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#126 2018-02-19 17:19:35

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 27,185

Re: Indoor farming update

On mars with a limited greenhouse size we will feel like we are doing indoors farming in our rooms....

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#127 2018-07-24 18:01:31

MichaelM
Banned
Registered: 2018-07-24
Posts: 1

Re: Indoor farming update

Antius (or anyone), where did you get the values for CO2?  I put the same values in at the NIST website and am getting a Cp of 761 J/kgK and Pr # of 0.78.
--------------------------------------------------------------------------------------------------------------------------------

I did a few heat transfer calculations to help answer this question.

I will calculate convective heat loss from a cylinder approximately at 30cm wide, 2m tall with a temperature of 36C in the Martian atmosphere.   Wind speed = 10mph (4.5m/s).  Density of Martian CO2 at -50°C and 0.81KPa is 0.44mol/m3 or 0.02kg/m3.  Dynamic Viscosity is ~1x10-5pa.s.  On this basis, the Reynolds number is:

Re=ρvL/μ

L is characteristic length, which is equal to 4 times cross-sectional area, divided by perimeter or 0.15m in this case.  Reynolds is therefore 0.02x4.5x0.15/0.00001 = 1350.

Using the cylindrical cross-flow equation, Nusselt number can be calculated:

Nu = 0.193Re^0.618 x Pr^0.33

Prandtl, Pr=Cp.μ/k.

For CO2 under these conditions, k is 0.01W/m.K and Cp at 220K is 1960J/KgK.  So Prandtl is 1.96.  On this basis, Nusselt can be calculated to be 20.8.
The heat transfer coefficient, h= Nu.k/L.  Which works out to be 1.4W/m2K.

For a cyclindrical body with a surface area of ~1m2 and a temperature difference of 86K with the environment, heat loss rate can be calculated using Newton’s Law of Cooling:

Q=hA(T1-T2) = 1.4 x 1 x 86 = 120watts.

By contrast, radiation would lose 400watts of heat from the same body under the same conditions.  So on the Martian surface, heat loss will be dominated by radiation and conduction.  As a rough rule of thumb ‘the convection heat losses in the Martian atmosphere for any structure at room temperature, will be about 30% of the black body radiation heat loss rate’.

In a dust storm, with air velocity of 20m/s, the convective heat transfer coefficient increases roughly 2.5 times and thus reaches 75% of the black body radiation heat loss.

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#128 2018-08-28 19:21:24

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 27,185

Re: Indoor farming update

This is how we combine greenhouse with housing for a colony to get a foothold on mars.

Simular Construction people below ground level with the cieling supporting the plants at a partial pressure while the habitat area could be higher.

BBMdStA.img?h=416&w=799&m=6&q=60&u=t&o=f&l=f

This one shows how a house would possibly look inside but I would leave the above ground structure out of it until further along with colony building.

BBMdNF3.img?h=416&w=799&m=6&q=60&u=t&o=f&l=f

Of course the greenhouse door would have an airlock..

BBMdXtk.img?h=416&w=799&m=6&q=60&u=t&o=f&l=f&x=756&y=695

Possible harvest
BBMdEOw.img?h=416&w=799&m=6&q=60&u=t&o=f&l=f


We can dream or we can plan for what might be....

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#129 2018-08-29 06:36:46

elderflower
Member
Registered: 2016-06-19
Posts: 1,262

Re: Indoor farming update

Why have they put the solar panels inside? Clear glazing will still absorb some incoming radiation and reflect some more, reducing the incident radiation on the panels.

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#130 2018-08-29 13:43:04

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,389
Website

Re: Indoor farming update

elderflower wrote:

Why have they put the solar panels inside? Clear glazing will still absorb some incoming radiation and reflect some more, reducing the incident radiation on the panels.

Very true. But no hail or snow. The high angle implies high latitude. At the equator you would pitch solar panels completely flat, 0° for maximum sunlight. At the pole you would pitch 90°, completely vertical to match latitude; base would have to rotate once per day to track the Sun. At high latitude you could cheat, produce more power in winter, less in summer. Set maximum to half-way between spring/autumnal equinox and winter solstice: latitude plus Earth's axial tilt / 2 = latitude + (23.4392811° / 2). These solar panels have a steep angle implying high latitude, so it should get snow in winter. Inside means no snow on solar panels, but you still need to brush snow off the dome.

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#131 2018-08-29 17:02:31

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 27,185

Re: Indoor farming update

Looking closely at the upper right corner of the panels I can see that these are solar thermal hot water panels to which they are more protected by thermal cycle of freezing in the winter and might not need a heat exchanger as it would be water and not an antifreeze food grade in them.

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#132 2018-10-11 11:25:18

tahanson43206
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Registered: 2018-04-27
Posts: 12,757

Re: Indoor farming update

Given the topic of Indoor farming ...

