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restart;#'therm_eq5.mws'.22-6-00. |
Chapter 5: Set of pre-written equations available.
Balance equations for the evolution of a control mass
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eq5_1:=dm=0;eq5_2:=m*dv=F[A]*dt+m*g*dt;eq5_3:=m*de=dW+dQ;eq5_4:=m*ds=Int(1/T,Q)+S[gen];eq5_4a:=m*dphi=W[u]+Int(1-T0/T,Q)-T0*S[gen]; |
Definition of total enthalpy
Balance equations for the evolution of a control volume
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eq5_14:=dm=Sum(dm[e],i=1..abert);eq5_15:=d(m*v)=F[A]*dt+m*g*dt-Sum(p[e]*A[e]*n[e]*dt,i=1..abert)+Sum(v[e]*dm[e],i=1..abert);eq5_16:=d(m*e)=dW+dQ+Sum(h[t,e]*dm[e],i=1..abert);eq5_17:=d(m*s)=Int(1/T,Q)+S[gen]+Sum(s[e]*dm[e],i=1..abert);eq5_18:=d(m*phi)=W[u]+Int(1-T0/T,Q)-T0*S[gen]+Sum((phi[e]+(p[e]-p0)/rho)*dm[e],i=1..abert);eq5_19:=d(m*phi)=W[u]+Int(1-T0/T,Q)-T0*S[gen]+Sum(psi[e]*dm[e],i=1..abert); |
Exergy flow and mass flow in a pipe
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eq5_19a:=psi=h[t]-T0*s;eq5_39:=m=rho*v*A; |
Balance equations for the steady evolution of a control volume
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eq5_39a:=0=Sum(rho*v*A,i=1..abert);eq5_39b:=0=F[A]+m*g-Sum(p*A*n,i=1..abert)+Sum(v*rho*v*A,i=1..abert);eq5_40:=0=W+Q+Sum(h[t]*rho*v*A,i=1..abert);eq5_41:=0=Int(1/T,Q)+S[gen]+Sum(s*rho*v*A,i=1..abert);eq5_41a:=0=W[u]+Int(1-T0/T,Q)-T0*S[gen]+Sum(psi*rho*v*A,i=1..abert); |
Energy balance for the steady evolution of a control volume with one input and one output
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eq5_43:=Dh[t]=w+q;eq5_43_1:=Qdot=mdot*c[p]*DT; |
Exergy balance for the steady evolution of a control volume with one input and one output
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eq5_44:=Dpsi=w+Int(1-T0/T,q)-T0*s[gen]; |
Variation of exergy from input to output (steady)
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eq5_45:=Dpsi=Dh[t]-T0*Ds; |
Extended Bernoulli's equation (mechanical energy balance, steady, one input and one output)
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eq5_46:=w=Int(p,1/rho)+De[m]+e[mdf];eq5_47:=Wdot_id=mdot*Dp[t]/rho; |
Total pressure for a perfect liquid
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eq5_55:=p[t]=p+(1/2)*rho*v^2+g*z; |
Total temperature for a perfect gas
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eq5_56:=T[t]/T=1+v^2/(2*c[p]*T); |
Efficiency of an adiabatic compressor and an adiabatic expansor with the perfect gas model
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eq5_59:=eta=(pi[12]^((gamma-1)/gamma)-1)/(T2/T1-1);eq5_60:=eta=(1-T4/T3)/(1-(1/pi[12])^((gamma-1)/gamma)); |
WARNING. A list of all variables follows, to copy and paste to the save command (after Maple7 there is no saving all). CAUTION: After pasting all, I must MANUALLY delete system variables: like RealRange_...
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save eq5_1, eq5_11, eq5_14, eq5_15, eq5_16, eq5_17, eq5_18, eq5_19, eq5_19a, eq5_2, eq5_3, eq5_39, eq5_39a, eq5_39b, eq5_4, eq5_40, eq5_41, eq5_41a, eq5_43, eq5_43_1, eq5_44, eq5_45, eq5_46, eq5_47, eq5_4a, eq5_55, eq5_56, eq5_59, eq5_60, "../therm_eq5.m":` |