SebastianSager: SebastianSager moved page Supermarket refrigeration system (C) to Supermarket refrigeration system (Muscod) without leaving a redirect: Moved C to Muscod

2016-01-28T09:24:03Z

SebastianSager moved page Supermarket refrigeration system (C) to Supermarket refrigeration system (Muscod) without leaving a redirect: Moved C to Muscod

← Older revision	Revision as of 09:24, 28 January 2016
(No difference)

SebastianSager: Moved C to Muscod

2016-01-28T09:23:53Z

Moved C to Muscod

← Older revision		Revision as of 09:23, 28 January 2016
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	The differential equations for the [[Supermarket refrigeration system]] in [[:Category:C \| C code]] read as follows		The differential equations for the [[Supermarket refrigeration system]] in [[:Category:Muscod \| Muscod code]] read as follows

	<source lang="cpp">		<source lang="cpp">
Line 83:		Line 83:
	</source>		</source>

	[[Category:C]]		[[Category:Muscod]]

SebastianSager: Initial setup

2009-08-11T16:07:59Z

Initial setup

New page

The differential equations for the [[Supermarket refrigeration system]] in [[:Category:C | C code]] read as follows

<source lang="cpp">
// number of compressors
#define NVALVES 2

// constants
#define M_GOODS 200.0
#define C_P_GOODS 1000.0
#define UA_GOODS_AIR 300.0
#define M_WALL 260.0
#define C_P_WALL 385.0
#define UA_AIR_WALL 500.0
#define M_AIR 50.0
#define C_P_AIR 1000.0
#define UA_WALL_REF_MAX 4000.0
#define M_REF_MAX 1.0
#define TAU_FILL 40.0
#define T_SH 10.0
#define V_SUC 5.0
#define V_SL 0.08 // 2 display cases - 2 compressors
// #define V_SL 0.095 // 3 display cases - 3 compressors
#define ETA_VOL 0.81

// disturbances - day scenario
#define Q_AIRLOAD 3000.0
#define M_REF_CONST 0.2

// disturbances - night scenario
// #define Q_AIRLOAD 1800.0
// #define M_REF_CONST 0.0

double delta_h = (0.0217*xd[0]*xd[0] - 0.1704*xd[0] + 2.2988)*1e5;
double T_e = -4.3544*xd[0]*xd[0] + 29.224*xd[0] - 51.2005;
double rho_suc = 4.6073*xd[0] + 0.3798;
double rho_suc__P_suc = -0.0329*xd[0]*xd[0]*xd[0] + 0.2161*xd[0]*xd[0] - 0.4742*xd[0] + 5.4817;
double f = (0.0265*xd[0]*xd[0]*xd[0] -0.4346*xd[0]*xd[0] + 2.4923*xd[0] + 1.2189)*1e5;

double Q_goods_air[NVALVES];
double Q_air_wall[NVALVES];
double UA_wall_ref[NVALVES];
double Q_e[NVALVES];
double m[NVALVES];

double m_in_suc = 0.0;

int i;

for (i=0; i<NVALVES; i++){
Q_goods_air[i] = UA_GOODS_AIR*(xd[1 + i*4] - xd[3 + i*4]);
Q_air_wall[i] = UA_AIR_WALL*(xd[3 + i*4] - xd[2 + i*4]);
UA_wall_ref[i] = UA_WALL_REF_MAX * xd[4 + 4*i]/M_REF_MAX;
Q_e[i] = UA_wall_ref[i]*(xd[2 + 4*i] - T_e);

m[i] = Q_e[i]/delta_h;
m_in_suc += m[i];
}

double V_comp = 0.0;
double comp_scale = (double) 1.0/NCOMPS;
V_comp = comp_scale*u[NVALVES]*ETA_VOL*V_SL;

// suction pressure
rhs[0] = (m_in_suc + M_REF_CONST - V_comp*rho_suc) / (V_SUC*rho_suc__P_suc);

// for each display/valve
for (i=0; i<NVALVES; i++){

// temperatures:

// goods
rhs[1 + i*4] = - Q_goods_air[i]/(M_GOODS*C_P_GOODS);

// wall
rhs[2 + i*4] = (Q_air_wall[i] - Q_e[i])/(M_WALL*C_P_WALL);

// air
rhs[3 + i*4] = ((Q_goods_air[i] + Q_AIRLOAD - Q_air_wall[i]) /(M_AIR*C_P_AIR));

// mass of liquefied refrigerant:
rhs[4 + i*4] = ((M_REF_MAX - xd[4 + 4*i])/TAU_FILL * u[i] - m[i] * (1 - u[i]));
}
</source>

[[Category:C]]

Supermarket refrigeration system (Muscod) - Revision history

SebastianSager: SebastianSager moved page Supermarket refrigeration system (C) to Supermarket refrigeration system (Muscod) without leaving a redirect: Moved C to Muscod

SebastianSager: Moved C to Muscod

SebastianSager: Initial setup