As an unexpected reward for investigating various farm related topics on Google, I now receive a steady flow of farm related email advertising. Today's incoming included an item which seems (to me at least) to be potentially adaptable for Mars as either a sand shelter, or perhaps even a growing space, as shown on the company web site.  In any case, I wrote the company inviting them to register in the forum for the purpose of collecting advice on how to adapt to Mars.

Begin Quotation:
Fabra Dome is a pioneer and a leader in the hoop barn industry. Fabra Dome is one of the oldest hoop barn providers in the United States.
End Quotation.
www.fabradome.com
(th)

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#133 2018-10-11 17:41:43

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Indoor farming update

They look like big versions of what we call "polytunnels" in the UK. 

The issue on Mars  is pressurisation  - which means the whole structure has to be able to withstand the pressure differential between inside (maybe not full Earth atmospheric pressure, but something close) and the outside which is 0.6% of Earth's atmospheric pressure .

tahanson43206 wrote:

Given the topic of Indoor farming ...

As an unexpected reward for investigating various farm related topics on Google, I now receive a steady flow of farm related email advertising. Today's incoming included an item which seems (to me at least) to be potentially adaptable for Mars as either a sand shelter, or perhaps even a growing space, as shown on the company web site.  In any case, I wrote the company inviting them to register in the forum for the purpose of collecting advice on how to adapt to Mars.

Begin Quotation:
Fabra Dome is a pioneer and a leader in the hoop barn industry. Fabra Dome is one of the oldest hoop barn providers in the United States.
End Quotation.
www.fabradome.com
(th)

Last edited by louis (2018-10-11 17:42:05)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#134 2018-10-11 17:57:47

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 27,185

Re: Indoor farming update

There are a number of shelter builders in the US that make simular product out of a variety of materials for just as many different uses.

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#135 2019-07-31 17:15:01

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 27,185

Re: Indoor farming update

Microbial manufacturing: Genetic engineering breakthrough for urban farming

vertical-farm-oled-lighting-hg.jpg

They were exploring ways on microbial fermentation which create fertilizers, nutrients and non-synthetic pesticides for urban farms, in the form of small molecules.

http://distap.mit.edu/

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#136 2020-09-26 05:28:56

tahanson43206
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Registered: 2018-04-27
Posts: 12,757

Re: Indoor farming update

Here is an article about a gent in Hong Kong who is using shipping containers to grow crops.  This model seems well suited for Mars.  The dimensions are familiar to humans, and a complete package could be shipped to Mars in a collapsed form and reconstructed there.

https://www.yahoo.com/news/ap-photos-fo … 14267.html

(th)

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#137 2020-09-26 06:45:18

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 12,757

Re: Indoor farming update

Here is an article about "regenerative farming"  .... crop rotation is a concept known to humans for thousands of years.

It appears that with development of the scientific method, agricultural practice may have refined the concept.  While the article at the link below is about outdoor farming on Earth, it should be adaptable to the indoor farming environment of Mars.

https://www.yahoo.com/huffpost/climate- … 00193.html


Over the past four years, Gentry has transformed two acres of trash-strewn dirt on Long Island’s southeast coast into a profitable organic farm by betting big on soil. Instead of pumping her crops with pesticides and petrochemical fertilizer, Gentry grows vetch, a hardy pea-like plant, and rye to cover the exposed soil between the rows of greens intended for harvest. She layers the soil with specially mined rock dust that replenishes minerals and pulls carbon from the air. And in the spring and summer, she uses a system of crop rotation ― shifting around where different crops are planted ― so that one plant’s nutrient needs don’t drain the soil. These practices are collectively known as regenerative farming.

(th)

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#138 2021-01-28 07:31:03

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 12,757

Re: Indoor farming update

Here is another update to Louis' topic here ... on Mars, for the forseeable future, ** all ** farming will be indoor ...

Here is an ambitious effort on Earth that may provide insight into what is needed to reliably feed a population on Mars:

https://www.yahoo.com/news/massive-sust … 05253.html

Massive sustainable eco-farm harvests first crop
Thu, January 28, 2021 5:00 AM
This is a massive indoor eco-farm, and it has just harvested its first crop. These beefsteak tomatoes are chemical pesticide-free, non-GMO and grown with 100% rainwater. The 60-acre facility in Morehead, Kentucky is among the largest climate-controlled indoor farms in the U.S. Behind it is ag-tech startup AppHarvest and CEO Jonathan Webb. "It’s a totally different way of looking at agriculture.

(th)

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#139 2021-06-19 09:04:33

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 4,796

Re: Indoor farming update

Orchids in orbit: Seeds tested in space

https://www.spacedaily.com/reports/Orch … e_999.html

Almost 30 grams of Nanjing orchid seeds were carried into space for breeding tests, accompanying three Chinese astronauts in China's Shenzhou XII manned spaceship, which was launched on Thursday. The seeds will be in space for three months.

