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Hydraulic model of a wide river of rectangular cross section is to be constructed at the laboratory. Some of the known parameters of the prototype are: hp=2.0m, Bp=100 m, (Ks)p=0.03m, Sp=0.0004, Lp=500m, Qp=100m3/s, Vm=1.0x10-6m2/s if the model area to be used at the laboratory has the maximum dimensions of 20.0 x60.0m and the maximum flow discharge to be supplied from the laboratory is (Qmax)=0.50m3/s; a/ determine the length scale of the model b/ If you are asked to make a distorted model of this river, determine, Xr, Yr, hm, Sm, (Ks)m, Bm, and Qm.

User Justberare
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Final answer:

The answer involves applying principles of Engineering to determine the scale and parameters for a hydraulic model of a river, based on the given physical and flow characteristics of the prototype and the limitations

Step-by-step explanation:

The correct answer is option E (Engineering). To construct a hydraulic model, specific scale factors and model parameters must be calculated based on constraints such as the maximum laboratory area and the maximum available discharge.

Length Scale: The length scale (Xr) is the ratio of the model's length to the prototype's length. Given the maximum dimensions of the laboratory area (20.0 x 60.0m), this limitation will guide the determination of the Xr value. Since the maximum laboratory length is significantly less than the prototype's length, the length scale will be less than 1.

Distorted Model Parameters: For a distorted model, besides Xr, we also need to determine the scale factors for width (Yr), depth (hm), slope (Sm), roughness (Ks)m, width (Bm), and discharge (Qm). The width, depth, and discharge scales are constrained by the laboratory's maximum width, depth, and discharge capacity.

Typically, distorted models can have different scale ratios for horizontal and vertical dimensions, allowing for a more manageable model within given constraints.

The calculation of each parameter requires extensive use of similarity laws such as Froude's or Reynolds' scaling, considering fluid properties and ensuring that flow behavior such as turbulence in the prototype is accurately represented in the model.

User Trillion
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