User:BademiChetan - Revision history

BademiChetan at 11:14, 9 April 2011

2011-04-09T11:14:56Z

← Older revision		Revision as of 11:14, 9 April 2011
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			===Introduction===
	This is the model of a flat plate solar water heater.		This is the model of a flat plate solar water heater.

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	The model has been tested with all the data(example problems) mentioned in the book and give correct results. Improvements to the model would be deciding the angle of incidence based on the position of the sun, varying the wind transfer coefficient by using the data reader, etc.		The model has been tested with all the data(example problems) mentioned in the book and give correct results. Improvements to the model would be deciding the angle of incidence based on the position of the sun, varying the wind transfer coefficient by using the data reader, etc.

	Salient features ~~of the model:~~		===Salient features===

	1. Calculates HeatLossCoefficient and TempPlateMean by solving equations 6.4.9 and 6.9.4 iterativelys(Duffie and Beckman). This is very accurate compared to a model with approximations.		1. Calculates HeatLossCoefficient and TempPlateMean by solving equations 6.4.9 and 6.9.4 iterativelys(Duffie and Beckman). This is very accurate compared to a model with approximations.
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	3. Takes into account the transmission-absorptance product for various angles of incidences.		3. Takes into account the transmission-absorptance product for various angles of incidences.


			===Assumptions===


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	16. Wind transfer coefficient of assumed to be zero.		16. Wind transfer coefficient of assumed to be zero.

			===Source===
	<source lang="a4c">		<source lang="a4c">

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	</source>		</source>
			===Incidence Graph===
	[[Image:IncidenceGraph.png\|thumb\|1100px\|1100px\|Incidence Graph generated by ASCEND for the model of simple flat plate solar water heater]]		[[Image:IncidenceGraph.png\|thumb\|1100px\|1100px\|Incidence Graph generated by ASCEND for the model of simple flat plate solar water heater]]
			===Screenshot1===
	[[Image:FlatPlateSolarWaterHeaterValues1.png\|thumb\|1100px\|1100px\|Values obtained after solving the model of simple flat plate solar water heater part I]]		[[Image:FlatPlateSolarWaterHeaterValues1.png\|thumb\|1100px\|1100px\|Values obtained after solving the model of simple flat plate solar water heater part I]]
			===Screenshot2===
	[[Image:FlatPlateSolarWaterHeaterValues2.png\|thumb\|1100px\|1100px\|Values obtained after solving the model of simple flat plate solar water heater part II]]		[[Image:FlatPlateSolarWaterHeaterValues2.png\|thumb\|1100px\|1100px\|Values obtained after solving the model of simple flat plate solar water heater part II]]

BademiChetan at 11:08, 9 April 2011

2011-04-09T11:08:16Z

← Older revision		Revision as of 11:08, 9 April 2011
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			This is the model of a flat plate solar water heater.

	~~<source lang="a4c">~~		It's basically follows the equations and relations in Chapter 6, Solar Engineering for Thermal Processes by Duffie and Beckman,
	(*
			In the method on_load, certain parameters have been fixed. These can be varied and results for different parameters can be obtained. Some sample screen shots are attached.

			The model has been tested with all the data(example problems) mentioned in the book and give correct results. Improvements to the model would be deciding the angle of incidence based on the position of the sun, varying the wind transfer coefficient by using the data reader, etc.

			Salient features of the model:

			1. Calculates HeatLossCoefficient and TempPlateMean by solving equations 6.4.9 and 6.9.4 iterativelys(Duffie and Beckman). This is very accurate compared to a model with approximations.

			2. Number of glass covers, length, width, insulation properties, thickness of the insulation, temperature of fluid inlet and outlet can be varied.

			3. Takes into account the transmission-absorptance product for various angles of incidences.


			Following are the assumptions(as mentioned in the book).

			1. Performance is steady state.

			2. Construction is of parallel sheet and tube type.

			3. The headers cover small area and can be neglected.

			4. The headers provide uniform flow to the collector tubes.

			5. There is no absorption of solar energy by covers insofar as it affects losses from the collector.

			6. Heat flow through the covers is one dimensional.

			7. There is negligible temperature drop through the cover.

			8. The covers are opaque to infra red radiation.

			9. There is one dimensional heat flow from the black insulation.

			10. The sky can be considered a black body for long wavelength radiation at equivalent sky temperature.

			11. The temperature gradients around the tubes can be neglected.

			12. The temperature gradients in the direction of flow and between the tubes can be neglected.

			13. Loss through the front and the back are to the same temperature.

			14. Dust and dirt on the collector are negligible.

			15. Shading of the collector absorber is negligible.

			16. Wind transfer coefficient of assumed to be zero.

	~~Assumptions: Wind transfer coefficient is 0.~~

	*)

			<source lang="a4c">

BademiChetan at 17:55, 8 April 2011

2011-04-08T17:55:49Z

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BademiChetan at 11:53, 7 April 2011

2011-04-07T11:53:18Z

← Older revision		Revision as of 11:53, 7 April 2011
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	University: [http://www.iitm.ac.in Indian Institute of Technology, Madras].		University: [http://www.iitm.ac.in Indian Institute of Technology, Madras].