A red orchid variety, Hongcao, features red buds and seedlings, a popular variant from Nanjing county of Fujian province.

It was selected and bred by the provincial testing center for forestry science and technology, which is affiliated with the Fujian Bureau of Forestry.

Since 2016, the center has been working with the flower research institute of the Academy of Agricultural Sciences of Yunnan province to carry out research on the breeding of Nanjing orchids in space.

About 100 grams of seeds were carried with the Tiangong II manned spacecraft via a Long March 5B large rocket and the Shenzhou XII, resulting in two sterile germinated strains.

Space breeding has been widely applied to innovations in the agricultural industry. Because of its higher probability of genetic variation, this method can cultivate new varieties of orchids with longer bloom cycles and better appearance and fragrance over ordinary ones.

For the experiment, researchers take advantage of the unique conditions of space, including cosmic radiation, the vacuum and microgravity to change the seeds' chromosome structure for laboratory tissue cultivation. Eventually the process generates new varieties.

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#140 2022-01-17 19:26:22

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 27,185

Re: Indoor farming update

bump

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#141 2022-03-18 07:45:38

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 4,796

Re: Indoor farming update

Renovated warehouse earmarked for large-scale vertical farm project
https://www.eadt.co.uk/news/business/on … et-8757704

Indoor vertical farm expanding to Muncie
https://www.wishtv.com/news/inside-indi … to-muncie/

A New Jersey start-up is using vertical farming to start selling fruit.

https://www.cnbc.com/2022/03/15/bowerys … york-.html?

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#142 2022-04-13 04:31:12

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 4,796

Re: Indoor farming update

Global Vertical Farming Market to Reach $5.8 Billion by 2026
https://finance.yahoo.com/news/global-v … 00644.html

Retro scifi is back?

Futuristic ‘automat’ dining thrived a century ago. Can covid revive it?
https://wapo.st/3jpzfUJ

Fungi could be used make soil from asteroids, as well as provide the structural backbone for homes built on Mars.
https://astronomy.com/news/2022/04/fung … es-on-mars

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#143 2022-07-12 06:32:36

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 4,796

Re: Indoor farming update

In Sri Lanka, Organic Farming Went Catastrophically Wrong
https://news.slashdot.org/story/22/07/1 … ally-wrong

Faced with a deepening economic and humanitarian crisis, Sri Lanka called off an ill-conceived national experiment in organic agriculture this winter. From a report in March:
Sri Lankan President Gotabaya Rajapaksa promised in his 2019 election campaign to transition the country's farmers to organic agriculture over a period of 10 years. Last April, Rajapaksa's government made good on that promise, imposing a nationwide ban on the importation and use of synthetic fertilizers and pesticides and ordering the country's 2 million farmers to go organic.

The result was brutal and swift. Against claims that organic methods can produce comparable yields to conventional farming, domestic rice production fell 20 percent in just the first six months. Sri Lanka, long self-sufficient in rice production, has been forced to import $450 million worth of rice even as domestic prices for this staple of the national diet surged by around 50 percent. The ban also devastated the nation's tea crop, its primary export and source of foreign exchange.

By November 2021, with tea production falling, the government partially lifted its fertilizer ban on key export crops, including tea, rubber, and coconut. Faced with angry protests, soaring inflation, and the collapse of Sri Lanka's currency, the government finally suspended the policy for several key crops -- including tea, rubber, and coconut -- last month, although it continues for some others. The government is also offering $200 million to farmers as direct compensation and an additional $149 million in price subsidies to rice farmers who incurred losses. That hardly made up for the damage and suffering the ban produced. Farmers have widely criticized the payments for being massively insufficient and excluding many farmers, most notably tea producers, who offer one of the main sources of employment in rural Sri Lanka. The drop in tea production alone is estimated to result in economic losses of $425 million.

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#144 2022-07-12 06:47:27

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 12,757

Re: Indoor farming update

This is an opportunity for thoughtful analysis of a leadership failure.

This is NOT a time for the kind of thoughtless emotional rants that so often show up in the NewMars forum.

It seems to me that the Mars enterprise requires a cooperative undertaking to build a viable, sustainable agriculture that does NOT depend upon imports.

It is not clear (to me for sure) why the Sri Lanka experiment failed, but it would seem there was a significant mismatch between the plan and the performance.

The education level of the work force has to have been a factor in the failure.

The communications required would seem to have been missing, but that is a detail I hope to see revealed in a thoughtful analysis.

(th)

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#145 2023-01-21 20:21:07

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 27,185

Re: Indoor farming update

Who knew we were already thinking of a water poor condition that we will see for a time on Mars. These indoor farms can grow crops with 90% less water — and they’re transforming how we think about local produce

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