Team:ZJUT-China/Model
ZJUT-China
Modeling
This year our team created a fermenter model of our light-induced self-lysin system. Our model informed the possible positions for company to input the light source. And it also provide cost budget in fermentation process for reference. This model, presenting below, consists of the ideal figure of fermenter and calculating process of the cost budget.
For Gold Medal Criterion #3
We developed our model with two main goals:
- Offering two options to input the LED lamps.
- Calculating the cost of our biological crushing method and comparing it with traditional mechanical one.
I. Fermentation Tank Model
- Figure 1: Two possible positions to input the LED lamp:①fixing in the side of the fermentation tank;②fixing on the stirring shaft and rotating with the stirring shaft.
Annotations:
- The choice of light source:
- Considering that the fermentation broth is a multi-solute turbid solution and the flow of fermentation liquid will have a greater impact on the light-emitting device, we choose scattered high-power LED blue light source. It has many advantages such as high purity, low spectrum, low energy consumption, which suited for the process of fermentation.
- Related LED lights parameters：
- Wavelength λ = 435nm
- power P = 3W
- luminous flux Φ = 80lm (generally between 80 ~ 100lm / W)
- price k= 55 yuan
- Fermentation tank parameters:
- diameter D = 5280mm;
- height H = 11617mm;
- oval head short axle b = 1320mm
II. Cost Budget Model
- The required number of lamps
- According to the experiment, light intensity should reach 20lux. In the Fermenter’s center cross section, the average illuminance (Eav) can be calculated with the following equation:
- Φ- luminous flux of one lamp
- N - the number of lamps
- CU - the space utilization factor (the ratio of the luminous flux reaching the illuminated surface to the total luminous flux emitted by the fixture), which is related to the design of the LED lamp, the height of the installation, the geometric characteristics of the space and the reflectivity.
- K - maintenance factor (light loss factor, the ratio of average illumination after a period of fermentation process to the average illumination while the system is on installation.
- S - surface area
- Thus the number of LED lights can be expressed as:
- Take CU = 0.6; K = 0.4;Φ = 80lm
- We can conclude that:
- Thus in all we need 21 LED lamps.
- Cost budget of blue-light system
- Suppose that the cost of one tank(C) consists of three parts: Electricity (E), Equipment cost (EC) and Maintenance Cost(MC).
-----③- With regard to Electricity Cost:
-----④- P-the power of each LED lamp
- T- work time
- K1- Electricity per kWh
- Equipment cost consist of fermentation tank renovation fee(Tube type for 2000yuan, Baffle type for 4000yuan, here we choose the average price 3000yuan) and the cost of LED lamps:
-----⑤- K -price of one LED lamp
- Supposing that the work time limit of LED is 6000h, the Maintenance Cost include the cost of purchasing new LED lamps:
-----⑥- Replace the variables in ③ with ④⑤⑥.Take P=0.003kw, N=21, k=55yuan, k1=1yuan/kwh( generally between 0.86 and 1.8).We can conclude that:
- Comparing with traditional mechanical method
- Take Xinhai biological company for example, Equipment cost (Homogenizer) is 25000yuan. Supposing that the additional Maintenance fees are 5000yuan per 6000 hour and the Electricity is 1.15yuan per hour. Thus the cost of traditional broken way C1 can be described as:
-----③- Then figure these two functions:
- Code: t=linspace(0,1000000);
- f1=(fix(t-6000)+1).*1155+3000+0.063.*t;
- f2=1.15.*t+250000+5000.*fix(t-6000);
- plot(t,f1);
- hold on
- plot(t,f2);
- Cost difference
- While for the first 6000 working hour of these light system (ignoring the Maintenance Cost), the cost difference of these two methods is:
-----③- Thus in the beginning it can help the constant save about 20845yuan.