	~~I've written a simple model of a flat plate solar water heater.~~
	~~I'll put it up when it's appropriate.~~

BademiChetan: Replaced content with 'Name: Chetan Suresh Bademi University: [http://www.iitm.ac.in Indian Institute of Technology, Madras]. I've written a simple model of a flat plate solar water heater. I'll…'

2011-04-07T11:52:33Z

Replaced content with 'Name: Chetan Suresh Bademi University: [http://www.iitm.ac.in Indian Institute of Technology, Madras]. I've written a simple model of a flat plate solar water heater. I'll…'

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BademiChetan at 12:27, 6 April 2011

2011-04-06T12:27:41Z

← Older revision		Revision as of 12:27, 6 April 2011
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	University: [http://www.iitm.ac.in Indian Institute of Technology, Madras].		University: [http://www.iitm.ac.in Indian Institute of Technology, Madras].

	~~I'm applying for [http://ascendwiki.cheme.cmu.edu/Student_projects#Renewable_energy_system_modelling Renewable energy system modelling]~~

	I've written a simple model of a flat plate solar water heater.		I've written a simple model of a flat plate solar water heater.
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	find_heat_loss_coeff_top:		find_heat_loss_coeff_top:
	HeatLossCoeffTop = C / TempPlateMean / N * ( ( TempPlateMean - TempAmbient ) / ( 1.07886 * N + 1) )^E		HeatLossCoeffTop = C / TempPlateMean / N * ( ( TempPlateMean - TempAmbient ) / ( 1.07886 * N + 1) )^E

	+ 5.67E-8 * (TempPlateMean + TempAmbient) (TempPlateMean^2 + TempAmbient^2)/( 1 / EmittancePlate - N + ( 2.07886 N + 0.133 *EmittancePlate ) / EmittanceGlass) ;		+ 5.67E-8 * (TempPlateMean + TempAmbient) (TempPlateMean^2 + TempAmbient^2)/( 1 / EmittancePlate - N + ( 2.07886 N + 0.133 *EmittancePlate ) / EmittanceGlass) ;

BademiChetan at 10:55, 6 April 2011

2011-04-06T10:55:07Z

← Older revision		Revision as of 10:55, 6 April 2011
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	find_heat_loss_coeff_top:		find_heat_loss_coeff_top:
	HeatLossCoeffTop = C / TempPlateMean / N * ( ( TempPlateMean - TempAmbient ) / ( 1.07886 * N + 1) )^E + 5.67E-8 * (TempPlateMean + TempAmbient) (TempPlateMean^2 + TempAmbient^2)/( 1 / EmittancePlate - N + ( 2.07886 N + 0.133 *EmittancePlate ) / EmittanceGlass) ;		HeatLossCoeffTop = C / TempPlateMean / N * ( ( TempPlateMean - TempAmbient ) / ( 1.07886 * N + 1) )^E

			+ 5.67E-8 * (TempPlateMean + TempAmbient) (TempPlateMean^2 + TempAmbient^2)/( 1 / EmittancePlate - N + ( 2.07886 N + 0.133 *EmittancePlate ) / EmittanceGlass) ;

	find_heat_loss_coeff_back:		find_heat_loss_coeff_back:

BademiChetan at 10:50, 6 April 2011

2011-04-06T10:50:54Z

← Older revision		Revision as of 10:50, 6 April 2011
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	NetRadiation = SolarRadiation * TransmittanceNormal * AbsorptanceNormal * AngleModifier ;		NetRadiation = SolarRadiation * TransmittanceNormal * AbsorptanceNormal * AngleModifier ;

	(* Calculate HeatLossCoefficient and TempPlateMean by solving equations 6.4.9 and 6.9.4 (Duffie and Beckman) *)		(* Calculate HeatLossCoefficient and TempPlateMean by solving equations 6.4.9 and 6.9.4 iterativelys(Duffie and Beckman) *)

	find_overall_heat_loss_coeff:		find_overall_heat_loss_coeff:
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	[[Image:IncidenceGraph.png\|thumb\|1100px\|1100px\|Incidence Graph generated by ASCEND for the model of simple flat plate solar water heater]]		[[Image:IncidenceGraph.png\|thumb\|1100px\|1100px\|Incidence Graph generated by ASCEND for the model of simple flat plate solar water heater]]
			[[Image:FlatPlateSolarWaterHeaterValues1.png\|thumb\|1100px\|1100px\|Values obtained after solving the model of simple flat plate solar water heater part I]]
			[[Image:FlatPlateSolarWaterHeaterValues2.png\|thumb\|1100px\|1100px\|Values obtained after solving the model of simple flat plate solar water heater part II]]

BademiChetan at 10:43, 6 April 2011

2011-04-06T10:43:08Z

← Older revision		Revision as of 10:43, 6 April 2011
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	Name: Chetan Suresh Bademi		Name: Chetan Suresh Bademi

	University: [http://iitm.ac.in Indian Institute of Technology, Madras].		University: [http://www.iitm.ac.in Indian Institute of Technology, Madras].

	I'm applying for [http://ascendwiki.cheme.cmu.edu/Student_projects#Renewable_energy_system_modelling Renewable energy system modelling]		I'm applying for [http://ascendwiki.cheme.cmu.edu/Student_projects#Renewable_energy_system_modelling Renewable energy system modelling]

BademiChetan at 10:41, 6 April 2011

2011-04-06T10:41:26Z

← Older revision		Revision as of 10:41, 6 April 2011
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	</source>		</source>

	[[Image:IncidenceGraph.png\|thumb\|1100px\|~~1500px~~\|Incidence Graph generated by ASCEND for the model of simple solar water heater]]		[[Image:IncidenceGraph.png\|thumb\|1100px\|1100px\|Incidence Graph generated by ASCEND for the model of simple flat plate solar water heater]]