ex8_2.sce | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) create mode 100755 1943/CH8/EX8.2/Ex8_2.sce (limited to '1943/CH8/EX8.2') diff --git a/1943/CH8/EX8.2/Ex8_2.sce b/1943/CH8/EX8.2/Ex8_2.sce new file mode 100755 index 000000000..8bde8e1b2 --- /dev/null +++ b/1943/CH8/EX8.2/Ex8_2.sce @@ -0,0 +1,42 @@ + +clc +clear +//Input data +ws=20;//The amount of dry saturated steam received by a surface condencer in t/h +tsh=40;//The temperature of dry saturated steam in degree centigrade +wa=(0.35/1000);//The mass flow rate of air per 1000 kg of steam in kg +tc=38;//The temperature at which condensate leaves the temperature in degree centigrade +tm=10;//The temperature at which makeup water is supplied in degree centigrade +tc1=32;//The inlet temperature of cooling water in degree centigrade +tc2=38;//The outlet temperature of cooling water in degree centigrade +tas=27;//The temperature of air along with steam in degree centigrade +psat=0.07384;//The saturated pressure at 40 degree C in bar +vg=19.52;//The specific volume at 40 degree C in m^3/kg +R=0.287;//Real gas constant in kJ/kgK +Cpc=4.187;//The specific heat of water in kJ/kgK +Cp=1.005;//The specific heat of air in kJ/kgK + +//Calculations +pair=[(wa*R*(tsh+273)*1000)/vg]*10^-5;//The pressure of air in bar +psat1=0.06624;//The saturated pressure at 38 degree C in bar +vg1=21.63;//The specific volume at 38 degree C in m^3/kg +pair1=psat-psat1;//The pressure of air in bar +wa1=(ws*1000)*wa;//Mass of air removed per hour in kg/h +V1=((wa1*R*(273+tc2)*1000))/(pair1*10^5);//Volume of air remove per hour +ws1=V1/vg1;//The mass of steam accompanying air in kg/h +psat2=0.03564;//The saturated pressure at 27 degree C in bar +vg2=38.81;//The specific volume at 27 degree C in m^3/kg +pair2=psat-psat2;//The pressure of air in bar +V2=(wa1*R*1000*(tas+273))/(pair2*10^5);//Volume of air removed per hr in m^3/hr +ws2=V2/vg2;//The mass of steam accompanying air in kg/h +ws3=ws1-ws2;//Saving mass of steam by using seperate extraction in kg/hr +Q3=[ws3*Cpc*(tc-tm)]/3600;//Saving in heat supply in the boiler in kW +V=[(V1-V2)/V1]*100;//Percentage reduction in air ejector load in % +hc=159.3;//Enthalpy at 38 degree C in kJ/kg +hs1=2574.3;//Enthalpy at 40 degree C in kJ/kg +hs2=2550.3;//Enthalpy at 27 degree C in kJ/kg +Q2=[[(ws*1000)*(hs1-hc)]-[(wa1*(Cp*(tsh-tas)))]-(ws3*hs2)]/3600;//The amount of heat in kW +wc=Q2/(Cpc*(tc2-tc1));//The mass flow rate of water in kg/s + +//Output +printf('(a) The rate of saving of condensate and the rate of saving in the heat supply in the boiler due to seperate air extraction pump = %3.3f kW \n (b) The percentage reduction in air ejector load due to this seperate air extraction method = %3.1f percent \n (c) The rate of cooling water flow = %3.0f kg/s ',Q3,V,wc) -- cgit