Functional Requirements

This section provides the functional requirements, the tasks and behaviours that the software is expected to complete.

Input-Values: Input the values from Tab:ReqInputs, which define the tank parameters, material properties, and initial conditions.

Find-Mass: Use the inputs in FR:Input-Values to find the mass needed for IM:eBalanceOnWtr, using DD:waterMass, DD:waterVolume_nopcm, and DD:tankVolume.

Check-Input-with-Physical_Constraints: Verify that the inputs satisfy the required physical constraints.

Output-Input-Derived-Values: Output the input values and derived values in the following list: the values (from FR:Input-Values), the mass (from FR:Find-Mass), and ${τ_{\text{W}}}$ (from DD:balanceDecayRate).

Calculate-Values: Calculate the following values: ${T_{\text{W}}}$ ( $t$ ) (from IM:eBalanceOnWtr) and ${E_{\text{W}}}$ ( $t$ ) (from IM:heatEInWtr).

Output-Values: Output ${T_{\text{W}}}$ ( $t$ ) (from IM:eBalanceOnWtr) and ${E_{\text{W}}}$ ( $t$ ) (from IM:heatEInWtr).

Symbol	Description	Units
${A_{\text{C}}}$	Heating coil surface area	${\text{m}^{2}}$
${A_{\text{tol}}}$	Absolute tolerance	–
${C_{\text{W}}}$	Specific heat capacity of water	$\frac{\text{J}}{\text{kg}{}^{\circ}\text{C}}$
$D$	Diameter of tank	${\text{m}}$
${E_{\text{W}}}$	Change in heat energy in the water	${\text{J}}$
${h_{\text{C}}}$	Convective heat transfer coefficient between coil and water	$\frac{\text{W}}{\text{m}^{2}{}^{\circ}\text{C}}$
$L$	Length of tank	${\text{m}}$
${R_{\text{tol}}}$	Relative tolerance	–
${T_{\text{C}}}$	Temperature of the heating coil	${{}^{\circ}\text{C}}$
${T_{\text{init}}}$	Initial temperature	${{}^{\circ}\text{C}}$
${t_{\text{final}}}$	Final time	${\text{s}}$
${t_{\text{step}}}$	Time step for simulation	${\text{s}}$
${ρ_{\text{W}}}$	Density of water	$\frac{\text{kg}}{\text{m}^{3}}$

Required Inputs

Software Requirements Specification for Solar Water Heating Systems

Functional Requirements